[]A TREATISE OF Human Nature.

SECT. I. Of the Origin of our Ideas.

ALL the perceptions of the human mind reſolve themſelves into two diſtinct kinds, which I ſhall call IMPRESSIONS and IDEAS. The difference betwixt theſe conſiſts in the degrees of force and livelineſs, with which [12] they ſtrike upon the mind, and make their way into our thought or conſciouſneſs. Thoſe perceptions, which enter with moſt force and violence, we may name impreſſions; and under this name I comprehend all our ſenſa⯑tions, paſſions and emotions, as they make their firſt appearance in the ſoul. By ideas I mean the faint images of theſe in thinking and reaſoning; ſuch as, for inſtance, are all the perceptions excited by the preſent diſ⯑courſe, excepting only, thoſe which ariſe from the ſight and touch, and excepting the immediate pleaſure or uneaſineſs it may oc⯑caſion. I believe it will not be very neceſ⯑ſary to employ many words in explaining this diſtinction. Every one of himſelf will rea⯑dily perceive the difference betwixt feeling and thinking. The common degrees of theſe are eaſily diſtinguiſhed; tho' it is not impoſ⯑ſible but in particular inſtances they may very nearly approach to each other. Thus in ſleep, in a fever, in madneſs, or in any very violent emotions of ſoul, our ideas may ap⯑proach to our impreſſions: As on the other hand it ſometimes happens, that the impreſ⯑ſions are ſo faint and low, that we cannot diſtinguiſh them from our ideas. But not⯑withſtanding this near reſemblance in a few inſtances, they are in general ſo very different, [13] that no-one can make a ſcruple to rank them under diſtinct heads, and aſſign to each a peculiar name to mark the difference ^*.

THERE is another diviſion of our percep⯑tions, which it will be convenient to obſerve, and which extends itſelf both to our impreſ⯑ſions and ideas. This diviſion is into SIMPLE and COMPLEX. Simple perceptions or im⯑preſſions and ideas are ſuch as admit of no diſtinction nor ſeparation. The complex are the contrary to theſe, and may be diſtin⯑guiſhed into parts. Tho' a particular colour, taſte, and ſmell are qualities all united toge⯑ther in this apple, 'tis eaſy to perceive they are not the ſame, but are at leaſt diſtinguiſh⯑able from each other.

HAVING by theſe diviſions given an order and arrangement to our objects, we may now apply ourſelves to conſider with the more accuracy their qualities and relations. The firſt circumſtance, that ſtrikes my eye, is the great reſemblance betwixt our impreſſions [14] and ideas in every other particular, except their degree of force and vivacity. The one ſeem to be in a manner the reflexion of the other; ſo that all the perceptions of the mind are double, and appear both as impreſ⯑ſions and ideas. When I ſhut my eyes and think of my chamber, the ideas I form are exact repreſentations of the impreſſions I felt; nor is there any circumſtance of the one, which is not to be found in the other. In running over my other perceptions, I find ſtill the ſame reſemblance and repreſentation. Ideas and impreſſions appear always to cor⯑reſpond to each other. This circumſtance ſeems to me remarkable, and engages my attention for a moment.

UPON a more accurate ſurvey I find I have been carried away too far by the firſt appearance, and that I muſt make uſe of the diſtinction of perceptions into ſimple and complex, to limit this general deciſion, that all our ideas and impreſſions are reſembling. I obſerve, that many of our complex ideas never had impreſſions, that correſponded to them, and that many of our complex im⯑preſſions never are exactly copied in ideas. I can imagine to myſelf ſuch a city as the New Jeruſalem, whoſe pavement is gold and walls are rubies, tho' I never ſaw any ſuch. [15] I have ſeen Paris; but ſhall I affirm I can form ſuch an idea of that city, as will per⯑fectly repreſent all its ſtreets and houſes in their real and juſt proportions?

I PERCEIVE, therefore, that tho' there is in general a great reſemblance betwixt our complex impreſſions and ideas, yet the rule is not univerſally true, that they are exact co⯑pies of each other. We may next conſider how the caſe ſtands with our ſimple percep⯑tions. After the moſt accurate examination, of which I am capable, I venture to affirm, that the rule here holds without any excep⯑tion, and that every ſimple idea has a ſimple impreſſion, which reſembles it; and every ſimple impreſſion a correſpondent idea. That idea of red, which we form in the dark, and that impreſſion, which ſtrikes our eyes in ſun-ſhine, differ only in degree, not in na⯑ture. That the caſe is the ſame with all our ſimple impreſſions and ideas, 'tis impoſſi⯑ble to prove by a particular enumeration of them. Every one may ſatisfy himſelf in this point by running over as many as he pleaſes. But if any one ſhould deny this univerſal re⯑ſemblance, I know no way of convincing him, but by deſiring him to ſhew a ſimple impreſ⯑ſion, that has not a correſpondent idea, or a ſimple idea, that has not a correſpondent im⯑preſſion. [16] If he does not anſwer this chal⯑lenge, as 'tis certain he cannot, we may from his ſilence and our own obſervation eſtabliſh our concluſion.

THUS we find, that all ſimple ideas and impreſſions reſemble each other; and as the complex are formed from them, we may affirm in general, that theſe two ſpecies of perception are exactly correſpondent. Having diſcover'd this relation, which requires no farther examination, I am curious to find ſome other of their qualities. Let us con⯑ſider how they ſtand with regard to their exiſtence, and which of the impreſſions and ideas are cauſes, and which effects.

THE full examination of this queſtion is the ſubject of the preſent treatiſe; and there⯑fore we ſhall here content ourſelves with eſtabliſhing one general propoſition, That all our ſimple ideas in their firſt appearance are deriv'd from ſimple impreſſions, which are cor⯑reſpondent to them, and which they exactly repreſent.

IN ſeeking for phaenomena to prove this propoſition, I find only thoſe of two kinds; but in each kind the phaenomena are obvious, numerous, and concluſive. I firſt make my⯑ſelf certain, by a new review, of what I have already aſſerted, that every ſimple impreſſion [17] is attended with a correſpondent idea, and every ſimple idea with a correſpondent im⯑preſſion. From this conſtant conjunction of reſembling perceptions I immediately con⯑clude, that there is a great connexion be⯑twixt our correſpondent impreſſions and ideas, and that the exiſtence of the one has a con⯑ſiderable influence upon that of the other. Such a conſtant conjunction, in ſuch an in⯑finite number of inſtances, can never ariſe from chance; but clearly proves a dependence of the impreſſions on the ideas, or of the ideas on the impreſſions. That I may know on which ſide this dependence lies, I conſi⯑der the order of their firſt appearance; and find by conſtant experience, that the ſimple impreſſions always take the precedence of their correſpondent ideas, but never appear in the contrary order. To give a child an idea of ſcarlet or orange, of ſweet or bitter, I preſent the objects, or in other words, con⯑vey to him theſe impreſſions; but proceed not ſo abſurdly, as to endeavour to produce the impreſſions by exciting the ideas. Our ideas upon their appearance produce not their correſpondent impreſſions, nor do we per⯑ceive any colour, or feel any ſenſation merely upon thinking of them. On the other hand we find, that any impreſſions either of the [18] mind or body is conſtantly followed by an idea, which reſembles it, and and is only different in the degrees of force and livelineſs. The conſtant conjunction of our reſembling perceptions, is a convincing proof, that the one are the cauſes of the other; and this prio⯑rity of the impreſſions is an equal proof, that our impreſſions are the cauſes of our ideas, not our ideas of our impreſſions.

TO confirm this I conſider another plain and convincing phaenomenon; which is, that where-ever by any accident the faculties, which give riſe to any impreſſions, are ob⯑ſtructed in their operations, as when one is born blind or deaf; not only the impreſſions are loſt, but alſo their correſpondent ideas; ſo that there never appear in the mind the leaſt traces of either of them. Nor is this only true, where the organs of ſenſation are entirely deſtroy'd, but likewiſe where they have never been put in action to produce a particular impreſſion. We cannot form to ourſelves a juſt idea of the taſte of a pine⯑apple, without having actually taſted it.

THERE is however one contradictory phaenomenon, which may prove, that 'tis not abſolutely impoſſible for ideas to go before their correſpondent impreſſions. I believe it will readily be allow'd, that the ſe⯑veral [19] diſtinct ideas of colours, which enter by the eyes, or thoſe of ſounds, which are convey'd by the hearing, are really different from each other, tho' at the ſame time re⯑ſembling. Now if this be true of different colours, it muſt be no leſs ſo of the different ſhades of the ſame colour, that each of them produces a diſtinct idea, independent of the reſt. For if this ſhou'd be deny'd, 'tis poſ⯑ſible, by the continual gradation of ſhades, to run a colour inſenſibly into what is moſt remote from it; and if you will not allow any of the means to be different, you cannot without abſurdity deny the extremes to be the ſame. Suppoſe therefore a perſon to have enjoyed his ſight for thirty years, and to have become perfectly well acquainted with colours of all kinds, excepting one particular ſhade of blue, for inſtance, which it never has been his fortune to meet with. Let all the different ſhades of that colour, except that ſingle one, be plac'd before him, de⯑ſcending gradually from the deepeſt to the lighteſt; 'tis plain, that he will perceive a blank, where that ſhade is wanting, and will be ſenſible, that there is a greater di⯑ſtance in that place betwixt the contiguous colours, than in any other. Now I aſk, whe⯑ther 'tis poſſible for him, from his own ima⯑gination, [20] to ſupply this deficiency, and raiſe up to himſelf the idea of that particular ſhade, tho' it had never been conveyed to him by his ſenſes? I believe there are few but will be of opinion that he can; and this may ſerve as a proof, that the ſimple ideas are not always derived from the cor⯑reſpondent impreſſions; tho' the inſtance is ſo particular and ſingular, that 'tis ſcarce worth our obſerving, and does not merit that for it alone we ſhould alter our general maxim.

BUT beſides this exception, it may not be amiſs to remark on this head, that the principle of the priority of impreſſions to ideas muſt be underſtood with another limita⯑tion, viz. that as our ideas are images of our impreſſions, ſo we can form ſecondary ideas, which are images of the primary; as appears from this very reaſoning concerning them. This is not, properly ſpeaking, an exception to the rule ſo much as an explanation of it. Ideas produce the images of themſelves in new ideas; but as the firſt ideas are ſuppoſed to be derived from impreſſions, it ſtill remains true, that all our ſimple ideas proceed either mediately or immediately, from their correſpondent impreſſions.

[21] THIS then is the firſt principle I eſtabliſh in the ſcience of human nature; nor ought we to deſpiſe it becauſe of the ſimplicity of its appearance. For 'tis remarkable, that the preſent queſtion concerning the precedency of our impreſſions or ideas, is the ſame with what has made ſo much noiſe in other terms, when it has been diſputed whether there be any innate ideas, or whether all ideas be de⯑rived from ſenſation and reflexion. We may obſerve, that in order to prove the ideas of extenſion and colour not to be innate, philo⯑ſophers do nothing but ſhew, that they are conveyed by our ſenſes. To prove the ideas of paſſion and deſire not to be innate, they obſerve that we have a preceding experience of theſe emotions in ourſelves. Now if we carefully examine theſe arguments, we ſhall find that they prove nothing but that ideas are preceded by other more lively perceptions, from which they are derived, and which they repreſent. I hope this clear ſtating of the queſtion will remove all diſputes concerning it, and will render this principle of more uſe in our reaſonings, than it ſeems hitherto to have been.

SECT. II. Diviſion of the ſubject.

SINCE it appears, that our ſimple im⯑preſſions are prior to their correſpon⯑dent ideas, and that the exceptions are very rare, method ſeems to require we ſhould examine our impreſſions, before we conſider our ideas. Impreſſions may be divided into two kinds, thoſe of SENSATION and thoſe of REFLEXION. The firſt kind ariſes in the ſoul originally, from unknown cauſes. The ſecond is derived in a great meaſure from our ideas, and that in the following order. An impreſſion firſt ſtrikes upon the ſenſes, and makes us perceive heat or cold, thirſt or hunger, pleaſure or pain of ſome kind or other. Of this impreſſion there is a copy taken by the mind, which remains after the impreſſion ceaſes; and this we call an idea. This idea of pleaſure or pain, when it returns upon the ſoul, produces the new impreſſions of deſire and averſion, hope and fear, which may properly be called impreſſions of refle⯑xion, becauſe derived from it. Theſe again are copied by the memory and imagination, and become ideas; which perhaps in their turn give riſe to other impreſſions and ideas. [23] So that the impreſſions of reflexion are only antecedent to their correſpondent ideas; but poſterior to thoſe of ſenſation, and deriv'd from them. The examination of our ſenſa⯑tions belongs more to anatomiſts and natural philoſophers than to moral; and therefore ſhall not at preſent be enter'd upon. And as the impreſſions of reflection, viz. paſſions, deſires, and emotions, which principally de⯑ſerve our attention, ariſe moſtly from ideas, 'twill be neceſſary to reverſe that method, which at firſt ſight ſeems moſt natural; and in order to explain the nature and principles of the human mind, give a particular ac⯑count of ideas, before we proceed to impreſ⯑ſions. For this reaſon I have here choſen to begin with ideas.

SECT. III. Of the ideas of the memory and imagination.

WE find by experience, that when any impreſſion has been preſent with the mind, it again makes its appearance there as an idea; and this it may do after two diffe⯑rent ways: either when in its new appearance it retains a conſiderable degree of its firſt vi⯑vacity, and is ſomewhat intermediate betwixt [24] an impreſſion and an idea; or when it in⯑tirely loſes that vivacity, and is a perfect idea. The faculty, by which we repeat our im⯑preſſions in the firſt manner, is called the MEMORY, and the other the IMAGINA⯑TION. 'Tis evident at firſt ſight, that the ideas of the memory are much more lively and ſtrong than thoſe of the imagination, and that the former faculty paints its objects in more diſtinct colours, than any which are employ'd by the latter. When we re⯑member any paſt event, the idea of it flows in upon the mind in a forcible manner; whereas in the imagination the perception is faint and languid, and cannot without dif⯑ficulty be preſerv'd by the mind ſteddy and uniform for any conſiderable time. Here then is ſenſible difference betwixt one ſpe⯑cies of ideas and another. But of this more fully hereafter ^*.

THERE is another difference betwixt theſe two kinds of ideas, which is no leſs evident, namely that tho' neither the ideas of the me⯑mory nor imagination, neither the lively nor faint ideas can make their appearance in the mind, unleſs their correſpondent impreſſions have gone before to prepare the way for them, yet the imagination is not reſtrain'd to the ſame order and form with the ori⯑ginal [25] impreſſions; while the memory is in a manner ty'd down in that reſpect, with⯑out any power of variation.

'TIS evident, that the memory preſerves the original form, in which its objects were preſented, and that where-ever we depart from it in recollecting any thing, it proceeds from ſome defect or imperfection in that fa⯑culty. An hiſtorian may, perhaps, for the more convenient carrying on of his narration, relate an event before another, to which it was in fact poſterior; but then he takes no⯑tice of this diſorder, if he be exact; and by that means replaces the idea in its due poſi⯑tion. 'Tis the ſame caſe in our recollection of thoſe places and perſons, with which we were formerly acquainted. The chief exerciſe of the memory is not to preſerve the ſimple ideas, but their order and poſition. In ſhort, this principle is ſupported by ſuch a number of common and vulgar phaenomena, that we may ſpare ourſelves the trouble of inſiſting on it any farther.

THE ſame evidence follows us in our ſa⯑cond principle, of the liberty of the imagina⯑tion to tranſpoſe and change its ideas. The fables we meet with in poems and romances put this entirely out of queſtion. Nature there is totally confounded, and nothing men⯑tioned [26] but winged horſes, fiery dragons, and monſtrous giants. Nor will this liberty of the fancy appear ſtrange, when we conſider, that all our ideas are copy'd from our impreſ⯑ſions, and that there are not any two impreſ⯑ſions which are perfectly inſeparable. Not to mention, that this is an evident conſe⯑quence of the diviſion of ideas into ſimple and complex. Where-ever the imagination perceives a difference among ideas, it can ea⯑ſily produce a ſeparation.

SECT. IV. Of the connexion or aſſociation of ideas.

AS all ſimple ideas may be ſeparated by the imagination, and may be united again in what form it pleaſes, nothing wou'd be more unaccountable than the operations of that faculty, were it not guided by ſome uni⯑verſal principles, which render it, in ſome meaſure, uniform with itſelf in all times and places. Were ideas entirely looſe and un⯑connected, chance alone wou'd join them; and 'tis impoſſible the ſame ſimple ideas ſhould fall regularly into complex ones (as they com⯑monly do) without ſome bond of union among them, ſome aſſociating quality, by [27] which one idea naturally introduces another. This uniting principle among ideas is not to be conſider'd as an inſeparable connexion; for that has been already excluded from the imagination: Nor yet are we to conclude, that without it the mind cannot join two ideas; for nothing is more free than that fa⯑culty: but we are only to regard it as a gen⯑tle force, which commonly prevails, and is the cauſe why, among other things, languages ſo nearly correſpond to each other; nature in a manner pointing out to every one thoſe ſimple ideas, which are moſt proper to be united into a complex one. The qualities, from which this aſſociation ariſes, and by which the mind is after this manner con⯑vey'd from one idea to another, are three, viz. RESEMBLANCE, CONTIGUITY in time or place, and CAUSE and EFFECT.

I BELIEVE it will not be very neceſſary to prove, that theſe qualities produce an aſ⯑ſociation among ideas, and upon the appear⯑ance of one idea naturally introduce another. 'Tis plain, that in the courſe of our think⯑ing, and in the conſtant revolution of our ideas, our imagination runs eaſily from one idea to any other that reſembles it, and that this quality alone is to the fancy a ſufficient bond and aſſociation. 'Tis likewiſe evident, [28] that as the ſenſes, in changing their objects, are neceſſitated to change them regularly, and take them as they lie contiguous to each other, the imagination muſt by long cuſtom acquire the ſame method of thinking, and run along the parts of ſpace and time in con⯑ceiving its objects. As to the connexion, that is made by the relation of cauſe and effect, we ſhall have occaſion afterwards to examine it to the bottom, and therefore ſhall not at preſent inſiſt upon it. 'Tis ſufficient to obſerve, that there is no relation, which produces a ſtronger connexion in the fancy, and makes one idea more readily recall an⯑other, than the relation of cauſe and effect betwixt their objects.

THAT we may underſtand the full ex⯑tent of theſe relations, we muſt conſider, that two objects are connected together in the imagination, not only when the one is immediately reſembling, contiguous to, or the cauſe of the other, but alſo when there is interpoſed betwixt them a third object, which bears to both of them any of theſe relations. This may be carried on to a great length; tho' at the ſame time we may ob⯑ſerve, that each remove conſiderably weakens the relation. Couſins in the fourth degree are connected by cauſation, if I may be allowed [29] to uſe that term; but not ſo cloſely as bro⯑thers, much leſs as child and parent. In general we may obſerve, that all the rela⯑tions of blood depend upon cauſe and effect, and are eſteemed near or remote, according to the number of connecting cauſes interpos'd betwixt the perſons.

OF the three relations above-mention'd this of cauſation is the moſt extenſive. Two objects may be conſider'd as plac'd in this re⯑lation, as well when one is the cauſe of any of the actions or motions of the other, as when the former is the cauſe of the exiſtence of the latter. For as that action or motion is nothing but the object itſelf, conſider'd in a certain light, and as the object continues the ſame in all its different ſituations, 'tis eaſy to imagine how ſuch an influence of objects upon one another may connect them in the imagination.

WE may carry this farther, and remark, not only that two objects are connected by the relation of cauſe and effect, when the one produces a motion or any action in the other, but alſo when it has a power of pro⯑ducing it. And this we may obſerve to be the ſource of all the relations of intereſt and duty, by which men influence each other in ſociety, and are plac'd in the ties of govern⯑ment [30] and ſubordination. A maſter is ſuch-a⯑one as by his ſituation, ariſing either from force or agreement, has a power of directing in cer⯑tain particulars the actions of another, whom we call ſervant. A judge is one, who in all diſputed caſes can fix by his opinion the poſ⯑ſeſſion or property of any thing betwixt any members of the ſociety. When a perſon is poſſeſs'd of any power, there is no more re⯑quired to convert it into action, but the ex⯑ertion of the will; and that in every caſe is conſider'd as poſſible, and in many as proba⯑ble; eſpecially in the caſe of authority, where the obedience of the ſubject is a pleaſure and advantage to the ſuperior.

THESE are therefore the principles of union or coheſion among our ſimple ideas, and in the imagination ſupply the place of that inſeparable connexion, by which they are united in our memory. Here is a kind of ATTRACTION, which in the mental world will be found to have as extraordinary effects as in the natural, and to ſhew itſelf in as ma⯑ny and as various forms. Its effects are every where conſpicuous; but as to its cauſes, they are moſtly unknown, and muſt be reſolv'd into original qualities of human nature, which I pretend not to explain. Nothing is more requiſite for a true philoſopher, than to re⯑ſtrain [31] the intemperate deſire of ſearching in⯑to cauſes, and having eſtabliſh'd any doctrine upon a ſufficient number of experiments, reſt contented with that, when he ſees a farther examination would lead him into obſcure and uncertain ſpeculations. In that caſe his enqui⯑ry wou'd be much better employ'd in exa⯑mining the effects than the cauſes of his prin⯑ciple.

AMONGST the effects of this union or aſ⯑ſociation of ideas, there are none more re⯑markable, than thoſe complex ideas, which are the common ſubjects of our thoughts and reaſoning, and generally ariſe from ſome prin⯑ciple of union among our ſimple ideas. Theſe complex ideas may be divided into Relations, Modes, and Subſtances. We ſhall briefly examine each of theſe in order, and ſhall ſubjoin ſome conſiderations concerning our general and par⯑ticular ideas, before we leave the preſent ſub⯑ject, which may be conſider'd as the elements of this philoſophy.

SECT. V. Of relations.

THE word RELATION is commonly uſed in two ſenſes conſiderably diffe⯑rent from each other. Either for that quali⯑ty, by which two ideas are connected toge⯑ther in the imagination, and the one naturally introduces the other, after the manner above⯑explained; or for that particular circum⯑ſtance, in which, even upon the arbitrary union of two ideas in the fancy, we may think proper to compare them. In common language the former is always the ſenſe, in which we uſe the word, relation; and 'tis only in philoſophy, that we extend it to mean any particular ſubject of compariſon, without a connecting principle. Thus diſtance will be allowed by philoſophers to be a true relation, becauſe we acquire an idea of it by the comparing of objects: But in a common way we ſay, that nothing can be more diſtant than ſuch or ſuch things from each other, no⯑thing can have leſs relation; as if diſtance and relation were incompatible.

IT may perhaps be eſteemed an endleſs taſk to enumerate all thoſe qualities, which [33] make objects admit of compariſon, and by which the ideas of philoſophical relation are produced. But if we diligently conſider them, we ſhall find that without difficulty they may be compriz'd under ſeven general heads, which may be conſidered as the ſources of all philoſophical relation.

1. THE firſt is reſemblance: And this is a relation, without which no philoſophical relation can exiſt; ſince no objects will ad⯑mit of compariſon, but what have ſome de⯑gree of reſemblance. But tho' reſemblance be neceſſary to all philoſophical relation, it does not follow, that it always produces a connexion or aſſociation of ideas. When a quality becomes very general, and is common to a great many individuals, it leads not the mind directly to any one of them; but by preſenting at once too great a choice, does thereby prevent the imagination from fixing on any ſingle object.

2. Identity may be eſteem'd a ſecond ſpe⯑cies of relation. This relation I here conſi⯑der as apply'd in its ſtricteſt ſenſe to conſtant and unchangeable objects; without examin⯑ing the nature and foundation of perſonal identity, which ſhall find its place afterwards. Of all relations the moſt univerſal is that of [34] identity, being common to every being, whoſe exiſtence has any duration.

3. AFTER identity the moſt univerſal and comprehenſive relations are thoſe of Space and Time, which are the ſources of an infi⯑nite number of compariſons, ſuch as diſtant, contiguous, above, below, before, after, &c.

4. ALL thoſe objects, which admit of quantity, or number, may be compar'd in that particular; which is another very fertile ſource of relation.

5. WHEN any two objects poſſeſs the ſame quality in common, the degrees, in which they poſſeſs it, form a fifth ſpecies of relation. Thus of two objects, which are both heavy, the one may be either of greater, or leſs weight than with the other. Two colours, that are of the ſame kind, may yet be of different ſhades, and in that re⯑ſpect admit of compariſon.

6. THE relation of contrariety may at firſt ſight be regarded as an exception to the rule, that no relation of any kind can ſub⯑ſiſt without ſome degree of reſemblance. But let us conſider, that no two ideas are in themſelves contrary, except thoſe of exiſtence and non-exiſtence, which are plainly reſem⯑bling, as implying both of them an idea of the object; tho' the latter excludes the ob⯑ject [35] from all times and places, in which it is ſuppoſed not to exiſt.

7. ALL other objects, ſuch as fire and water, heat, and cold, are only found to be contrary from experience, and from the con⯑trariety of their cauſes or effects; which re⯑lation of cauſe and effect is a ſeventh philoſo⯑phical relation, as well as a natural one. The reſemblance implied in this relation, ſhall be explain'd afterwards.

IT might naturally be expected, that I ſhould join difference to the other relations. But that I conſider rather as a negation of relation, than as any thing real or poſitive. Difference is of two kinds as oppos'd either to identity or reſemblance. The firſt is call'd a difference of number; the other of kind.

SECT. VI. Of modes and ſubſtances.

I WOU'D fain aſk thoſe philoſophers, who found ſo much of their reaſonings on the diſtinction of ſubſtance and accident, and imagine we have clear ideas of each, whether the idea of ſubſtance be deriv'd from the impreſſions of ſenſation of reflection? If it be convey'd to us by our ſenſes, I aſk, which of them; and after what manner? [34] [...] [35] [...] [36] If it be perceiv'd by the eyes, it muſt be a colour; if by the ears, a ſound; if by the pa⯑late, a taſte; and ſo of the other ſenſes. But I believe none will aſſert, that ſubſtance is either a colour, or ſound, or a taſte. The idea of ſubſtance muſt therefore be deriv'd from an impreſſion of reflection, if it really exiſt. But the impreſſions of reflection re⯑ſlove themſelves into our paſſions and emo⯑tions; none of which can poſſibly repreſent a ſubſtance. We have therefore no idea of ſubſtance, diſtinct from that of a collection of particular qualities, nor have we any other meaning when we either talk or rea⯑ſon concerning it.

THE idea of a ſubſtance as well as that of a mode, is nothing but a collection of ſimple ideas, that are united by the imagination, and have a particular name aſſigned them, by which we are able to recal, either to ourſelves or others, that collection. But the difference betwixt theſe ideas conſiſts in this, that the particular qualities, which form a ſubſtance, are commonly refer'd to an un⯑known ſomething, in which they are ſuppoſed to inher; or granting this fiction ſhould not take place, are at leaſt ſuppoſed to be cloſely and inſeparably connected by the relations of contiguity and cauſation. The effect of [37] this is, that whatever new ſimple quality we diſcover to have the ſame connexion with the reſt, we immediately comprehend it among them, even tho' it did not enter into the firſt conception of the ſubſtance. Thus our idea of gold may at firſt be a yellow colour, weight, malleableneſs, fuſibility; but upon the diſcovery of its diſſolubility in aqua regia, we join that to the other qualities, and ſup⯑poſe it to belong to the ſubſtance as much as if its idea had from the beginning made a part of the compound one. The principle of union being regarded as the chief part of the complex idea, gives entrance to whatever quality afterwards occurs, and is equally com⯑prehended by it, as are the others, which firſt preſented themſelves.

THAT this cannot take place in modes, is evident from conſidering their nature. The ſimple ideas of which modes are formed, ei⯑ther repreſent qualities, which are not uni⯑ted by contiguity and cauſation, but are diſ⯑pers'd in different ſubjects; or if they be all united together, the uniting principle is not regarded as the foundation of the complex idea. The idea of a dance is an inſtance of the firſt kind of modes; that of beauty of the ſecond. The reaſon is obvious, why ſuch complex ideas cannot receive any new [38] idea, without changing the name, which diſtinguiſhes the mode.

SECT. VII. Of abſtract ideas.

A VERY material queſtion has been ſtarted concerning abſtract or general ideas, whether they be general or particular in the mind's conception of them. A ^* great philoſopher has diſputed the receiv'd opinion in this particular, and has aſſerted, that all general ideas are nothing but particular ones, annexed to a certain term, which gives them a more extenſive ſignification, and makes them recal upon occaſion other individuals, which are ſimilar to them. As I look upon this to be one of the greateſt and moſt va⯑luable diſcoveries that has been made of late years in the republic of letters, I ſhall here endeavour to confirm it by ſome arguments, which I hope will put it beyond all doubt and controverſy.

'TIS EVIDENT, that in forming moſt of our general ideas, if not all of them, we abſtract from every particular degree of quantity and quality, and that an object ceaſes not to be of any particular ſpecies on [39] account of every ſmall alteration in its ex⯑tenſion, duration and other properties. It may therefore be thought, that here is a plain dilemma, that decides concerning the na⯑ture of thoſe abſtract ideas, which have af⯑forded ſo much ſpeculation to philoſophers. The abſtract idea of a man repreſents men of all ſizes and all qualities; which 'tis con⯑cluded it cannot do, but either by repre⯑ſenting at once all poſſible ſizes and all poſ⯑ſible qualities, or by repreſenting no parti⯑cular one at all. Now it having been e⯑ſteemed abſurd to defend the former pro⯑poſition, as implying an infinite capacity in the mind, it has been commonly infer'd in favour of the latter; and our abſtract ideas have been ſuppos'd to repreſent no particular degree either of quantity or quality. But that this inference is erroneous. I ſhall en⯑deavour to make appear, firſt, by proving, that 'tis utterly impoſſible to conceive any quantity or quality, without forming a pre⯑ciſe notion of its degrees: And ſecondly by ſhowing, that tho' the capacity of the mind be not infinite, yet we can at once form a notion of all poſſible degrees of quantity and quality, in ſuch a manner at leaſt, as, how⯑ever imperfect, may ſerve all the purpoſes of reflection and converſation.

[40] To begin with the firſt propoſition, that the mind cannot form any notion of quantity or quality without forming a preciſe notion of degrees of each; we may prove this by the three following arguments. Firſt, We have obſerv'd, that whatever objects are different are diſtinguiſhable, and that whatever ob⯑jects are diſtinguiſhable are ſeparable by the thought and imagination. And we may here add, that theſe propoſitions are equally true in the inverſe, and that whatever ob⯑jects are ſeparable are alſo diſtinguiſhable, and that whatever objects are diſtinguiſh⯑able are alſo different. For how is it poſſible we can ſeparate what is not diſtinguiſhable, or diſtinguiſh what is not different? In or⯑der therefore to know, whether abſtraction implies a ſeparation, we need only conſider it in this view, and examine, whether all the circumſtances, which we abſtract from in our general ideas, be ſuch as are diſtin⯑guiſhable and different from thoſe, which we retain as eſſential parts of them. But 'tis evident at firſt ſight, that the preciſe length of a line is not different nor diſtinguiſhable from the line itſelf; nor the preciſe degree of any quality from the quality. Theſe ideas, therefore, admit no more of ſeparation than they do of diſtinction and difference. They [41] are conſequently conjoined with each other in the conception; and the general idea of a line, notwithſtanding all our abſtractions and refinements, has in its appearance in the mind a preciſe degree of quantity and qua⯑lity; however it may be made to repreſent others, which have different degrees of both.

SECONDLY, 'tis confeſt, that no object can appear to the ſenſes; or in other words, that no impreſſion can become preſent to the mind, without being determin'd in its de⯑grees both of quantity and quality. The confuſion, in which impreſſions are ſome⯑times involv'd, proceeds only from their faintneſs and unſteadineſs, not from any ca⯑pacity in the mind to receive any impreſſion, which in its real exiſtence has no particular degree nor proportion. That is a contra⯑diction in terms; and even implies the flat⯑teſt of all contradictions, viz. that 'tis poſ⯑ſible for the ſame thing both to be and not to be.

Now ſince all ideas are deriv'd from impreſſions, and are nothing but copies and repreſentations of them, whatever is true of the one muſt be acknowledg'd concerning the other. Impreſſions and ideas differ only in their ſtrength and vivacity. The fore⯑going concluſion is not founded on any par⯑ticular [42] degree of vivacity. It cannot there⯑fore be affected by any variation in that particular. An idea is a weaker impreſ⯑ſion; and as a ſtrong impreſſion muſt ne⯑ceſſarily have a determinate quantity and quality, the caſe muſt be the ſame with its copy or repreſentative.

THIRDLY, 'tis a principle generally re⯑ceiv'd in philoſophy, that every thing in na⯑ture is individual, and that 'tis utterly ab⯑ſurd to ſuppoſe a triangle really exiſtent, which has no preciſe proportion of ſides and angles. If this therefore be abſurd in fact and reality, it muſt alſo be abſurd in idea; ſince nothing of which we can form a clear and diſtinct idea is abſurd and impoſſible. But to form the idea of an object, and to form an idea ſimply is the ſame thing; the reference of the idea to an object being an extraneous denomination, of which in itſelf it bears no mark or character. Now as 'tis impoſſible to form an idea of an object, that is poſſeſt of quantity and quality, and yet is poſſeſt of no preciſe degree of either; it follows, that there is an equal impoſſibility of forming an idea, that is not limited and confin'd in both theſe particulars. Abſtract ideas are therefore in themſelves individual, however they may become general in their [43] repreſentation. The image in the mind is only that of a particular object, tho' the application of it in our reaſoning be the ſame, as if it were univerſal.

THIS application of ideas beyond their nature proceeds from our collecting all their poſſible degrees of quantity and quality in ſuch an imperfect manner as may ſerve the purpoſes of life, which is the ſecond pro⯑poſition I propos'd to explain. When we have found a reſemblance among ſeveral ob⯑jects, that often occur to us, we apply the ſame name to all of them, whatever differ⯑ences we may obſerve in the degrees of their quantity and quality, and whatever other differences may appear among them. After we have acquired a cuſtom of this kind, the hearing of that name revives the idea of one of theſe objects, and makes the imagination conceive it with all its particular circum⯑ſtances and proportions. But as the ſame word is ſuppos'd to have been frequently applied to other individuals, that are diffe⯑rent in many reſpects from that idea, which is immediately preſent to the mind; the word not being able to revive the idea of all theſe individuals, but only touches the ſoul, if I may be allow'd ſo to ſpeak, and re⯑vives that cuſtom, which we have acquir'd [44] by ſurveying them. They are not really and in fact preſent to the mind, but only in power; nor do we draw them all out diſtinctly in the imagination, but keep ourſelves in a readineſs to ſurvey any of them, as we may be prompted by a pre⯑ſent deſign or neceſſity. The word raiſes up an individual idea, along with a cer⯑tain cuſtom; and that cuſtom produces any other individual one, for which we may have occaſion. But as the production of all the ideas, to which the name may be ap⯑ply'd, is in moſt caſes impoſſible, we abridge that work by a more partial conſideration, and find but few inconveniences to ariſe in our reaſoning from that abridgment.

FOR this is one of the moſt extraordi⯑nary circumſtances in the preſent affair, that after the mind has produc'd an individual idea, upon which we reaſon, the attendant cuſtom, reviv'd by the general or abſtract term, readily ſuggeſts any other individual, if by chance we form any reaſoning, that agrees not with it. Thus ſhou'd we men⯑tion the word, triangle, and form the idea of a particular equilateral one to correſpond to it, and ſhou'd we afterwards aſſert, that the three angles of a triangle are equal to each other, the other individuals of a ſcalenum [45] and iſoceles, which we over-look'd at firſt, immediately crowd in upon us, and make us perceive the falſhood of this propoſition, tho' it be true with relation to that idea, which we had form'd. If the mind ſug⯑geſts not always theſe ideas upon occaſion, it proceeds from ſome imperfection in its faculties; and ſuch a one as is often the ſource of falſe reaſoning and ſophiſtry. But this is principally the caſe with thoſe ideas which are abſtruſe and compounded. On other occaſions the cuſtom is more entire, and 'tis ſeldom we run into ſuch errors.

NAY ſo entire is the cuſtom, that the very ſame idea may be annext to ſeveral dif⯑ferent words, and may be employ'd in dif⯑ferent reaſonings, without any danger of miſtakes. Thus the idea of an equilateral triangle of an inch perpendicular may ſerve us in talking of a figure, of a rectilineal figure, of a regular figure, of a triangle, and of an equilateral triangle. All theſe terms, therefore, are in this caſe attended with the ſame idea; but as they are wont to be ap⯑ply'd in a greater or leſſer compaſs, they ex⯑cite their particular habits, and thereby keep the mind in a readineſs to obſerve, that no concluſion be form'd contrary to any ideas, which are uſually compriz'd under them.

[46] BEFORE thoſe habits have become en⯑tirely perfect, perhaps the mind may not be content with forming the idea of only one individual, but may run over ſeveral, in or⯑der to make itſelf comprehend its own meaning, and the compaſs of that collection, which it intends to expreſs by the general term. That we may fix the meaning of the word, figure, we may revolve in our mind the ideas of circles, ſquares, paralelograms, triangles of different ſizes and proportions, and may not reſt on one image or idea. However this may be, 'tis certain that we form the idea of individuals, whenever we uſe any general term; that we ſeldom or never can exhauſt theſe individuals; and that thoſe, which remain, are only repreſented by means of that habit, by which we recal them, whenever any preſent occaſion requires it. This then is the nature of our abſtract ideas and general terms; and 'tis after this manner we account for the foregoing para⯑dox, that ſome ideas are particular in their nature, but general in their repreſentation. A particular idea becomes general by being annex'd to a general term; that is, to a term, which from a cuſtomary conjunction has a relation to many other particular ideas, and readily recals them in the imagination.

[47] THE only difficulty, that can remain on this ſubject, muſt be with regard to that cuſtom, which ſo readily recals every par⯑ticular idea, for which we may have oc⯑caſion, and is excited by any word or ſound, to which we commonly annex it. The moſt proper method, in my opinion, of giving a ſatisfactory explication of this act of the mind, is by producing other inſtan⯑ces, which are analogous to it, and other principles, which facilitate its operation. To explain the ultimate cauſes of our mental actions is impoſſible. 'Tis ſufficient, if we can give any ſatisfactory account of them from experience and analogy.

FIRST then I obſerve, that when we mention any great number, ſuch as a thou⯑ſand, the mind has generally no adequate idea of it, but only a power of producing ſuch an idea, by its adequate idea of the decimals, under which the number is com⯑prehended. This imperfection, however in our ideas, is never felt in our reaſonings; which ſeems to be an inſtance parallel to the preſent one of univerſal ideas.

SECONDLY, we have ſeveral inſtances of habits, which may be reviv'd by one ſingle word; as when a perſon, who has by rote any periods of a diſcourſe, or any number [48] of verſes, will be put in remembrance of the whole, which he is at a loſs to recollect, by that ſingle word or expreſſion, with which they begin.

THIRDLY, I believe every one, who ex⯑amines the ſituation of his mind in reaſon⯑ing, will agree with me, that we do not annex diſtinct and compleat ideas to every term we make uſe of, and that in talking of government, church, negotiation, conqueſt, we ſeldom ſpread out in our minds all the ſimple ideas, of which theſe complex ones are compos'd. 'Tis however obſervable, that notwithſtanding this imperfection we may avoid talking nonſenſe on theſe ſubjects, and may perceive any repugnance among the ideas, as well as if we had a full compre⯑henſion of them. Thus if inſtead of ſay⯑ing, that in war the weaker have always recourſe to negotiation, we ſhou'd ſay, that they have always recourſe to conqueſt, the cuſtom, which we have acquir'd of attri⯑buting certain relations to ideas, ſtill follows the words, and makes us immediately per⯑ceive the abſurdity of that propoſition; in the ſame manner as one particular idea may ſerve us in reaſoning concerning other ideas, however different from it in ſeveral circum⯑ſtances.

[49] FOURTHLY, As the individuals are col⯑lected together, and plac'd under a general term with a view to that reſemblance, which they bear to each other, this relation muſt facilitate their entrance in the imagination, and make them be ſuggeſted more readily upon occaſion. And indeed if we conſider the common progreſs of the thought, either in reflection or converſation, we ſhall find great reaſon to be ſatisfy'd in this particular. Nothing is more admirable, than the readi⯑neſs, with which the imagination ſuggeſts its ideas, and preſents them at the very in⯑ſtant, in which they become neceſſary or uſeful. The fancy runs from one end of the univerſe to the other in collecting thoſe ideas, which belong to any ſubject. One would think the whole intellectual world of ideas was at once ſubjected to our view, and that we did nothing but pick out ſuch as were moſt proper for our purpoſe. There may not, however, be any preſent, beſide thoſe very ideas, that are thus collected by a kind of magical faculty in the ſoul, which, tho' it be always moſt perfect in the greateſt geniuſes, and is properly what we call a genius, is however inexplicable by the utmoſt efforts of human underſtand⯑ing.

[50] PERHAPS theſe four reflections may help to remove all difficulties to the hypotheſis I have propos'd concerning abſtract ideas, ſo contrary to that, which has hitherto pre⯑vail'd in philoſophy. But to tell the truth I place my chief confidence in what I have already prov'd concerning the impoſſibility of general ideas, according to the common method of explaining them. We muſt cer⯑tainly ſeek ſome new ſyſtem on this head, and there plainly is none beſide what I have propos'd. If ideas be particular in their na⯑ture, and at the ſame time finite in their number, 'tis only by cuſtom they can be⯑come general in their repreſentation, and contain an infinite number of other ideas under them.

BEFORE I leave this ſubject I ſhall em⯑ploy the ſame principles to explain that di⯑ſtinction of reaſon, which is ſo much talk'd of, and is ſo little underſtood, in the ſchools. Of this kind is the diſtinction betwixt figure and the body figur'd; motion and the body mov'd. The difficulty of explaining this diſtinction ariſes from the principle above explain'd, that all ideas, which are different, are ſeparable. For it follows from thence, that if the figure be different from the body, their ideas muſt be ſeparable as well as di⯑ſtinguiſhable; [51] if they be not different, their ideas can neither be ſeparable nor diſtinguiſh⯑able. What then is meant by a diſtinction of reaſon, ſince it implies neither a diffe⯑rence nor ſeparation?

TO remove this difficulty we muſt have recourſe to the foregoing explication of ab⯑ſtract ideas. 'Tis certain that the mind wou'd never have dream'd of diſtinguiſhing a figure from the body figur'd, as being in reality neither diſtinguiſhable, nor different, nor ſeparable; did it not obſerve, that even in this ſimplicity there might be contain'd many different reſemblances and relations. Thus when a globe of white marble is preſent⯑ed, we receive only the impreſſion of a white colour diſpos'd in a certain form, nor are we able to ſeparate and diſtinguiſh the colour from the form. But obſerving afterwards a globe of black marble and a cube of white, and comparing them with our former ob⯑ject, we find two ſeparate reſemblances, in what formerly ſeem'd, and really is, perfectly inſeparable. After a little more practice of this kind, we begin to diſtinguiſh the figure from the colour by a diſtinction of reaſon; that is, we conſider the figure and colour to⯑gether, ſince they are in effect the ſame and undiſtinguiſhable; but ſtill view them in [52] different aſpects, according to the reſem⯑blances, of which they are ſuſceptible. When we wou'd conſider only the figure of the globe of white marble, we form in reality an idea both of the figure and colour, but tacitly carry our eye to its reſemblance with the globe of black marble: And in the ſame manner, when we wou'd conſider its colour only, we turn our view to its reſemblance with the cube of white marble. By this means we accompany our ideas with a kind of reflection, of which cuſtom renders us, in a great meaſure, inſenſible. A perſon, who deſires us to conſider the figure of a globe of white marble without thinking on its colour, deſires an impoſſibility; but his meaning is, that we ſhou'd conſider the colour and figure together, but ſtill keep in our eye the reſemblance to the globe of black marble, or that to any other globe of whatever colour or ſubſtance.

SECT. I. Of the infinite diviſibility of our ideas of ſpace and time.

WHATEVER has the air of a paradox, and is contrary to the firſt and moſt unprejudic'd notions of mankind is often greedily embrac'd by philoſophers, as ſhewing the ſuperiority of their ſcience, which cou'd diſcover opinions ſo remote from vulgar conception. On the other hand, any thing propos'd to us, which cauſes ſurprize and admiration, gives ſuch a ſatisfaction to the mind, that it indulges it⯑ſelf in thoſe agreeable emotions, and will never be perſwaded that its pleaſure is entirely without foundation. From theſe diſpoſitions in philoſophers and their diſci⯑ples [54] ariſes that mutual complaiſance betwixt them; while the former furniſh ſuch plenty of ſtrange and unaccountable opinions, and the latter ſo readily believe them. Of this mutual complaiſance I cannot give a more evident inſtance than in the doctrine of in⯑finite diviſibility, with the examination of which I ſhall begin this ſubject of the ideas of ſpace and time.

'TIS univerſally allow'd, that the capa⯑city of the mind is limited, and can never attain a full and adequate conception of in⯑finity: And tho' it were not allow'd, 'twou'd be ſufficiently evident from the plaineſt ob⯑ſervation and experience. 'Tis alſo obvious, that whatever is capable of being divided in infinitum, muſt conſiſt of an infinite num⯑ber of parts, and that 'tis impoſſible to ſet any bounds to the number of parts, without ſetting bounds at the ſame time to the di⯑viſion. It requires ſcarce any induction to conclude from hence, that the idea, which we form of any finite quality, is not infi⯑nitely diviſible, but that by proper diſtinc⯑tions and ſeparations we may run up this idea to inferior ones, which will be per⯑fectly ſimple and indiviſible. In rejecting the infinite capacity of the mind, we ſup⯑poſe it may arrive at an end in the diviſion [55] of its ideas; nor are there any poſſible means of evading the evidence of this concluſion.

'TIS therefore certain, that the imagi⯑nation reaches a minimum, and may raiſe up to itſelf an idea, of which it cannot con⯑ceive any ſub-diviſion, and which cannot be diminiſhed without a total annihilation. When you tell me of the thouſandth and ten thouſandth part of a grain of ſand, I have a diſtinct idea of theſe numbers and of their different proportions; but the images, which I form in my mind to repreſent the things themſelves, are nothing different from each other, nor inferior to that image, by which I repreſent the grain of ſand itſelf, which is ſuppos'd ſo vaſtly to exceed them. What conſiſts of parts is diſtinguiſhable into them, and what is diſtinguiſhable is ſepa⯑rable. But whatever we may imagine of the thing, the idea of a grain of ſand is not diſtinguiſhable, nor ſeparable into twenty, much leſs into a thouſand, ten thouſand, or an infinite number of different ideas.

'TIS the ſame caſe with the impreſſions of the ſenſes as with the ideas of the ima⯑gination. Put a ſpot of ink upon paper, fix your eye upon that ſpot, and retire to ſuch a diſtance, that at laſt you loſe ſight of it; 'tis plain, that the moment before it [56] vaniſh'd the image or impreſſion was per⯑fectly indiviſible. 'Tis not for want of rays of light ſtriking on our eyes, that the mi⯑nute parts of diſtant bodies convey not any ſenſible impreſſion; but becauſe they are re⯑mov'd beyond that diſtance, at which their impreſſions were reduc'd to a minimum, and were incapable of any farther diminution. A microſcope or teleſcope, which renders them viſible, produces not any new rays of light, but only ſpreads thoſe, which always flow'd from them; and by that means both gives parts to impreſſions, which to the naked eye appear ſimple and uncompounded, and advances to a minimum, what was for⯑merly imperceptible.

WE may hence diſcover the error of the common opinion, that the capacity of the mind is limited on both ſides, and that 'tis impoſſible for the imagination to form an adequate idea, of what goes beyond a cer⯑tain degree of minuteneſs as well as of great⯑neſs. Nothing can be more minute, than ſome ideas, which we form in the fancy; and images, which appear to the ſenſes; ſince there are ideas and images perfectly ſimple and indiviſible. The only defect of our ſenſes is, that they give us diſpropor⯑tion'd images of things, and repreſent as mi⯑nute [57] and uncompounded what is really great and compos'd of a vaſt number of parts. This miſtake we are not ſenſible of; but taking the impreſſions of thoſe minute ob⯑jects, which appear to the ſenſes, to be equal or nearly equal to the objects, and finding by reaſon, that there are other objects vaſtly more minute, we too haſtily conclude, that theſe are inferior to any idea of our imagi⯑nation or impreſſion of our ſenſes. This however is certain, that we can form ideas, which ſhall be no greater than the ſmalleſt atom of the animal ſpirits of an inſect a thouſand times leſs than a mite: And we ought rather to conclude, that the difficulty lies in enlarging our conceptions ſo much as to form a juſt notion of a mite, or even of an inſect a thouſand times leſs than a mite. For in order to form a juſt notion of theſe animals, we muſt have a diſtinct idea repre⯑ſenting every part of them; which, accord⯑ing to the ſyſtem of infinite diviſibility, is utterly impoſſible, and according to that of indiviſible parts or atoms, is extremely diffi⯑cult, by reaſon of the vaſt number and mul⯑tiplicity of theſe parts.

SECT. II. Of the infinite diviſibility of ſpace and time.

WHerever ideas are adequate repreſen⯑tations of objects, the relations, con⯑tradictions and agreements of the ideas are all applicable to the objects; and this we may in general obſerve to be the foundation of all human knowledge. But our ideas are ade⯑quate repreſentations of the moſt minute partsof extenſion; and thro' whatever divi⯑ſions and ſubdiviſions we may ſuppoſe theſe parts to be arriv'd at, they can never become inferior to ſome ideas, which we form. The plain conſequence is, that whatever appears impoſſible and contradictory upon the com⯑pariſon of theſe ideas, muſt be really im⯑poſſible and contradictory, without any far⯑ther excuſe or evaſion.

EVERY thing capable of being infinitely divided contains an infinite number of parts; otherwiſe the diviſion would be ſtopt ſhort by the indiviſible parts, which we ſhould immediately arrive at. If therefore any fi⯑nite extenſion be infinitely diviſible, it can be no contradiction to ſuppoſe, that a finite extenſion contains an infinite number of [59] parts: And vice verſa, if it be a contradic⯑tion to ſuppoſe, that a finite extenſion con⯑tains an infinite number of parts, no finite extenſion can be infinitely diviſible. But that this latter ſuppoſition is abſurd, I eaſily con⯑vince myſelf by the conſideration of my clear ideas. I firſt take the leaſt idea I can form of a part of extenſion, and being certain that there is nothing more minute than this idea, I conclude, that whatever I diſcover by its means muſt be a real quality of extenſion. I then repeat this idea once, twice, thrice, &c. and find the compound idea of exten⯑ſion, ariſing from its repetition, always to augment, and become double, triple, qua⯑druple, &c. till at laſt it ſwells up to a conſi⯑derable bulk, greater or ſmaller, in propor⯑tion as I repeat more or leſs the ſame idea. When I ſtop in the addition of parts, the idea of extenſion ceaſes to augment; and were I to carry on the addition in infinitum, I clearly perceive, that the idea of extenſion muſt alſo become infinite. Upon the whole, I con⯑clude, that the idea of an infinite number of parts is individually the ſame idea with that of an infinite extenſion; that no fi⯑nite extenſion is capable of containing an infinite number of parts; and conſequently [60] that no finite extenſion is infinitely divi⯑ſible ^*.

I MAY ſubjoin another argument propos'd by a noted author ^†, which ſeems to me very ſtrong and beautiful. 'Tis evident, that ex⯑iſtence in itſelf belongs only to unity, and is never applicable to number, but on ac⯑count of the unites, of which the number is compos'd. Twenty men may be ſaid to exiſt; but 'tis only becauſe one, two, three, four, &c. are exiſtent; and if you deny the exiſtence of the latter, that of the former falls of courſe. 'Tis therefore utterly abſurd to ſuppoſe any number to exiſt, and yet deny the exiſtence of unites; and as extenſion is always a number, according to the common ſentiment of metaphyſicians, and never re⯑ſolves itſelf into any unite or indiviſible quan⯑tity, it follows, that extenſion can never at all exiſt. 'Tis in vain to reply, that any de⯑terminate quantity of extenſion is an unite; [61] but ſuch-a-one as admits of an infinite number of fractions, and is inexhauſtible in its ſub-diviſions. For by the ſame rule theſe twenty men may be conſider'd as an unite. The whole globe of the earth, nay the whole univerſe may be conſider'd as an unite. That term of unity is merely a fic⯑titious denomination, which the mind may apply to any quantity of objects it collects together; nor can ſuch an unity any more exiſt alone than number can, as being in reality a true number. But the unity, which can exiſt alone, and whoſe exiſtence is ne⯑ceſſary to that of all number, is of another kind, and muſt be perfectly indiviſible, and incapable of being reſolved into any leſſer unity.

ALL this reaſoning takes place with re⯑gard to time; along with an additional ar⯑gument, which it may be proper to take notice of. 'Tis a property inſeparable from time, and which in a manner conſtitutes its eſſence, that each of its parts ſucceeds an⯑other, and that none of them, however con⯑tiguous, can ever be co-exiſtent. For the ſame reaſon, that the year 1737. cannot con⯑cur with the preſent year 1738. every mo⯑ment muſt be diſtinct from, and poſterior or antecedent to another. 'Tis certain then, [62] that time, as it exiſts, muſt be compos'd of indiviſible moments. For if in time we could never arrive at an end of diviſion, and if each moment, as it ſucceeds another, were not perfectly ſingle and indiviſible, there would be an infinite number of co-exiſtent moments, or parts of time; which I be⯑lieve will be allow'd to be an arrant contra⯑diction.

THE infinite diviſibility of ſpace implies that of time, as is evident from the nature of motion. If the latter, therefore, be im⯑poſſible, the former muſt be equally ſo.

I DOUBT not but it will readily be al⯑low'd by the moſt obſtinate defender of the doctrine of infinite diviſibility, that theſe argu⯑ments are difficulties, and that 'tis impoſſible to give any anſwer to them which will be perfect⯑ly clear and ſatisfactory. But here we may obſerve, that nothing can be more abſurd, than this cuſtom of calling a difficulty what pretends to be a demonſtration, and endea⯑vouring by that means to elude its force and evidence. 'Tis not in demonſtrations as in probabilities, that difficulties can take place, and one argument counter-ballance another, and diminiſh its authority. A demonſtra⯑tion, if juſt, admits of no oppoſite difficul⯑ty; and if not juſt, 'tis a mere ſophiſm, and [63] conſequently can never be a difficulty. 'Tis either irreſiſtible, or has no manner of force. To talk therefore of objections and replies, and ballancing of arguments in ſuch a que⯑ſtion as this, is to confeſs, either that human reaſon is nothing but a play of words, or that the perſon himſelf, who talks ſo, has not a capacity equal to ſuch ſubjects. De⯑monſtrations may be difficult to be compre⯑hended, becauſe of the abſtractedneſs of the ſubject; but can never have any ſuch difficul⯑ties as will weaken their authority, when once they are comprehended.

'TIS true, mathematicians are wont to ſay, that there are here equally ſtrong ar⯑guments on the other ſide of the queſtion, and that the doctrine of indiviſible points is alſo liable to unanſwerable objections. Be⯑fore I examine theſe arguments and objections in detail, I will here take them in a body, and endeavour by a ſhort and deciſive rea⯑ſon to prove at once, that 'tis utterly im⯑poſſible they can have any juſt foundation.

'TIS an eſtabliſh'd maxim in metaphy⯑ſics, That whatever the mind clearly conceives includes the idea of poſſible exiſtence, or in other words, that nothing we imagine is ab⯑ſolutely impoſſible. We can form the idea of a golden mountain, and from thence conclude [64] that ſuch a mountain may actually exiſt. We can form no idea of a mountain with⯑out a valley, and therefore regard it as im⯑poſſible.

NOW 'tis certain we have an idea of ex⯑tenſion; for otherwiſe why do we talk and reaſon concerning it? 'Tis likewiſe certain, that this idea, as conceiv'd by the imagina⯑tion, tho' diviſible into parts or inferior ideas, is not infinitely diviſible, nor conſiſts of an in⯑finite number of parts: For that exceeds the comprehenſion of our limited capacities. Here then is an idea of extenſion, which conſiſts of parts or inferior ideas, that are perfectly indiviſible: conſequently this idea implies no contradiction: conſequently 'tis poſſible for extenſion really to exiſt conformable to it: and conſequently all the arguments employ'd againſt the poſſibility of mathematical points are mere ſcholaſtick quibbles, and unwor⯑thy of our attention.

THESE conſequences we may carry one ſtep farther, and conclude that all the pre⯑tended demonſtrations for the infinite diviſi⯑bility of extenſion are equally ſophiſtical; ſince 'tis certain theſe demonſtrations cannot be juſt without proving the impoſſibility of mathematical points; which 'tis an evident abſurdity to pretend to.

SECT. III. Of the other qualities of our ideas of ſpace and time.

NO diſcovery cou'd have been made more happily for deciding all con⯑troverſies concerning ideas, than that above⯑mention'd, that impreſſions always take the precedency of them, and that every idea, with which the imagination is furniſh'd, firſt makes its appearance in a correſpondent im⯑preſſion. Theſe latter perceptions are all ſo clear and evident, that they admit of no controverſy; tho' many of our ideas are ſo obſcure, that 'tis almoſt impoſſible even for the mind, which forms them, to tell ex⯑actly their nature and compoſition. Let us apply this principle, in order to diſcover far⯑ther the nature of our ideas of ſpace and time

UPON opening my eyes, and turning them to the ſurrounding objects, I perceive many viſible bodies; and upon ſhutting them again, and conſidering the diſtance betwixt theſe bodies, I acquire the idea of extenſion. As every idea is deriv'd from ſome impreſſion, which is exactly ſimilar to it, the impreſſi⯑ons [66] ſimilar to this idea of extenſion, muſt either be ſome ſenſations deriv'd from the ſight, or ſome internal impreſſions ariſing from theſe ſenſations.

OUR internal impreſſions are our paſſi⯑ons, emotions, deſires and averſions; none of which, I believe, will ever be aſſerted to be the model, from which the idea of ſpace is deriv'd. There remains therefore nothing but the ſenſes, which can convey to us this original impreſſion. Now what impreſſion do our ſenſes here convey to us? This is the principal queſtion, and decides without ap⯑peal concerning the nature of the idea.

THE table before me is alone ſufficient by its view to give me the idea of ex⯑tenſion. This idea, then, is borrow'd from, and repreſents ſome impreſſion, which this moment appears to the ſenſes. But my ſenſes convey to me only the impreſſions of colour'd points, diſpos'd in a certain manner. If the eye is ſenſible of any thing farther, I deſire it may be pointed out to me. But if it be impoſſible to ſhew any thing far⯑ther, we may conclude with certainty, that the idea of extenſion is nothing but a copy of theſe colour'd points, and of the manner of their appearance.

[67] SUPPOSE that in the extended object, or compoſition of colour'd points, from which we firſt receiv'd the idea of extenſion, the points were of a purple colour; it follows, that in every repetition of that idea we wou'd not only place the points in the ſame order with reſpect to each other, but alſo beſtow on them that preciſe colour, with which alone we are acquainted. But afterwards having experience of the other colours of violet, green, red, white, black, and of all the different compoſitions of theſe, and find⯑ing a reſemblance in the diſpoſition of co⯑lour'd points, of which they are compos'd, we omit the peculiarities of colour, as far as poſſible, and found an abſtract idea mere⯑ly on that diſpoſition of points, or manner of appearance, in which they agree. Nay even when the reſemblance is carry'd be⯑yond the objects of one ſenſe, and the im⯑preſſions of touch are found to be ſimilar to thoſe of ſight in the diſpoſition of their parts; this does not hinder the abſtract idea from repreſenting both, upon account of their reſemblance. All abſtract ideas are really nothing but particular ones, conſi⯑der'd in a certain light; but being annexed to general terms, they are able to repreſent a vaſt variety, and to comprehend objects, [68] which, as they are alike in ſome particu⯑lars, are in others vaſtly wide of each other.

THE idea of time, being deriv'd from the ſucceſſion of our perceptions of every kind, ideas as well as impreſſions, and im⯑preſſions of reflection as well as of ſenſation, will afford us an inſtance of an abſtract idea, which comprehends a ſtill greater variety than that of ſpace, and yet is repreſented in the fancy by ſome particular individual idea of a determinate quantity and quality.

As 'tis from the diſpoſition of viſible and tangible objects we receive the idea of ſpace, ſo from the ſucceſſion of ideas and impreſ⯑ſions we form the idea of time, nor is it poſſible for time alone ever to make its ap⯑pearance, or be taken notice of by the mind. A man in a ſound ſleep, or ſtrongly occu⯑py'd with one thought, is inſenſible of time; and according as his perceptions ſucceed each other with greater or leſs rapidity, the ſame duration appears longer or ſhorter to his imagination. It has been remark'd by a ^* great philoſopher, that our perceptions have certain bounds in this particular, which are fix'd by the original nature and conſtitu⯑tion of the mind, and beyond which no in⯑fluence [69] of external objects on the ſenſes is ever able to haſten or retard our thought. If you wheel about a burning coal with rapidity, it will preſent to the ſenſes an image of a circle of fire; nor will there ſeem to be any interval of time betwixt its revolu⯑tions; meerly becauſe 'tis impoſſible for our perceptions to ſucceed each other with the ſame rapidity, that motion may be commu⯑nicated to external objects. Wherever we have no ſucceſſive perceptions, we have no notion of time, even tho' there be a real ſucceſſion in the objects. From theſe phae⯑nomina, as well as from many others, we may conclude, that time cannot make its ap⯑pearance to the mind, either alone, or at⯑tended with a ſteady unchangeable object, but is always diſcover'd by ſome perceivable ſucceſſion of changeable objects.

To confirm this we may add the follow⯑ing argument, which to me ſeems perfectly deciſive and convincing. 'Tis evident, that time or duration conſiſts of different parts: For otherwiſe we cou'd not conceive a longer or ſhorter duration. 'Tis alſo evident, that theſe parts are not co-exiſtent: For that quality of the co-exiſtence of parts belongs to extenſion, and is what diſtinguiſhes it from duration. Now as time is compos'd [70] of parts, that are not co-exiſtent; an un⯑changeable object, ſince it produces none but co-exiſtent impreſſions, produces none that can give us the idea of time; and conſe⯑quently that idea muſt be deriv'd from a ſucceſſion of changeable objects, and time in its firſt appearance can never be ſever'd from ſuch a ſucceſſion.

HAVING therefore found, that time in its firſt appearance to the mind is always conjoin'd with a ſucceſſion of changeable ob⯑jects, and that otherwiſe it can never fall under our notice, we muſt now examine whether it can be conceiv'd without our con⯑ceiving any ſucceſſion of objects, and whether it can alone form a diſtinct idea in the ima⯑gination.

IN order to know whither any objects, which are join'd in impreſſion, be ſeparable in idea, we need only conſider, if they be different from each other; in which caſe, 'tis plain they may be conceiv'd apart. Every thing, that is different, it diſtinguiſhable; and every thing, that is diſtinguiſhable, may be ſeparated, according to the maxims above⯑explain'd. If on the contrary they be not different, they are not diſtinguiſhable; and if they be not diſtinguiſhable, they cannot be ſeparated. But this is preciſely the caſe [71] with reſpect to time, compar'd with our ſucceſſive perceptions. The idea of time is not deriv'd from a particular impreſſion mix'd up with others, and plainly diſtinguiſhable from them; but ariſes altogether from the manner, in which impreſſions appear to the mind, without making one of the number. Five notes play'd on a flute give us the impreſſion and idea of time; tho' time be not a ſixth impreſſion, which preſents itſelf to the hearing or any other of the ſenſes. Nor is it a ſixth impreſſion, which the mind by reflection finds in itſelf. Theſe five ſounds making their appearance in this par⯑ticular manner, excite no emotion in the mind, nor produce an affection of any kind, which being obſerv'd by it can give riſe to a new idea. For that is neceſſary to produce a new idea of reflection, nor can the mind, by revolving over a thouſand times all its ideas of ſenſation, ever extract from them any new original idea, unleſs nature has ſo fram'd its faculties, that it feels ſome new original impreſſion ariſe from ſuch a con⯑templation. But here it only takes notice of the manner, in which the different ſounds make their appearance; and that it may af⯑terwards conſider without conſidering theſe particular ſounds, but may conjoin it with [72] any other objects. The ideas of ſome objects it certainly muſt have, nor is it poſſible for it without theſe ideas ever to arrive at any conception of time; which ſince it appears not as any primary diſtinct impreſſion, can plainly be nothing but different ideas, or im⯑preſſions, or objects diſpos'd in a certain man⯑ner, that is, ſucceeding each other.

I KNOW there are ſome who pretend, that the idea of duration is applicable in a proper ſenſe to objects, which are perfectly unchangeable; and this I take to be the com⯑mon opinion of philoſophers as well as of the vulgar. But to be convinc'd of its falſe⯑hood we need but reflect on the foregoing concluſion, that the idea of duration is al⯑ways deriv'd from a ſucceſſion of change⯑able objects, and can never be convey'd to the mind by any thing ſtedfaſt and unchange⯑able. For it inevitably follows from thence, that ſince the idea of duration cannot be de⯑riv'd from ſuch an object, it can never in any propriety or exactneſs be apply'd to it, nor can any thing unchangeable be ever ſaid to have duration. Ideas always repreſent the objects or impreſſions, from which they are deriv'd, and can never without a fiction re⯑preſent or be apply'd to any other. By what fiction we apply the idea of time, even to [73] what is unchangeable, and ſuppoſe, as is common, that duration is a meaſure of reſt as well as of motion, we ſhall conſider ^* after⯑wards.

THERE is another very deciſive argu⯑ment, which eſtabliſhes the preſent doctrine concerning our ideas of ſpace and time, and is founded only on that ſimple principle, that our ideas of them are compounded of parts, which are indiviſible. This argument may be worth the examining.

EVERY idea, that is diſtinguiſhable, being alſo ſeparable, let us take one of thoſe ſimple indiviſible ideas, of which the compound one of extenſion is form'd, and ſeparating it from all others, and conſidering it apart, let us form a judgment of its nature and quali⯑ties.

'TIS plain it is not the idea of extenſion. For the idea of extenſion conſiſts of parts; and this idea, according to the ſuppoſition, is perfectly ſimple and indiviſible. Is it there⯑fore nothing? That is abſolutely impoſſible. For as the compound idea of extenſion, which is real, is compos'd of ſuch ideas; were theſe ſo many non-entities, there wou'd be a real exiſtence compos'd of non-entities; which is abſurd. Here therefore I muſt aſk, [74] What is our idea of a ſimple and indiviſible point? No wonder if my anſwer appear ſomewhat new, ſince the queſtion itſelf has ſcarce ever yet been thought of. We are wont to diſpute concerning the nature of mathematical points, but ſeldom concerning the nature of their ideas.

THE idea of ſpace is convey'd to the mind by two ſenſes, the ſight and touch; nor does any thing ever appear extended, that is not either viſible or tangible. That compound impreſſion, which repreſents ex⯑tenſion, conſiſts of ſeveral leſſer impreſſions, that are indiviſible to the eye or feeling, and may be call'd impreſſions of atoms or cor⯑puſcles endow'd with colour and ſolidity. But this is not all. 'Tis not only requiſite, that theſe atoms ſhou'd be colour'd or tan⯑gible, in order to diſcover themſelves to our ſenſes; 'tis alſo neceſſary we ſhou'd preſerve the idea of their colour or tangibility in or⯑der to comprehend them by our imagina⯑tion. There is nothing but the idea of their colour or tangibility, which can render them conceivable by the mind. Upon the re⯑moval of the ideas of theſe ſenſible qualities, they are utterly annihilated to the thought or imagination.

[75] NOW ſuch as the parts are, ſuch is the whole. If a point be not conſider'd as colour'd or tangible, it can convey to us no idea; and conſequently the idea of exten⯑ſion, which is compos'd of the ideas of theſe points, can never poſſibly exiſt. But if the idea of extenſion really can exiſt, as we are conſcious it does, its parts muſt alſo exiſt; and in order to that, muſt be conſider'd as colour'd or tangible. We have therefore no idea of ſpace or extenſion, but when we regard it as an object either of our ſight or feeling.

THE ſame reaſoning will prove, that the indiviſible moments of time muſt be fill'd with ſome real object or exiſtence, whoſe ſucceſſion forms the duration, and makes it be conceivable by the mind.

SECT. IV. Objections anſwer'd.

OUR ſyſtem concerning ſpace and time conſiſts of two parts, which are in⯑timately connected together. The firſt de⯑pends on this chain of reaſoning. The ca⯑pacity of the mind is not infinite; conſe⯑quently no idea of extenſion or duration con⯑ſiſts [76] of an infinite number of parts or infe⯑rior ideas, but of a finite number, and theſe ſimple and indiviſible: 'Tis therefore poſ⯑ſible for ſpace and time to exiſt con⯑formable to this idea: And if it be poſſible, 'tis certain they actually do exiſt conform⯑able to it; ſince their infinite diviſibility is utterly impoſſible and contradictory.

THE other part of our ſyſtem is a con⯑ſequence of this. The parts, into which the ideas of ſpace and time reſolve themſelves, become at laſt indiviſible; and theſe indivi⯑ſible parts, being nothing in themſelves, are inconceivable when not fill'd with ſomething real and exiſtent. The ideas of ſpace and time are therefore no ſeparate or diſtinct ideas, but merely thoſe of the manner or order, in which objects exiſt: Or, in other words, 'tis impoſſible to conceive either a vacuum and extenſion without matter, or a time, when there was no ſucceſſion or change in any real exiſtence. The intimate connexion betwixt theſe parts of our ſyſtem is the reaſon why we ſhall examine together the objections, which have been urg'd againſt both of them, beginning with thoſe againſt the finite di⯑viſibility of extenſion.

I. THE firſt of theſe objections, which I ſhall take notice of, is more proper to prove [77] this connexion and dependance of the one part upon the other, than to deſtroy either of them. It has often been maintain'd in the ſchools, that extenſion muſt be diviſible, in infinitum, becauſe the ſyſtem of mathe⯑matical points is abſurd; and that ſyſtem is abſurd, becauſe a mathematical point is a non-entity, and conſequently can never by its conjunction with others form a real ex⯑iſtence. This wou'd be perfectly deciſive, were there no medium betwixt the infinite diviſibility of matter, and the non-entity of mathematical points. But there is evidently a medium, viz. the beſtowing a colour or ſolidity on theſe points; and the abſurdity of both the extremes is a demonſtration of the truth and reality of this medium. The ſyſtem of phyſical points, which is another medium, is too abſurd to need a refutation. A real extenſion, ſuch as a phyſical point is ſuppos'd to be, can never exiſt without parts, different from each other; and where⯑ever objects are different, they are diſtinguiſh⯑able and ſeparable by the imagination.

II. THE ſecond objection is deriv'd from the neceſſity there wou'd be of penetration, if extenſion conſiſted of mathematical points. A ſimple and indiviſible atom, that touches another, muſt neceſſarily penetrate it; for [78] 'tis impoſſible it can touch it by its external parts, from the very ſuppoſition of its per⯑fect ſimplicity, which excludes all parts. It muſt therefore touch it intimately, and in its whole eſſence, ſecundum ſe, tota, & tota⯑liter; which is the very definition of pene⯑tration. But penetration is impoſſible: Ma⯑thematical points are of conſequence equally impoſſible.

I ANSWER this objection by ſubſtituting a juſter idea of penetration. Suppoſe two bodies containing no void within their cir⯑cumference, to approach each other, and to unite in ſuch a manner that the body, which reſults from their union, is no more extend⯑ed than either of them; 'tis this we muſt mean when we talk of penetration. But 'tis evident this penetration is nothing but the annihilation of one of theſe bodies, and the preſervation of the other, without our being able to diſtinguiſh particularly which is preſerv'd and which annihilated. Before the approach we have the idea of two bo⯑dies. After it we have the idea only of one. 'Tis impoſſible for the mind to preſerve any notion of difference betwixt two bodies of the ſame nature exiſting in the ſame place at the ſame time.

[79] TAKING then penetration in this ſenſe, for the annihilation of one body upon its approach to another, I aſk any one, if he ſees a neceſſity, that a colour'd or tangi⯑ble point ſhou'd be annihilated upon the ap⯑proach of another colour'd or tangible point? On the contrary, does he not evidently per⯑ceive, that from the union of theſe points there reſults an object, which is compounded and diviſible, and may be diſtinguiſh'd into two parts, of which each preſerves its exi⯑ſtence diſtinct and ſeparate, notwithſtanding its contiguity to the other? Let him aid his fancy by conceiving theſe points to be of different colours, the better to prevent their coalition and confuſion. A blue and a red point may ſurely lie contiguous without any penetration or annihilation. For if they cannot, what poſſibly can become of them? Whether ſhall the red or the blue be anni⯑hilated? Or if theſe colours unite into one, what new colour will they produce by their union?

WHAT chiefly gives riſe to theſe ob⯑jections, and at the ſame time renders it ſo difficult to give a ſatisfactory anſwer to them, is the natural infirmity and unſteadineſs both of our imagination and ſenſes, when em⯑ploy'd on ſuch minute objects. Put a ſpot [80] of ink upon paper, and retire to ſuch a di⯑ſtance, that the ſpot becomes altogether in⯑viſible; you will find, that upon your re⯑turn and nearer approach the ſpot firſt be⯑comes viſible by ſhort intervals; and after⯑wards becomes always viſible; and afterwards acquires only a new force in its colouring without augmenting its bulk; and after⯑wards, when it has encreas'd to ſuch a de⯑gree as to be really extended, 'tis ſtill diffi⯑cult for the imagination to break it into its component parts, becauſe of the uneaſineſs it finds in the conception of ſuch a minute ob⯑ject as a ſingle point. This infirmity af⯑fects moſt of our reaſonings on the pre⯑ſent ſubject, and makes it almoſt impoſſible to anſwer in an intelligible manner, and in proper expreſſions, many queſtions which may ariſe concerning it.

III. THERE have been many objections drawn from the mathematics againſt the indi⯑viſibility of the parts of extenſion; tho' at firſt ſight that ſcience ſeems rather favourable to the preſent doctrine; and if it be contrary in its demonſtrations, 'tis perfectly conformable in its definitions. My preſent buſineſs then muſt be to defend the definitions, and refute the demonſtrations.

[81] A SURFACE is defin'd to be length and breadth without depth: A line to be length without breadth or depth: A point to be what has neither length, breadth nor depth. 'Tis evident that all this is perfectly unin⯑telligible upon any other ſuppoſition than that of the compoſition of extenſion by in⯑diviſible points or atoms. How elſe cou'd any thing exiſt without length, without breadth, or without depth?

TWO different anſwers, I find, have been made to this argument; neither of which is in my opinion ſatisfactory. The firſt is, that the objects of geometry, thoſe ſurfaces, lines and points, whoſe proportions and poſitions it examines, are mere ideas in the mind; and not only never did, but never can exiſt in nature. They never did exiſt; for no one will pretend to draw a line or make a ſurface entirely conformable to the defini⯑tion: They never can exiſt; for we may produce demonſtrations from theſe very ideas to prove, that they are impoſſible.

BUT can any thing be imagin'd more ab⯑ſurd and contradictory than this reaſoning? Whatever can be conceiv'd by a clear and diſtinct idea neceſſarily implies the poſſibi⯑lity of exiſtence; and he who pretends to prove the impoſſibility of its exiſtence by [82] any argument deriv'd from the clear idea, in reality aſſerts, that we have no clear idea of it, becauſe we have a clear idea. 'Tis in vain to ſearch for a contradiction in any thing that is diſtinctly conceiv'd by the mind. Did it imply any contradiction, 'tis impoſ⯑ſible it cou'd ever be conceiv'd.

THERE is therefore no medium betwixt allowing at leaſt the poſſibility of indiviſible points, and denying their idea; and 'tis on this latter principle, that the ſecond anſwer to the foregoing argument is founded. It has been ^* pretended, that tho' it be impoſ⯑ſible to conceive a length without any breadth, yet by an abſtraction without a ſeparation, we can conſider the one without regarding the other; in the ſame manner as we may think of the length of the way betwixt two towns, and overlook its breadth. The length is inſeparable from the breadth both in na⯑ture and in our minds; but this excludes not a partial conſideration, and a diſtinction of reaſon, after the manner above explain'd.

IN reſuting this anſwer I ſhall not inſiſt on the argument, which I have already ſuf⯑ficiently explain'd, that if it be impoſſible for the mind to arrive at a minimum in its ideas, its capacity muſt be infinite, in order [83] to comprehend the infinite number of parts, of which its idea of any extenſion wou'd be compos'd. I ſhall here endeavour to find ſome new abſurdities in this rea⯑ſoning.

A SURFACE terminates a ſolid; a line terminates a ſurface; a point terminates a line; but I aſſert, that if the ideas of a point, line or ſurface were not indiviſible, 'tis im⯑poſſible we ſhou'd ever conceive theſe termi⯑nations. For let theſe ideas be ſuppos'd in⯑finitely diviſible; and then let the fancy en⯑deavour to fix itſelf on the idea of the laſt ſurface, line or point; it immediately finds this idea to break into parts; and upon its ſeizing the laſt of theſe parts, it loſes its hold by a new diviſion, and ſo on in infinitum, without any poſſibility of its arriving at a concluding idea. The number of fractions bring it no nearer the laſt diviſion, than the firſt idea it form'd. Every particle eludes the graſp by a new fraction; like quick⯑ſilver, when we endeavour to ſeize it. But as in fact there muſt be ſomething, which terminates the idea of every finite quantity; and as this terminating idea cannot itſelf conſiſt of parts or inferior ideas; otherwiſe it wou'd be the laſt of its parts, which fi⯑niſh'd the idea, and ſo on; this is a clear [84] proof, that the ideas of ſurfaces, lines and points admit not of any diviſion; thoſe of ſurfaces in depth; of lines in breadth and depth; and of points in any dimenſion.

THE ſchoolmen were ſo ſenſible of the force of this argument, that ſome of them maintain'd, that nature has mix'd among thoſe particles of matter, which are diviſible in infinitum, a number of mathematical points, in order to give a termination to bodies; and others eluded the force of this reaſon⯑ing by a heap of unintelligible cavils and diſtinctions. Both theſe adverſaries equally yield the victory. A man who hides him⯑ſelf, confeſſes as evidently the ſuperiority of his enemy, as another, who fairly delivers his arms.

THUS it appears, that the definitions of mathematics deſtroy the pretended demon⯑ſtrations; and that if we have the idea of indiviſible points, lines and ſurfaces conform⯑able to the definition, their exiſtence is cer⯑tainly poſſible: but if we have no ſuch idea, 'tis impoſſible we can ever conceive the ter⯑mination of any figure; without which con⯑ception there can be no geometrical demon⯑ſtration.

BUT I go farther, and maintain, that none of theſe demonſtrations can have ſuffi⯑cient [85] weight to eſtabliſh ſuch a principle, as this of infinite diviſibility; and that becauſe with regard to ſuch minute objects, they are not properly demonſtrations, being built on ideas, which are not exact, and maxims, which are not exact, and maxims, which are not preciſely true. When geo⯑metry decides any thing concerning the pro⯑portions of quantity, we ought not to look for the utmoſt preciſion and exactneſs. None of its proofs extend ſo far. It takes the di⯑menſions and proportions of figures juſtly; but roughly, and with ſome liberty. Its errors are never conſiderable; nor wou'd it err at all, did it not aſpire to ſuch an abſolute perfection.

I FIRST aſk mathematicians, what they mean when they ſay one line or ſurface is EQUAL to, or GREATER, or LESS than another? Let any of them give an anſwer, to whatever ſect he belongs, and whether he maintains the compoſition of extenſion by indiviſible points, or by quantities divi⯑ſible in infinitum. This queſtion will em⯑barraſs both of them.

THERE are few or no mathematicians, who defend the hypotheſis of indiviſible points; and yet theſe have the readieſt and juſteſt anſwer to the preſent queſtion. They need only reply, that lines or ſurfaces are [86] equal, when the numbers of points in each are equal; and that as the proportion of the numbers varies, the proportion of the lines and ſurfaces is alſo vary'd. But tho' this anſwer be juſt, as well as obvious; yet I may affirm, that this ſtandard of equality is entirely uſeleſs, and that it ne⯑ver is from ſuch a compariſon we deter⯑mine objects to be equal or unequal with reſpect to each other. For as the points, which enter into the compoſition of any line or ſurface, whether perceiv'd by the ſight or touch, are ſo minute and ſo confounded with each other, that 'tis utterly impoſſible for the mind to compute their number, ſuch a computation will never afford us a ſtand⯑ard, by which we may judge of proportions. No one will ever be able to determine by an exact numeration, that an inch has fewer points than a foot, or a foot fewer than an ell or any greater meaſure; for which rea⯑ſon we ſeldom or never conſider this as the ſtandard of equality or inequality.

As to thoſe, who imagine, that exten⯑ſion is diviſible in infinitum, 'tis impoſſible they can make uſe of this anſwer, or fix the equality of any line or ſurface by a nume⯑ration of its component parts. For ſince, according to their hypotheſis, the leaſt as [87] well as greateſt figures contain an infinite number of parts; and ſince infinite num⯑bers, properly ſpeaking, can neither be equal nor unequal with reſpect to each other; the equality or inequality of any portions of ſpace can never depend on any proportion in the number of their parts. 'Tis true, it may be ſaid, that the inequality of an ell and a yard conſiſts in the different numbers of the feet, of which they are compos'd; and that of a foot and a yard in the number of the inches. But as that quantity we call an inch in the one is ſuppos'd equal to what we call an inch in the other, and as 'tis im⯑poſſible for the mind to find this equality by proceeding in infinitum with theſe refe⯑rences to inferior quantities; 'tis evident, that at laſt we muſt fix ſome ſtandard of equa⯑lity different from an enumeration of the parts.

THERE are ſome ^*, who pretend, that equality is beſt defin'd by congruity, and that any two figures are equal, when upon the placing of one upon the other, all their parts correſpond to and touch each other. In order to judge of this definition let us conſider, that ſince equality is a relation, it is not, ſtrictly ſpeaking, a property in the [88] figures themſelves, but ariſes merely from the compariſon, which the mind makes be⯑twixt them. If it conſiſts, therefore, in this imaginary application and mutual contact of parts, we muſt at leaſt have a diſtinct no⯑tion of theſe parts, and muſt conceive their contact. Now 'tis plain, that in this con⯑ception we wou'd run up theſe parts to the greateſt minuteneſs, which can poſſibly be conceiv'd; ſince the contact of large parts wou'd never render the figures equal. But the minuteſt parts we can conceive are ma⯑thematical points; and conſequently this ſtandard of equality is the ſame with that deriv'd from the equality of the number of points; which we have already determin'd to be a juſt but an uſeleſs ſtandard. We muſt therefore look to ſome other quarter for a ſolution of the preſent difficulty.

'TIS evident, that the eye, or rather the mind is often able at one view to determine the proportions of bodies, and pronounce them equal to, or greater or leſs than each other, without examining or comparing the number of their minute parts. Such judg⯑ments are not only common, but in many caſes certain and infallible. When the mea⯑ſure of a yard and that of a foot are preſented, the mind can no more queſtion, [89] that the firſt is longer than the ſecond, than it can doubt of thoſe principles, which are the moſt clear and ſelf-evident.

THERE are therefore three proportions, which the mind diſtinguiſhes in the general appearance of its objects, and calls by the names of greater, leſs and equal. But tho' its deciſions concerning theſe proportions be ſometimes infallible, they are not always ſo; nor are our judgments of this kind more ex⯑empt from doubt and error, than thoſe on any other ſubject. We frequently correct our firſt opinion by a review and reflection; and pronounce thoſe objects to be equal, which at firſt we eſteem'd unequal; and re⯑gard an object as leſs, tho' before it appear'd greater than another. Nor is this the only correction, which theſe judgments of our ſenſes undergo; but we often diſcover our error by a juxta-poſition of the objects; or where that is impracticable, by the uſe of ſome common and invariable meaſure, which being ſucceſſively apply'd to each, informs us of their different proportions. And even this correction is ſuſceptible of a new cor⯑rection, and of different degrees of exactneſs, according to the nature of the inſtrument, by which we meaſure the bodies, and the care which we employ in the compariſon.

[90] WHEN therefore the mind is accuſtom'd to theſe judgments and their corrections, and finds that the ſame proportion which makes two figures have in the eye that ap⯑pearance, which we call equality, makes them alſo correſpond to each other, and to any common meaſure, with which they are compar'd, we form a mix'd notion of equa⯑lity deriv'd both from the looſer and ſtricter methods of compariſon. But we are not con⯑tent with this. For as ſound reaſon con⯑vinces us that there are bodies vaſtly more minute than thoſe, which appear to the ſen⯑ſes; and as a falſe reaſon wou'd perſwade us, that there are bodies infinitely more mi⯑nute; we clearly perceive, that we are not poſſeſs'd of any inſtrument or art of mea⯑ſuring, which can ſecure us from all error and uncertainty. We are ſenſible, that the addition or removal of one of theſe minute parts, is not diſcernible either in the appear⯑ance or meaſuring; and as we imagine, that two figures, which were equal before, can⯑not be equal after this removal or addition, we therefore ſuppoſe ſome imaginary ſtand⯑ard of equality, by which the appearances and meaſuring are exactly corrected, and the figures reduc'd entirely to that proportion. This ſtandard is plainly imaginary. For as [91] the very idea of equality is that of ſuch a particular appearance corrected by juxta-po⯑ſition or a common meaſure, the notion of any correction beyond what we have inſtru⯑ments and art to make, is a mere fiction of the mind, and uſeleſs as well as incompre⯑henſible. But tho' this ſtandard be only ima⯑ginary, the fiction however is very natural; nor is any thing more uſual, than for the mind to proceed after this manner with any action, even after the reaſon has ceas'd, which firſt determin'd it to begin. This appears very conſpicuouſly with regard to time; where tho' 'tis evident we have no exact method of determining the propor⯑tions of parts, not even ſo exact as in exten⯑ſion, yet the various corrections of our mea⯑ſures, and their different degrees of exactneſs, have given us an obſcure and implicit no⯑tion of a perfect and entire equality. The caſe is the ſame in many other ſubjects. A muſician finding his ear become every day more delicate, and correcting himſelf by re⯑flection and attention, proceeds with the ſame act of the mind, even when the ſubject fails him, and entertains a notion of a com⯑pleat tierce or octave, without being able to tell whence he derives his ſtandard. A painter forms the ſame fiction with regard [92] to colours. A mechanic with regard to motion. To the one light and ſhade; to the other ſwift and ſlow are imagin'd to be capable of an exact compariſon and equality beyond the judgments of the ſenſes.

WE MAY apply the ſame reaſoning to CURVE and RIGHT lines. Nothing is more apparent to the ſenſes, than the diſtinction betwixt a curve and a right line; nor are there any ideas we more eaſily form than the ideas of theſe objects. But however eaſily we may form theſe ideas, 'tis impoſſible to produce any definition of them, which will fix the preciſe boundaries betwixt them. When we draw lines upon paper or any continu'd ſurface, there is a certain order, by which the lines run along from one point to ano⯑ther, that they may produce the entire im⯑preſſion of a curve or right line; but this order is perfectly unknown, and nothing is obſerv'd but the united appearance. Thus even upon the ſyſtem of indiviſible points, we can only form a diſtant notion of ſome unknown ſtandard to theſe objects. Upon that of infinite diviſibility we cannot go even this length; but are reduc'd meerly to the general appearance, as the rule by which we determine lines to be either curve or right ones. But tho' we can give no perfect de⯑finition [93] of theſe lines, nor produce any very exact method of diſtinguiſhing the one from the other; yet this hinders us not from correcting the firſt appearance by a more ac⯑curate conſideration, and by a compariſon with ſome rule, of whoſe rectitude from re⯑peated trials we have a greater aſſurance. And 'tis from theſe corrections, and by car⯑rying on the ſame action of the mind, even when its reaſon fails us, that we form the looſe idea of a perfect ſtandard to theſe fi⯑gures, without being able to explain or com⯑prehend it.

'TIS true, mathematicians pretend they give an exact definition of a right line, when they ſay, it is the ſhorteſt way betwixt two points. But in the firſt place I obſerve, that this is more properly the diſcovery of one of the properties of a right line, than a juſt definition of it. For I aſk any one, if upon mention of a right line he thinks not imme⯑diately on ſuch a particular appearance, and if 'tis not by accident only that he conſiders this property? A right line can be compre⯑hended alone; but this definition is unintel⯑ligible without a compariſon with other lines, which we conceive to be more extended. In common life 'tis eſtabliſh'd as a maxim, that the ſtreighteſt way is always the ſhort⯑eſt; [94] which wou'd be as abſurd as to ſay, the ſhorteſt way is always the ſhorteſt, if our idea of a right line was not different from that of the ſhorteſt way betwixt two points.

SECONDLY, I repeat what I have already eſtabliſh'd, that we have no preciſe idea of equality and inequality, ſhorter and longer, more than of a right line or a curve; and conſequently that the one can never afford us a perfect ſtandard for the other. An ex⯑act idea can never be built on ſuch as are looſe and undeterminate.

THE idea of a plain ſurface is as little ſuſ⯑ceptible of a preciſe ſtandard as that of a right line; nor have we any other means of diſtinguiſhing ſuch a ſurface, than its ge⯑neral appearance. 'Tis in vain, that mathe⯑maticians repreſent a plain ſurface as pro⯑duc'd by the flowing of a right line. 'Twill immediately be objected, that our idea of a ſurface is as independent of this method of forming a ſurface, as our idea of an ellipſe is of that of a cone; that the idea of a right line is no more preciſe than that of a plain ſurface; that a right line may flow irregu⯑larly, and by that means form a figure quite different from a plane; and that therefore we muſt ſuppoſe it to flow along two right [95] lines, parallel to each other, and on the ſame plane; which is a deſcription, that explains a thing by itſelf, and returns in a circle.

IT appears, then, that the ideas which are moſt eſſential to geometry, viz. thoſe of equality and inequality, of a right line and a plain ſurface, are far from being exact and determinate, according to our common method of conceiving them. Not only we are incapable of telling, if the caſe be in any degree doubtful, when ſuch particular figures are equal; when ſuch a line is a right one, and ſuch a ſurface a plain one; but we can form no idea of that proportion, or of theſe figures, which is firm and inva⯑riable. Our appeal is ſtill to the weak and fallible judgment, which we make from the appearance of the objects, and correct by a compaſs or common meaſure; and if we join the ſuppoſition of any farther correction, 'tis of ſuch-a-one as is either uſeleſs or ima⯑ginary. In vain ſhou'd we have recourſe to the common topic, and employ the ſuppo⯑ſition of a deity, whoſe omnipotence may enable him to form a perfect geometrical figure, and deſcribe a right line without any curve or inflexion. As the ultimate ſtand⯑ard of theſe figures is deriv'd from nothing but the ſenſes and imagination, 'tis abſurd to [96] talk of any perfection beyond what theſe faculties can judge of; ſince the true per⯑fection of any thing conſiſts in its confor⯑mity to its ſtandard.

NOW ſince theſe ideas are ſo looſe and uncertain, I wou'd fain aſk any mathema⯑tician what infallible aſſurance he has, not only of the more intricate and obſcure pro⯑poſitions of his ſcience, but of the moſt vul⯑gar and obvious principles? How can he prove to me, for inſtance, that two right lines cannot have one common ſegment? Or that 'tis impoſſible to draw more than one right line betwixt any two points? Shou'd he tell me, that theſe opinions are obvi⯑ouſly abſurd, and repugnant to our clear ideas; I wou'd anſwer, that I do not deny, where two right lines incline upon each other with a ſenſible angle, but 'tis abſurd to imagine them to have a common ſegment. But ſuppoſing theſe two lines to approach at the rate of an inch in twenty leagues, I perceive no abſurdity in aſſerting, that upon their contact they become one. For, I be⯑ſeech you, by what rule or ſtandard do you judge, when you aſſert, that the line, in which I have ſuppos'd them to concur, can⯑not make the ſame right line with thoſe two, that form ſo ſmall an angle betwixt [97] them? You muſt ſurely have ſome idea of a right line, to which this line does not agree. Do you therefore mean, that it takes not the points in the ſame order and by the ſame rule, as is peculiar and eſſen⯑tial to a right line? If ſo, I muſt inform you, that beſides that in judging after this manner you allow, that extenſion is com⯑pos'd of indiviſible points (which, perhaps, is more than you intend) beſides this, I ſay, I muſt inform you, that neither is this the ſtandard from which we form the idea of a right line; nor, if it were, is there any ſuch firmneſs in our ſenſes or imagination, as to determine when ſuch an order is vio⯑lated or preſerv'd. The original ſtandard of a right line is in reality nothing but a cer⯑tain general appearance; and 'tis evident right lines may be made to concur with each other, and yet correſpond to this ſtan⯑dard, tho' corrected by all the means either practicable or imaginable.

THIS may open our eyes a little, and let us ſee, that no geometrical demonſtra⯑tion for the infinite diviſibility of extenſion can have ſo much force as what we natu⯑rally attribute to every argument, which is ſupported by ſuch magnificent pretenſions. At the ſame time we may learn the reaſon, [98] why geometry fails of evidence in this ſingle point, while all its other reaſonings com⯑mand our fulleſt aſſent and approbation. And indeed it ſeems more requiſite to give the reaſon of this exception, than to ſhew, that we really muſt make ſuch an exception, and regard all the mathematical arguments for infinite diviſibility as utterly ſophiſtical. For 'tis evident, that as no idea of quantity is infinitely diviſible, there cannot be ima⯑gin'd a more glaring abſurdity, than to en⯑deavour to prove, that quantity itſelf admits of ſuch a diviſion; and to prove this by means of ideas, which are directly oppoſite in that particular. And as this abſurdity is very glaring in itſelf, ſo there is no argument founded on it, which is not attended with a new abſurdity, and involves not an evident contradiction.

I MIGHT give as inſtances thoſe argu⯑ments for infinite diviſibility, which are de⯑riv'd from the point of contact. I know there is no mathematician, who will not refuſe to be judg'd by the diagrams he de⯑ſcribes upon paper, theſe being looſe draughts, as he will tell us, and ſerving only to con⯑vey with greater facility certain ideas, which are the true foundation of all our reaſoning. This I am ſatisfy'd with, and am willing to [99] reſt the controverſy merely upon theſe ideas. I deſire therefore our mathematician to form, as accurately as poſſible, the ideas of a circle and a right line; and I then aſk, if upon the conception of their contact he can con⯑ceive them as touching in a mathematical point, or if he muſt neceſſarily imagine them to concur for ſome ſpace. Which⯑ever ſide he chuſes, he runs himſelf into equal difficulties. If he affirms, that in tracing theſe figures in his imagination, he can imagine them to touch only in a point, he allows the poſſibility of that idea, and conſequently of the thing. If he ſays, that in his conception of the contact of thoſe lines he muſt make them concur, he thereby acknowledges the fallacy of geometrical de⯑monſtrations, when carry'd beyond a certain degree of minuteneſs; ſince 'tis certain he has ſuch demonſtrations againſt the concur⯑rence of a circle and a right line; that is, in other words, he can prove an idea, viz. that of concurrence, to be incompatible with two other ideas, viz, thoſe of a circle and right line; tho' at the ſame time he acknow⯑ledges theſe ideas to be inſeparable.

SECT. V. The ſame ſubject continu'd.

IF the ſecond part of my ſyſtem be true, that the idea of ſpace or extenſion is no⯑thing but the idea of viſible or tangible points diſtributed in a certain order; it follows, that we can form no idea of a vacuum, or ſpace, where there is nothing viſible or tangible. This gives riſe to three objections, which I ſhall examine together, becauſe the an⯑ſwer I ſhall give to one is a conſequence of that which I ſhall make uſe of for the others.

FIRST, It may be ſaid, that men have diſputed for many ages concerning a va⯑cuum and a plenum, without being able to bring the affair to a final deciſion; and philoſophers, even at this day, think them⯑ſelves at liberty to take party on either ſide, as their fancy leads them. But whatever foundation there may be for a controverſy concerning the things themſelves, it may be pretended, that the very diſpute is de⯑ciſive concerning the idea, and that 'tis im⯑poſſible men cou'd ſo long reaſon about a [101] vacuum, and either refute or defend it, with⯑out having a notion of what they refuted or defended.

SECONDLY, If this argument ſhou'd be conteſted, the reality or at leaſt poſſibility of the idea of a vacuum may be prov'd by the following reaſoning. Every idea is poſ⯑ſible, which is a neceſſary and infallible conſequence of ſuch as are poſſible. Now tho' we allow the world to be at preſent a plenum, we may eaſily conceive it to be de⯑priv'd of motion; and this idea will cer⯑tainly be allow'd poſſible. It muſt alſo be allow'd poſſible, to conceive the annihilation of any part of matter by the omnipotence of the deity, while the other parts remain at reſt. For as every idea, that is diſtin⯑guiſhable, is ſeparable by the imagination; and as every idea, that is ſeparable by the imagination, may be conceiv'd to be ſepa⯑rately exiſtent; 'tis evident, that the exi⯑ſtence of one particle of matter, no more implies the exiſtence of another, than a ſquare figure in one body implies a ſquare figure in every one. This being granted, I now demand what reſults from the concur⯑rence of theſe two poſſible ideas of reſt and annihilation, and what muſt we conceive to follow upon the annihilation of all the air [102] and ſubtile matter in the chamber, ſuppo⯑ſing the walls to remain the ſame, without any motion or alteration? There are ſome metaphyſicians, who anſwer, that ſince mat⯑ter and extenſion are the ſame, the annihi⯑lation of one neceſſarily implies that of the other; and there being now no diſtance be⯑twixt the walls of the chamber, they touch each other; in the ſame manner as my hand touches the paper, which is immediately before me. But tho' this anſwer be very common, I defy theſe metaphyſicians to con⯑ceive the matter according to their hypo⯑theſis, or imagine the floor and roof, with all the oppoſite ſides of the chamber, to touch each other, while they continue in reſt, and preſerve the ſame poſition. For how can the two walls, that run from ſouth to north, touch each other, while they touch the oppoſite ends of two walls, that run from eaſt to weſt? And how can the floor and roof ever meet, while they are ſeparated by the four walls, that lie in a contrary po⯑ſition? If you change their poſition, you ſuppoſe a motion. If you conceive any thing betwixt them, you ſuppoſe a new cre⯑ation. But keeping ſtrictly to the two ideas of reſt and annihilation, 'tis evident, that the idea, which reſults from them, is not that [103] of a contact of parts, but ſomething elſe; which is concluded to be the idea of a va⯑cuum.

THE third objection carries the matter ſtill farther, and not only aſſerts, that the idea of a vacuum is real and poſſible, but alſo neceſſary and unavoidable. This aſſer⯑tion is founded on the motion we obſerve in bodies, which, 'tis maintain'd, wou'd be impoſſible and inconceivable without a va⯑cuum, into which one body muſt move in order to make way for another. I ſhall not enlarge upon this objection, becauſe it prin⯑cipally belongs to natural philoſophy, which lies without our preſent ſphere.

IN order to anſwer theſe objections, we muſt take the matter pretty deep, and con⯑ſider the nature and origin of ſeveral ideas, leſt we diſpute without underſtanding per⯑fectly the ſubject of the controverſy. 'Tis evident the idea of darkneſs is no poſitive idea, but merely the negation of light, or more properly ſpeaking, of colour'd and vi⯑ſible objects. A man, who enjoys his ſight, receives no other perception from turning his eyes on every ſide, when entirely depriv'd of light, than what is common to him with one born blind; and 'tis certain ſuch-a-one has no idea either of light or darkneſs. The [104] conſequence of this is, that 'tis not from the mere removal of viſible objects we re⯑ceive the impreſſion of extenſion without matter; and that the idea of utter darkneſs can never be the ſame with that of va⯑cuum.

SUPPOSE again a man to be ſupported in the air, and to be ſoftly convey'd along by ſome inviſible power; 'tis evident he is ſenſible of nothing, and never receives the idea of extenſion, nor indeed any idea, from this invariable motion. Even ſuppoſing he moves his limbs to and fro, this cannot con⯑vey to him that idea. He feels in that caſe a certain ſenſation or impreſſion, the parts of which are ſucceſſive to each other, and may give him the idea of time: But cer⯑tainly are not diſpos'd in ſuch a manner, as is neceſſary to convey the idea of ſpace or extenſion.

SINCE then it appears, that darkneſs and motion, with the utter removal of every thing viſible and tangible, can never give us the idea of extenſion without matter, or of a vacuum; the next queſtion is, whether they can convey this idea, when mix'd with ſomething viſible and tangible?

'TIS commonly allow'd by philoſophers, that all bodies, which diſcover themſelves to [105] the eye, appear as if painted on a plain ſur⯑face, and that their different degrees of re⯑moteneſs from ourſelves are diſcover'd more by reaſon than by the ſenſes. When I hold up my hand before me, and ſpread my fin⯑gers, they are ſeparated as perfectly by the blue colour of the firmament, as they cou'd be by any viſible object, which I cou'd place betwixt them. In order, therefore, to know whether the ſight can convey the impreſſion and idea of a vacuum, we muſt ſuppoſe, that amidſt an entire darkneſs, there are luminous bodies preſented to us, whoſe light diſcovers only theſe bodies themſelves, without giving us any impreſſion of the ſurrounding objects.

WE muſt form a parallel ſuppoſition con⯑cerning the objects of our feeling. 'Tis not proper to ſuppoſe a perfect removal of all tangible objects: we muſt allow ſomething to be perceiv'd by the feeling; and after an interval and motion of the hand or other organ of ſenſation, another object of the touch to be met with; and upon leaving that, another; and ſo on, as often as we pleaſe. The queſtion is, whether theſe in⯑tervals do not afford us the idea of extenſion without body?

TO begin with the firſt caſe; 'tis evident, that when only two luminous bodies ap⯑pear [106] to the eye, we can perceive, whether they be conjoin'd or ſeparate; whether they be ſeparated by a great or ſmall diſtance; and if this diſtance varies, we can perceive its increaſe or diminution, with the motion of the bodies. But as the diſtance is not in this caſe any thing colour'd or viſible, it may be thought that there is here a vacuum or pure extenſion, not only intelligible to the mind, but obvious to the very ſenſes.

THIS is our natural and moſt familiar way of thinking; but which we ſhall learn to correct by a little reflection. We may obſerve, that when two bodies preſent them⯑ſelves, where there was formerly an entire darkneſs, the only change, that is diſcover⯑able, is in the appearance of theſe two ob⯑jects, and that all the reſt continues to be as before, a perfect negation of light, and of every colour'd or viſible object. This is not only true of what may be ſaid to be remote from theſe bodies, but alſo of the very diſtance; which is interpos'd betwixt them; that being nothing but darkneſs, or the negation of light; without parts, with⯑out compoſition, invariable and indiviſible. Now ſince this diſtance cauſes no percep⯑tion different from what a blind man receives from his eyes, or what is convey'd to us in [107] the darkeſt night, it muſt partake of the ſame properties: And as blindneſs and dark⯑neſs afford us no ideas of extenſion, 'tis im⯑poſſible that the dark and undiſtinguiſhable diſtance betwixt two bodies can ever pro⯑duce that idea.

THE ſole difference betwixt an abſolute darkneſs and the appearance of two or more viſible luminous objects conſiſts, as I ſaid, in the objects themſelves, and in the manner they affect our ſenſes. The angles, which the rays of light flowing from them, form with each other; the motion that is requir'd in the eye, in its paſſage from one to the other; and the different parts of the organs, which are affected by them; theſe produce the only perceptions, from which we can judge of the diſtance. But as theſe perceptions are each of them ſimple and indiviſible, they can never give us the idea of extenſion.

WE may illuſtrate this by conſidering the ſenſe of feeling, and the imaginary diſtance or interval interpos'd betwixt tangible or ſolid objects. I ſuppoſe two caſes, viz. that of a man ſupported in the air, and moving his limbs to and fro, without meeting any thing tangible; and that of a man, who feeling ſomething tangible, leaves it, and after a motion, of which he is ſenſible, perceives [108] another tangible object; and I then aſk, wherein conſiſts the difference betwixt theſe two caſes? No one will make any ſcruple to affirm, that it conſiſts meerly in the per⯑ceiving thoſe objects, and that the ſenſation, which ariſes from the motion, is in both caſes the ſame: And as that ſenſation is not capable of conveying to us an idea of extenſion, when unaccompany'd with ſome other perception, it can no more give us that idea, when mix'd with the impreſſions of tangible objects; ſince that mixture pro⯑duces no alteration upon it.

BUT tho' motion and darkneſs, either a⯑lone, or attended with tangible and viſible objects, convey no idea of a vacuum or ex⯑tenſion without matter, yet they are the cauſes why we falſly imagine we can form ſuch an idea. For there is a cloſe relation betwixt that motion and darkneſs, and a real extenſion, or compoſition of viſible and tangible objects.

FIRST, We may obſerve, that two vi⯑ſible objects appearing in the midſt of utter darkneſs, affect the ſenſes in the ſame man⯑ner, and form the ſame angle by the rays, which flow from them, and meet in the eye, as if the diſtance betwixt them were fill'd with viſible objects, that give us a true [109] idea of extenſion. The ſenſation of motion is likewiſe the ſame, when there is nothing tangible interpos'd betwixt two bodies, as when we feel a compounded body, whoſe different parts are plac'd beyond each other.

SECONDLY, We find by experience, that two bodies, which are ſo plac'd as to affect the ſenſes in the ſame manner with two others, that have a certain extent of viſible objects interpos'd betwixt them, are capable of receiving the ſame extent, with⯑out any ſenſible impulſe or penetration, and without any change on that angle, under which they appear to the ſenſes. In like manner, where there is one object, which we cannot feel after another without an in⯑terval, and the perceiving of that ſenſation we call motion in our hand or organ of ſen⯑ſation; experience ſhews us, that 'tis poſſi⯑ble the ſame object may be felt with the ſame ſenſation of motion, along with the interpos'd impreſſion of ſolid and tangible objects, attending the ſenſation. That is, in other words, an inviſible and intangible diſtance may be converted into a viſible and tangible one, without any change on the diſtant objects.

THIRDLY, We may obſerve, as another relation betwixt theſe two kinds of diſtance, [110] that they have nearly the ſame effects on every natural phaenomenon. For as all qualities, ſuch as heat, cold, light, attrac⯑tion, &c. diminiſh in proportion to the di⯑ſtance; there is but little difference obſerv'd, whether this diſtance be mark'd out by com⯑pounded and ſenſible objects, or be known only by the manner, in which the diſtant objects affect the ſenſes.

HERE then are three relations betwixt that diſtance, which conveys the idea of ex⯑tenſion, and that other, which is not fill'd with any colour'd or ſolid object. The di⯑ſtant objects affect the ſenſes in the ſame manner, whether ſeparated by the one diſtance or the other; the ſecond ſpecies of diſtance is found capable of receiving the firſt; and they both equally diminiſh the force of every quality.

THESE relations betwixt the two kinds of diſtance will afford us an eaſy reaſon, why the one has ſo often been taken for the other, and why we imagine we have an idea of extenſion without the idea of any object either of the ſight or feeling. For we may eſtabliſh it as a general maxim in this ſcience of human nature, that wherever there is a cloſe relation betwixt two ideas, the mind is very apt to miſtake them, and [111] in all its diſcourſes and reaſonings to uſe the one for the other. This phaenomenon oc⯑curs on ſo many occaſions, and is of ſuch conſequence, that I cannot forbear ſtopping a moment to examine its cauſes. I ſhall only premiſe, that we muſt diſtinguiſh ex⯑actly betwixt the phaenomenon itſelf, and the cauſes, which I ſhall aſſign for it; and muſt not imagine from any uncertainty in the latter, that the former is alſo uncertain. The phaenomenon may be real, tho' my explication be chimerical. The falſhood of the one is no conſequence of that of the other; tho' at the ſame time we may ob⯑ſerve, that 'tis very natural for us to draw ſuch a conſequence; which is an evident inſtance of that very principle, which I en⯑deavour to explain.

WHEN I receiv'd the relations of reſemb⯑lance, contiguity and cauſation, as principles of union among ideas, without examining into their cauſes, 'twas more in proſecution of my firſt maxim, that we muſt in the end reſt contented with experience, than for want of ſomething ſpecious and plauſible, which I might have diſplay'd on that ſub⯑ject. 'Twou'd have been eaſy to have made an imaginary defection of the brain, and have ſhewn, why upon our conception of any [112] idea, the animal ſpirits run into all the con⯑tiguous traces, and rouze up the other ideas, that are related to it. But tho' I have ne⯑glected any advantage, which I might have drawn from this topic in explaining the re⯑lations of ideas, I am afraid I muſt here have recourſe to it, in order to account for the miſtakes that ariſe from theſe relations. I ſhall therefore obſerve, that as the mind is endow'd with a power of exciting any idea it pleaſes; whenever it diſpatches the ſpirits into that region of the brain, in which the idea is plac'd; theſe ſpirits always excite the idea, when they run preciſely into the proper traces, and rummage that cell, which belongs to the idea. But as their motion is ſeldom direct, and naturally turns a little to the one ſide or the other; for this reaſon the animal ſpirits, falling into the contigu⯑ous traces, preſent other related ideas in lieu of that, which the mind deſir'd at firſt to ſurvey. This change we are not always ſen⯑ſible of; but continuing ſtill the ſame train of thought, make uſe of the related idea, which is preſented to us, and employ it in our rea⯑ſoning, as if it were the ſame with what we demanded. This is the cauſe of many miſtakes and ſophiſms in philoſphy; as [113] will naturally be imagin'd, and as it wou'd be eaſy to ſhow, if there was occaſion.

OF the three relations above-mention'd that of reſemblance is the moſt fertile ſource of error; and indeed there are few miſtakes in reaſoning, which do not borrow largely from that origin. Reſembling ideas are not only related together, but the actions of the mind, which we employ in conſidering them, are ſo little different, that we are not able to diſtinguiſh them. This laſt circumſtance is of great conſequence; and we may in ge⯑neral obſerve, that wherever the actions of the mind in forming any two ideas are the ſame or reſembling, we are very apt to confound theſe ideas, and take the one for the other. Of this we ſhall ſee many in⯑ſtances in the progreſs of this treatiſe. But tho' reſemblance be the relation, which moſt readily produces a miſtake in ideas, yet the others of cauſation and contiguity may alſo concur in the ſame influence. We might produce the figures of poets and orators, as ſufficient proofs of this, were it as uſual, as it is reaſonable, in metaphyſical ſubjects to draw our arguments from that quarter. But leſt metaphyſicians ſhou'd eſteem this below their dignity, I ſhall borrow a proof from an obſervation, which may be made on moſt [114] of their own diſcourſes, viz. that 'tis uſual for men to uſe words for ideas, and to talk inſtead of thinking in their reaſonings. We uſe words for ideas, becauſe they are com⯑monly ſo cloſely connected, that the mind eaſily miſtakes them. And this likewiſe is the reaſon, why we ſabſtitute the idea of a diſtance, which is not conſider'd either as viſible or tangible, in the room of extenſion, which is nothing but a compoſition of vi⯑ſible or tangible points diſpos'd in a certain order. In cauſing this miſtake there concur both the relations of cauſation and reſem⯑blance. As, the firſt ſpecies of diſtance is found to be convertible into the ſecond, 'tis in this reſpect a kind of cauſe; and the ſimilarity of their manner of affecting the ſenſes, and diminiſhing every quality, forms the relation of reſemblance.

AFTER this chain of reaſoning and ex⯑plication of my principles, I am now pre⯑par'd to anſwer all the objections that have been offer'd, whether deriv'd from metaphyſics or mechanics. The frequent diſputes con⯑cerning a vacuum, or extenſion without matter, prove not the reality of the idea, upon which the diſpute turns; there being nothing more common, than to ſee men de⯑ceive themſelves in this particular; eſpecially [115] when by means of any cloſe relation, there is another idea preſented, which may be the occaſion of their miſtake.

WE may make almoſt the ſame anſwer to the ſecond objection, deriv'd from the con⯑junction of the ideas of reſt and annihilation. When every thing is annihilated in the chamber, and the walls continue imove⯑able, the chamber muſt be conceiv'd much in the ſame manner as at preſent, when the air that fills it, is not an object of the ſenſes. This annihilation leaves to the eye, that fictitious diſtance, which is diſcover'd by the different parts of the organ, that are affected, and by the degrees of light and ſhade; and to the feeling, that which con⯑ſiſts in a ſenſation of motion in the hand, or other member of the body. In vain ſhou'd we ſearch any farther. On which⯑ever ſide we turn this ſubject, we ſhall find that theſe are the only impreſſions ſuch an object can produce after the ſuppos'd annihi⯑lation; and it has already been remark'd, that impreſſions can give riſe to no ideas, but to ſuch as reſemble them.

SINCE a body interpos'd betwixt two others may be ſuppos'd to be annihi⯑lated, without producing any change upon ſuch as lie on each hand of it, 'tis eaſily [116] conceiv'd, how it may be created anew, and yet produce as little alteration. Now the motion of a body has much the ſame effect as its creation. The diſtant bodies are no more affected in the one caſe, than in the other. This ſuffices to ſatisfy the ima⯑gination, and proves there is no repugnance in ſuch a motion. Afterwards experience comes in play to perſuade us that two bo⯑dies, ſituated in the manner above-deſcrib'd, have really ſuch a capacity of receiving body betwixt them, and that there is no obſtacle to the converſion of the inviſible and intan⯑gible diſtance into one that is viſible and tangible. However natural that converſion may ſeem, we cannot be ſure it is practi⯑cable, before we have had experience of it.

THUS I ſeem to have anſwer'd the three objections above-mention'd; tho' at the ſame time I am ſenſible, that few will be ſatisfy'd with theſe anſwers, but will immediately propoſe new objections and difficulties. 'Twill probably be ſaid, that my reaſoning makes nothing to the matter in hand, and that I explain only the manner in which objects affect the ſenſes, without endeavouring to account for their real nature and operations. Tho' there be nothing viſible or tangible interpos'd betwixt two bodies, yet we find [117] by experience, that the bodies may be plac'd in the ſame manner, with regard to the eye, and require the ſame motion of the hand in paſſing from one to the other, as if di⯑vided by ſomething viſible and tangible. This inviſible and intangible diſtance is alſo found by experience to contain a capacity of receiv⯑ing body, or of becoming viſible and tan⯑gible. Here is the whole of my ſyſtem; and in no part of it have I endeavour'd to explain the cauſe, which ſeparates bodies after this manner, and gives them a capacity of receiving others betwixt them, without any impulſe or penetration.

I ANSWER this objection, by pleading guilty, and by confeſſing that my intention never was to penetrate into the nature of bo⯑dies, or explain the ſecret cauſes of their operations. For beſides that this belongs not to my preſent purpoſe, I am afraid, that ſuch an enterprize is beyond the reach of human underſtanding, and that we can never pretend to know body otherwiſe than by thoſe external properties, which diſcover themſelves to the ſenſes. As to thoſe who attempt any thing farther, I cannot approve of their ambition, till I ſee, in ſome one in⯑ſtance at leaſt, that they have met with ſucceſs. But at preſent I content myſelf [118] with knowing perfectly the manner in which objects affect my ſenſes, and their connections with each other, as far as experience informs me of them. This ſuffices for the conduct of life; and this alſo ſuffices for my phi⯑loſophy, which pretends only to explain the nature and cauſes of our perceptions, or im⯑preſſions and ideas. [...].

I SHALL conclude this ſubject of exten⯑ſion with a paradox, which will eaſily be explain'd from the foregoing reaſoning. This paradox is, that if you are pleas'd to give to the inviſible and intangible diſtance, or in other words, to the capacity of becoming a viſible and tangible diſtance, the name of a vacuum, extenſion and matter are the ſame, and yet there is a vacuum. If you will not give it that name, motion is poſſible in a plenum, without any impulſe in infinitum, without returning in a circle, and without penetration. But however we may expreſs ourſelves, we muſt always confeſs, that we have no idea of any real extenſion without filling it with ſenſible objects, and conceiving its parts as viſible or tangible.

AS to the doctrine, that time is nothing but the manner, in which ſome real objects exiſt; we may obſerve, that 'tis liable to the ſame objections as the ſimilar doctrine [119] with regard to extenſion. If it be a ſuffi⯑cient proof, that we have the idea of a va⯑cuum, becauſe we diſpute and reaſon con⯑cerning it; we muſt for the ſame reaſon have the idea of time without any change⯑able exiſtence; ſince there is no ſubject of diſpute more frequent and common. But that we really have no ſuch idea, is certain. For whence ſhou'd it be deriv'd? Does it ariſe from an impreſſion of ſenſation or of reflection? Point it out diſtinctly to us, that we may know its nature and qualities. But if you cannot point out any ſuch impreſſion, you may be certain you are miſtaken, when you imagine you have any ſuch idea.

BUT tho' it be impoſſible to ſhew the impreſſion, from which the idea of time without a changeable exiſtence is deriv'd; yet we can eaſily point out thoſe appear⯑ances, which make us fancy we have that idea. For we may obſerve, that there is a continual ſucceſſion of perceptions in our mind; ſo that the idea of time being for ever preſent with us; when we conſider a ſtedfaſt object at five-a-clock, and regard the ſame at ſix; we are apt to apply to it that idea in the ſame manner as if every moment were diſtinguiſh'd by a dif⯑ferent poſition, or an alteration of the object. [120] The firſt and ſecond appearances of the ob⯑ject, being compar'd with the ſucceſſion of our perceptions, ſeem equally remov'd as if the object had really chang'd. To which we may add, what experience ſhews us, that the object was ſuſceptible of ſuch a number of changes betwixt theſe appearances; as alſo that the unchangeable or rather fictitious du⯑ration has the ſame effect upon every quality, by encreaſing or diminiſhing it, as that ſuc⯑ceſſion, which is obvious to the ſenſes. From theſe three relations we are apt to confound our ideas, and imagine we can form the idea of a time and duration, without any change or ſucceſſion.

SECT. VI. Of the idea of exiſtence, and of ex⯑ternal exiſtence.

IT may not be amiſs, before we leave this ſubject, to explain the ideas of exiſtence and of external exiſtence; which have their difficulties, as well as the ideas of ſpace and time. By this means we ſhall be the better prepar'd for the examination of knowledge and probability, when we underſtand per⯑fectly [121] all thoſe particular ideas, which may enter into our reaſoning.

THERE is no impreſſion nor idea of any kind, of which we have any conſciouſneſs or memory, that is not conceiv'd as exiſtent; and 'tis evident, that from this conſciouſ⯑neſs the moſt perfect idea and aſſurance of being is deriv'd. From hence we may form a dilemma, the moſt clear and concluſive that can be imagin'd, viz. that ſince we never remember any idea or impreſſion without attributing exiſtence to it, the idea of exi⯑ſtence muſt either be deriv'd from a diſtinct impreſſion, conjoin'd with every perception or object of our thought, or muſt be the very ſame with the idea of the perception or object.

As this dilemma is an evident conſequence of the principle, that every idea ariſes from a ſimilar impreſſion, ſo our deciſion betwixt the propoſitions of the dilemma is no more doubtful. So far from there being any di⯑ſtinct impreſſion, attending every impreſſion and every idea, that I do not think there are any two diſtinct impreſſions, which are inſeparably conjoin'd. Tho' certain ſenſa⯑tions may at one time be united, we quickly find they admit of a ſeparation, and may be preſented apart. And thus, tho' every im⯑preſſion [122] and idea we remember be conſi⯑der'd as exiſtent, the idea of exiſtence is not deriv'd from any particular impreſſion.

THE idea of exiſtence, then, is the very ſame with the idea of what we conceive to be exiſtent. To reflect on any thing ſimply, and to reflect on it as exiſtent, are nothing different from each other. That idea, when conjoin'd with the idea of any object, makes no addition to it. Whatever we conceive, we conceive to be exiſtent. Any idea we pleaſe to form is the idea of a being; and the idea of a being is any idea we pleaſe to form.

WHOEVER oppoſes this, muſt neceſſari⯑ly point out that diſtinct impreſſion, from which the idea of entity is deriv'd, and muſt prove, that this impreſſion is inſeparable from every perception we believe to be exiſtent. This we may without heſitation conclude to be impoſſible.

OUR foregoing ^* reaſoning concerning the diſtinction of ideas without any real diffe⯑rence will not here ſerve us in any ſtead. That kind of diſtinction is founded on the different reſemblances, which the ſame ſimple idea may have to ſeveral different ideas. But no object can be preſented reſembling ſome [123] object with reſpect to its exiſtence, and dif⯑ferent from others in the ſame particular; ſince every object, that is preſented, muſt neceſſarily be exiſtent.

A LIKE reaſoning will account for the idea of external exiſtence. We may obſerve, that 'tis univerſally allow'd by philoſophers, and is beſides pretty obvious of itſelf, that nothing is ever really preſent with the mind but its perceptions or impreſſions and ideas, and that external objects become known to us only by thoſe perceptions they occaſion. To hate, to love, to think, to feel, to ſee; all this is nothing but to perceive.

NOW ſince nothing is ever preſent to the mind but perceptions, and ſince all ideas are deriv'd from ſomething antecedently preſent to the mind; it follows, that 'tis impoſſible for us ſo much as to conceive or form an idea of any thing ſpecifically different from ideas and impreſſions. Let us fix our at⯑tention out of ourſelves as much as poſſible: Let us chace our imagination to the hea⯑vens, or to the utmoſt limits of the univerſe; we never really advance a ſtep beyond our⯑ſelves, nor can conceive any kind of exi⯑ſtence, but thoſe perceptions, which have appear'd in that narrow compaſs. This is [124] the univerſe of the imagination, nor have we any idea but what is there produc'd.

THE fartheſt we can go towards a con⯑ception of external objects, when ſuppos'd ſpecifically different from our perceptions, is to form a relative idea of them, without pretending to comprehend the related ob⯑jects. Generally ſpeaking we do not ſuppoſe them ſpecifically different; but only attri⯑bute to them different relations, connections and durations. But of this more fully here⯑after ^*.

SECT. I. Of knowledge.

THERE are ^* ſeven different kinds of philoſophical relation, viz. re⯑ſemblance, identity, relations of time and place, proportion in quantity or number, degrees in any quality, contrariety, and cauſation. Theſe relations may be divided into two claſſes; into ſuch as depend entirely on the ideas, which we compare together, and ſuch as may be chang'd without any change in the ideas. 'Tis from the idea of a triangle, that we diſcover the relation of equality, which its three angles bear to two right ones; and this relation is invariable, as long as our idea remains the ſame. On the contrary, [126] the relations of contiguity and diſtance be⯑twixt two objects may be chang'd merely by an alteration of their place, without any change on the objects themſelves or on their ideas; and the place it depends on a hun⯑dred different accidents, which cannot be foreſeen by the mind. 'Tis the ſame caſe with identity and cauſation. Two objects, tho' perfectly reſembling each other, and even appearing in the ſame place at diffe⯑rent times, may be numerically different: And as the power, by which one object pro⯑duces another, is never diſcoverable merely from their idea, 'tis evident cauſe and effect are relations, of which we receive infor⯑mation from experience, and not from any abſtract reaſoning or reflection. There is no ſingle phaenomenon, even the moſt ſimple, which can be accounted for from the qua⯑lities of the objects, as they appear to us; or which we cou'd foreſee without the help of our memory and experience.

IT appears, therefore, that of theſe ſeven philoſophical relations, there remain only four, which depending ſolely upon ideas, can be the objects of knowledge and cer⯑tainty. Theſe four are reſemblance, contra⯑riety, degrees in quality, and proportions in quantity or number. Three of theſe rela⯑tions [127] are diſcoverable at firſt ſight, and fall more properly under the province of intui⯑tion than demonſtration. When any ob⯑jects reſemble each other, the reſemblance will at firſt ſtrike the eye, or rather the mind; and ſeldom requires a ſecond exa⯑mination. The caſe is the ſame with con⯑trariety, and with the degrees of any quality. No one can once doubt but exiſtence and non-exiſtence deſtroy each other, and are perfectly incompatible and contrary. And tho' it be impoſſible to judge exactly of the degrees of any quality, ſuch as colour, taſte, heat, cold, when the difference betwixt them is very ſmall; yet 'tis eaſy to decide, that any of them is ſuperior or inferior to another, when their difference is conſider⯑able. And this deciſion we always pro⯑nounce at firſt ſight, without any enquiry or reaſoning.

WE might proceed, after the ſame man⯑ner, in fixing the proportions of quantity or number, and might at one view obſerve a ſuperiority or inferiority betwixt any num⯑bers, or figures; eſpecially where the dif⯑ference is very great and remarkable. As to equality or any exact proportion, we can only gueſs at it from a ſingle conſideration; except in very ſhort numbers, or very limited [128] portions of extenſion; which are comprehend⯑ed in an inſtant, and where we perceive an impoſſibility of falling into any conſiderable error. In all other caſes we muſt ſettle the proportions with ſome liberty, or proceed in a more artificial manner.

I HAVE already obſerv'd, that geometry, or the art, by which we fix the proportions of figures; tho' it much excels both in uni⯑verſality and exactneſs, the looſe judgments of the ſenſes and imagination; yet never at⯑tains a perfect preciſion and exactneſs. It's firſt principles are ſtill drawn from the general appearance of the objects; and that appear⯑ance can never afford us any ſecurity, when we examine the prodigious minuteneſs of which nature is ſuſceptible. Our ideas ſeem to give a perfect aſſurance, that no two right lines can have a common ſegment; but if we conſider theſe ideas, we ſhall find, that they always ſuppoſe a ſenſible inclination of the two lines, and that where the angle they form is extremely ſmall, we have no ſtand⯑ard of a right line ſo preciſe as to aſſure us of the truth of this propoſition. 'Tis the ſame caſe with moſt of the primary deciſions of the mathematics.

THERE remain, therefore, algebra and arithmetic as the only ſciences, in which we [129] can carry on a chain of reaſoning to any de⯑gree of intricacy, and yet preſerve a perfect exactneſs and certainty. We are poſſeſt of a preciſe ſtandard, by which we can judge of the equality and proportion of numbers; and according as they correſpond or not to that ſtandard, we determine their relations, without any poſſibility of error. When two numbers are ſo combin'd, as that the one has always an unite anſwering to every unite of the other, we pronounce them equal; and 'tis for want of ſuch a ſtandard of equa⯑lity in extenſion, that geometry can ſcarce be eſteem'd a perfect and infallible ſci⯑ence.

BUT here it may not be amiſs to obviate a difficulty, which may ariſe from my aſſert⯑ing, that tho' geometry falls ſhort of that perfect preciſion and certainty, which are peculiar to arithmetic and algebra, yet it excels the imperfect judgments of our ſenſes and imagination. The reaſon why I impute any defect to geometry, is, becauſe its ori⯑ginal and fundamantal principles are deriv'd merely from appearances; and it may per⯑haps be imagin'd, that this defect muſt always attend it, and keep it from ever reaching a greater exactneſs in the compariſon of ob⯑jects or ideas, than what our eye or imagi⯑nation [130] alone is able to attain. I own that this defect ſo far attends it, as to keep it from ever aſpiring to a full certainty: But ſince theſe fundamental principles depend on the eaſieſt and leaſt deceitful appearances, they beſtow on their conſequences a degree of exactneſs, of which theſe conſequences are ſingly incapable. 'Tis impoſſible for the eye to determine the angles of a chiliagon to be equal to 1996 right angles, or make any conjecture, that approaches this proportion; but when it determines, that right lines cannot concur; that we cannot draw more than one right line between two given points; it's miſtakes can never be of any conſe⯑quence. And this is the nature and uſe of geometry, to run us up to ſuch appearances, as, by reaſon of their ſimplicity, cannot lead us into any conſiderable error.

I SHALL here take occaſion to propoſe a ſecond obſervation concerning our demonſtra⯑tive reaſonings, which is ſuggeſted by the ſame ſubject of the mathematics. 'Tis uſual with mathematicians, to pretend, that thoſe ideas, which are their objects, are of ſo refin'd and ſpiritual a nature, that they fall not under the conception of the fancy, but muſt be comprehended by a pure and intellectual view, of which the ſuperior faculties of the ſoul [131] are alone capable. The ſame notion runs thro' moſt parts of philoſophy, and is prin⯑cipally made uſe of to explain our abſtract ideas, and to ſhew how we can form an idea of a triangle, for inſtance, which ſhall neither be an iſoceles nor ſcalenum, nor be confin'd to any particular length and pro⯑portion of ſides. 'Tis eaſy to ſee, why phi⯑loſophers are ſo fond of this notion of ſome ſpiritual and refin'd perceptions; ſince by that means they cover many of their abſurdities, and may refuſe to ſubmit to the deciſions of clear ideas, by appealing to ſuch as are ob⯑ſcure and uncertain. But to deſtroy this artifice, we need but reflect on that princi⯑ple ſo oft inſiſted on, that all our ideas are copy'd from our impreſſions. For from thence we may immediately conclude, that ſince all impreſſions are clear and preciſe, the ideas, which are copy'd from them, muſt be of the ſame nature, and can never, but from our fault, contain any thing ſo dark and intricate. An idea is by its very na⯑ture weaker and fainter than an impreſſion; but being in every other reſpect the ſame, cannot imply any very great myſtery. If its weakneſs render it obſcure, 'tis our buſi⯑neſs to remedy that defect, as much as poſſible, by keeping the idea ſteady and [132] preciſe; and till we have done ſo, 'tis in vain to pretend to reaſoning and philoſo⯑phy.

SECT. II. Of probability; and of the idea of cauſe and effect.

THIS is all I think neceſſary to ob⯑ſerve concerning thoſe four relations, which are the foundation of ſcience; but as to the other three, which depend not upon the idea, and may be abſent or preſent even while that remains the ſame, 'twill be pro⯑per to explain them more particularly. Theſe three relations are identity, the ſitu⯑ations in time and place, and cauſation.

ALL kinds of reaſoning conſiſt in nothing but a compariſon, and a diſcovery of thoſe re⯑lations, either conſtant or inconſtant, which two or more objects bear to each other. This compariſon we may make, either when both the objects are preſent to the ſenſes, or when neither of them is preſent, or when only one. When both the objects are preſent to the ſenſes along with the relation, we call this perception rather than reaſoning; nor is there in this caſe any exerciſe of the [133] thought, or any action, properly ſpeaking, but a mere paſſive admiſſion of the impreſ⯑ſions thro' the organs of ſenſation. Accord⯑ing to this way of thinking, we ought not to receive as reaſoning any of the obſervations we may make concerning identity, and the relations of time and place; ſince in none of them the mind can go beyond what is immediately preſent to the ſenſes, either to diſcover the real exiſtence or the relations of objects. 'Tis only cauſation, which produces ſuch a connexion, as to give us aſſurance from the exiſtence or action of one object, that 'twas follow'd or preceded by any other exiſtence or action; nor can the other two relations be ever made uſe of in reaſoning, except ſo far as they either affect or are affected by it. There is nothing in any ob⯑jects to perſwade us, that they are either al⯑ways remote or always contiguous; and when from experience and obſervation we diſco⯑ver, that their relation in this particular is invariable, we always conclude there is ſome ſecret cauſe, which ſeparates or unites them. The ſame reaſoning extends to identity. We readily ſuppoſe an object may continue in⯑dividually the ſame, tho' ſeveral times ab⯑ſent from and preſent to the ſenſes; and aſcribe to it an identity, notwithſtanding [134] the interruption of the perception, whenever we conclude, that if we had kept our eye or hand conſtantly upon it, it wou'd have convey'd an invariable and uninterrupted per⯑ception. But this concluſion beyond the impreſſions of our ſenſes can be founded only on the connexion of cauſe and effect; nor can we otherwiſe have any ſecurity, that the object is not chang'd upon us, how⯑ever much the new object may reſemble that which was formerly preſent to the ſen⯑ſes. Whenever we diſcover ſuch a perfect reſemblance, we conſider, whether it be common in that ſpecies of objects; whether poſſibly or probably any cauſe cou'd operate in producing the change and reſemblance; and according as we determine concerning theſe cauſes and effects, we form our judg⯑ment concerning the identity of the object.

HERE then it appears, that of thoſe three relations, which depend not upon the mere ideas, the only one, that can be trac'd beyond our ſenſes, and informs us of exiſ⯑tences and objects, which we do not ſee or feel, is cauſation. This relation, therefore, we ſhall endavour to explain fully before we leave the ſubject of the underſtanding.

TO BEGIN regularly, we muſt conſider the idea of cauſation, and ſee from what [135] origin it is deriv'd. 'Tis impoſſible to reaſon juſtly, without underſtanding per⯑fectly the idea concerning which we rea⯑ſon; and 'tis impoſſible perfectly to un⯑derſtand any idea, without tracing it up to its origin, and examining that primary im⯑preſſion, from which it ariſes. The exa⯑mination of the impreſſion beſtows a clear⯑neſs on the idea; and the examination of the idea beſtows a like clearneſs on all our reaſoning.

LET us therefore caſt our eye on any two objects, which we call cauſe and effect, and turn them on all ſides, in order to find that impreſſion, which produces an idea of ſuch prodigious conſequence. At firſt ſight I perceive, that I muſt not ſearch for it in any of the particular qualities of the objects; ſince, which-ever of theſe qualities I pitch on, I find ſome object, that is not poſſeſt of it, and yet falls under the denomination of cauſe or effect. And indeed there is no⯑thing exiſtent, either externally or internally, which is not to be conſider'd either as a cauſe or an effect; tho' 'tis plain there is no one quality, which univerſally belongs to all beings, and gives them a title to that de⯑nomination.

[136] THE idea, then, of cauſation muſt be deriv'd from ſome relation among objects; and that relation we muſt now endeavour to diſcover. I find in the firſt place, that whatever objects are conſider'd as cauſes or effects, are contiguous; and that nothing can operate in a time or place, which is ever ſo little remov'd from thoſe of its exiſtence. Tho' diſtant objects may ſometimes ſeem productive of each other, they are com⯑monly found upon examination to be link'd by a chain of cauſes, which are contiguous among themſelves, and to the diſtant ob⯑jects; and when in any particular inſtance we cannot diſcover this connexion, we ſtill preſume it to exiſt. We may therefore con⯑ſider the relation of CONTIGUITY as eſſen⯑tial to that of cauſation; at leaſt may ſup⯑poſe it ſuch, according to the general opi⯑nion, till we can find a more ^* proper oc⯑caſion to clear up this matter, by examin⯑ing what objects are or are not ſuſceptible of juxta-poſition and conjunction.

THE ſecond relation I ſhall obſerve as eſ⯑ſential to cauſes and effects, is not ſo uni⯑verſally acknowledg'd, but is liable to ſome controverſy. 'Tis that of PRIORITY of time in the cauſe before the effect. Some [137] pretend that 'tis not abſolutely neceſſary a cauſe ſhou'd precede its effect; but that any object or action, in the very firſt moment of its exiſtence, may exert its productive quality, and give riſe to another object or action, perfectly co-temporary with itſelf. But beſide that experience in moſt inſtances ſeems to contradict this opinion, we may eſtabliſh the relation of priority by a kind of inference or reaſoning. 'Tis an eſtab⯑liſh'd maxim both in natural and moral philoſophy, that an object, which exiſts for any time in its full perfection without pro⯑ducing another, is not its ſole cauſe; but is aſſiſted by ſome other principle, which puſhes it from its ſtate of inactivity, and makes it exert that energy, of which it was ſecretly poſſeſt. Now if any cauſe may be perfectly co-temporary with its effect, 'tis cer⯑tain, according to this maxim, that they muſt all of them be ſo; ſince any one of them, which retards its operation for a ſingle moment, exerts not itſelf at that very indi⯑vidual time, in which it might have ope⯑rated; and therefore is no proper cauſe. The conſequence of this wou'd be no leſs than the deſtruction of that ſucceſſion of cauſes, which we obſerve in the world; and indeed, the utter annihilation of time. For [138] if one cauſe were co-temporary with its effect, and this effect with its effect, and ſo on, 'tis plain there wou'd be no ſuch thing as ſucceſſion, and all objects muſt be co⯑exiſtent.

IF this argument appear ſatisfactory, 'tis well. If not, I beg the reader to allow me the ſame liberty, which I have us'd in the preceding caſe, of ſuppoſing it ſuch. For he ſhall find, that the affair is of no great importance.

HAVING thus diſcover'd or ſuppos'd the two relations of contiguity and ſucceſſion to be eſſential to cauſes and effects, I find I am ſtopt ſhort, and can proceed no farther in conſidering any ſingle inſtance of cauſe and effect. Motion in one body is regarded upon impulſe as the cauſe of motion in ano⯑ther. When we conſider theſe objects with the utmoſt attention, we find only that the one body approaches the other; and that the motion of it precedes that of the other, but without any ſenſible interval. 'Tis in vain to rack ourſelves with farther thought and reflection upon this ſubject. We can go no farther in conſidering this particular in⯑ſtance.

SHOU'D any one leave this inſtance, and pretend to define a cauſe, by ſaying it is [139] ſomething productive of another, 'tis evident he wou'd ſay nothing. For what does he mean by production? Can he give any defi⯑nition of it, that will not be the ſame with that of cauſation? If he can; I deſire it may be produc'd. If he cannot; he here runs in a circle, and gives a ſynonimous term in⯑ſtead of a definition.

SHALL we then reſt contented with theſe two relations of contiguity and ſucceſſion, as affording a compleat idea of cauſation? By no means. An object may be contiguous and prior to another, without being conſi⯑der'd as its cauſe. There is a NECESSARY CONNEXION to be taken into conſideration; and that relation is of much greater im⯑portance, than any of the other two above⯑mention'd.

HERE again I turn the object on all ſides, in order to diſcover the nature of this neceſſary connexion, and find the impreſſion, or impreſſions, from which its idea may be deriv'd. When I caſt my eye on the known qualities of objects, I immediately diſcover that the relation of cauſe and effect depends not in the leaſt on them. When I conſider their relations, I can find none but thoſe of contiguity and ſucceſſion; which I have al⯑ready regarded as imperfect and unſatiſ⯑factory. [140] Shall the deſpair of ſucceſs make me aſſert, that I am here poſſeſt of an idea, which is not preceded by any ſimilar im⯑preſſion? This wou'd be too ſtrong a proof of levity and inconſtancy; ſince the con⯑trary principle has been already ſo firmly eſtabliſh'd, as to admit of no farther doubt; at leaſt, till we have more fully examin'd the preſent difficulty.

WE muſt, therefore, proceed like thoſe, who being in ſearch of any thing, that lies conceal'd from them, and not finding it in the place they expected, beat about all the neighbouring fields, without any certain view or deſign, in hopes their good fortune will at laſt guide them to what they ſearch for. 'Tis neceſſary for us to leave the direct ſur⯑vey of this queſtion concerning the nature of that neceſſary connexion, which enters into our idea of cauſe and effect; and endeavour to find ſome other queſtions, the exami⯑nation of which will perhaps afford a hint, that may ſerve to clear up the preſent diffi⯑culty. Of theſe queſtions there occur two, which I ſhall proceed to examine, viz.

FIRST, For what reaſon we pronounce it neceſſary, that every thing whoſe exi⯑ſtence has a beginning, ſhou'd alſo have a cauſe?

[141] SECONDLY, Why we conclude, that ſuch particular cauſes muſt neceſſarily have ſuch particular effects; and what is the na⯑ture of that inference we draw from the one to the other, and of the belief we re⯑poſe in it?

I SHALL only obſerve before I proceed any farther, that tho' the ideas of cauſe and effect be deriv'd from the impreſſions of re⯑flection as well as from thoſe of ſenſation, yet for brevity's ſake, I commonly mention only the latter as the origin of theſe ideas; tho' I deſire that whatever I ſay of them may alſo extend to the former. Paſſions are con⯑nected with their objects and with one ano⯑ther; no leſs than external bodies are con⯑nected together. The ſame relation, then, of cauſe and effect, which belongs to one, muſt be common to all of them.

SECT. III. Why a cauſe is always neceſſary.

To begin with the firſt queſtion con⯑cerning the neceſſity of a cauſe: 'Tis a general maxim in philoſophy, that what⯑ever begins to exiſt, muſt have a cauſe of exiſ⯑tence. This is commonly taken for granted [143] in all reaſonings, without any proof given or demanded. 'Tis ſuppos'd to be founded on intuition, and to be one of thoſe max⯑ims, which tho' they may be deny'd with the lips, 'tis impoſſible for men in their hearts really to doubt of. But if we ex⯑amine this maxim by the idea of knowledge above-explain'd, we ſhall diſcover in it no mark of any ſuch intuitive certainty; but on the contrary ſhall find, that 'tis of a nature quite foreign to that ſpecies of conviction.

ALL certainty ariſes from the compari⯑ſon of ideas, and from the diſcovery of ſuch relations as are unalterable, ſo long as the ideas continue the ſame. Theſe relations are reſemblance, proportions in quantity and number, degrees of any quality, and contra⯑riety; none of which are imply'd in this propoſition, Whatever has a beginning has alſo a cauſe of exiſtence. That propoſi⯑tion therefore is not intuitively certain. At leaſt any one, who wou'd aſſert it to be in⯑tuitively certain, muſt deny theſe to be the only infallible relations, and muſt find ſome other relation of that kind to be imply'd in it; which it will then be time enough to examine.

BUT here is an argument, which proves at once, that the foregoing propoſition is [143] neither intuitively nor demonſtrably certain. We can never demonſtrate the neceſſity of a cauſe to every new exiſtence, or new mo⯑dification of exiſtence, without ſhewing at the ſame time the impoſſibility there is, that any thing can ever begin to exiſt without ſome productive principle; and where the latter propoſition cannot be prov'd, we muſt deſpair of ever being able to prove the for⯑mer. Now that the latter propoſition is utterly incapable of a demonſtrative proof, we may ſatisfy ourſelves by conſidering, that as all diſtinct ideas are ſeparable from each other, and as the ideas of cauſe and effect are evidently diſtinct, 'twill be eaſy for us to conceive any object to be non-exiſtent this moment, and exiſtent the next, with⯑out conjoining to it the diſtinct idea of a cauſe or productive principle. The ſepara⯑tion, therefore, of the idea of a cauſe from that of a beginning of exiſtence, is plainly poſſible for the imagination; and conſequent⯑ly the actual ſeparation of theſe objects is ſo far poſſible, that it implies no contra⯑diction nor abſurdity; and is therefore in⯑capable of being refuted by any reaſoning from mere ideas; without which 'tis impoſ⯑ſible to demonſtrate the neceſſity of a cauſe.

[144] ACCORDINGLY we ſhall find upon ex⯑amination, that every demonſtration, which has been produc'd for the neceſſity of a cauſe, is fallacious and ſophiſtical. All the points of time and place,^* ſay ſome philoſophers, in which we can ſuppoſe any object to be⯑gin to exiſt, are in themſelves equal; and unleſs there be ſome cauſe, which is pecu⯑liar to one time and to one place, and which by that means determines and fixes the exiſtence, it muſt remain in eternal ſuſ⯑pence; and the object can never begin to be, for want of ſomething to fix its beginning. But I aſk; Is there any more difficulty in ſuppoſing the time and place to be fix'd without a cauſe, than to ſuppoſe the exiſ⯑tence to be determin'd in that manner? The firſt queſtion that occurs on this ſub⯑ject is always, whether the object ſhall exiſt or not: The next, when and where it ſhall begin to exiſt. If the removal of a cauſe be intuitively abſurd in the one caſe, it muſt be ſo in the other: And if that abſurdity be not clear without a proof in the one caſe, it will equally require one in the other. The abſurdity, then, of the one ſuppoſition can never be a proof of that of the other; ſince [145] they are both upon the ſame footing, and muſt ſtand or fall by the ſame reaſoning.

THE ſecond argument,^* which I find us'd on this head, labours under an equal difficulty. Every thing, 'tis ſaid, muſt have a cauſe; for if any thing wanted a cauſe, it wou'd produce itſelf; that is, exiſt before it exiſted; which is impoſſible. But this reaſoning is plainly unconcluſive; becauſe it ſuppoſes, that in our denial of a cauſe we ſtill grant what we expreſly deny, viz. that there muſt be a cauſe; which therefore is taken to be the object itſelf; and that, no doubt, is an evident contradiction. But to ſay that any thing is produc'd, or to ex⯑preſs myſelf more properly, comes into ex⯑iſtence, without a cauſe, is not to affirm, that 'tis itſelf its own cauſe; but on the contrary in excluding all external cauſes, excludes a fortiori the thing itſelf, which is created. An object, that exiſts abſolutely without any cauſe, certainly is not its own cauſe; and when you aſſert, that the one follows from the other, you ſuppoſe the very point in queſtion, and take it for grant⯑ed, that 'tis utterly impoſſible any thing can ever begin to exiſt without a cauſe, but that upon the excluſion of one productive [146] principle, we muſt ſtill have recourſe to another.

'TIS exactly the ſame caſe with the ^* third argument, which has been employ'd to de⯑monſtrate the neceſſity of a cauſe. What⯑ever is produc'd without any cauſe, is pro⯑duc'd by nothing; or in other words, has nothing for its cauſe. But nothing can ne⯑ver be a cauſe, no more than it can be ſomething, or equal to two right angles. By the ſame intuition, that we perceive nothing not to be equal to two right angles, or not to be ſomething, we perceive, that it can never be a cauſe; and conſequently muſt perceive, that every object has a real cauſe of its exiſtence.

I BELIEVE it will not be neceſſary to employ many words in ſhewing the weak⯑neſs of this argument, after what I have ſaid of the foregoing. They are all of them founded on the ſame fallacy, and are de⯑riv'd from the ſame turn of thought. 'Tis ſufficient only to obſerve, that when we exclude all cauſes we really do exclude them, and neither ſuppoſe nothing nor the object itſelf to be the cauſes of the exiſtence; and conſequently can draw no argument from the abſurdity of theſe ſuppoſitions to prove [147] the abſurdity of that excluſion. If every thing muſt have a cauſe, it follows, that upon the excluſion of other cauſes we muſt accept of the object itſelf or of nothing as cauſes. But 'tis the very point in queſtion, whether every thing muſt have a cauſe or not; and therefore, according to all juſt reaſoning, it ought never to be taken for granted.

THEY are ſtill more frivolous, who ſay, that every effect muſt have a cauſe, becauſe 'tis imply'd in the very idea of effect. Eve⯑ry effect neceſſarily pre-ſuppoſes a cauſe; effect being a relative term, of which cauſe is the correlative. But this does not prove, that every being muſt be preceded by a cauſe; no more than it follows, becauſe every huſband muſt have a wife, that there⯑fore every man muſt be marry'd. The true ſtate of the queſtion is, whether every ob⯑ject, which begins to exiſt, muſt owe its exiſtence to a cauſe; and this I aſſert neither to be intuitively nor demonſtratively certain, and hope to have prov'd it ſufficiently by the foregoing arguments.

SINCE it is not from knowledge or any ſcientific reaſoning, that we derive the opi⯑nion of the neceſſity of a cauſe to every new production, that opinion muſt neceſſarily [148] ariſe from obſervation and experience. The next queſtion, then, ſhou'd naturally be, how experience gives riſe to ſuch a principle? But as I find it will be more convenient to ſink this queſtion in the following, Why we con⯑clude, that ſuch particular cauſes muſt neceſ⯑ſarily have ſuch particular effects, and why we form an inference from one to another? we ſhall make that the ſubject of our fu⯑ture enquiry. 'Twill, perhaps, be found in the end, that the ſame anſwer will ſerve for both queſtions.

SECT. IV. Of the component parts of our reaſon⯑ings concerning cauſe and effect.

THO' the mind in its reaſonings from cauſes or effects carries its view be⯑yond thoſe objects, which it ſees or remem⯑bers, it muſt never loſe ſight of them en⯑tirely, nor reaſon merely upon its own ideas, without ſome mixture of impreſſions, or at leaſt of ideas of the memory, which are equivalent to impreſſions. When we infer effects from cauſes, we muſt eſtabliſh the exiſtence of theſe cauſes; which we have only two ways of doing, either by an im⯑mediate [149] perception of our memory or ſenſes, or by an inference from other cauſes; which cauſes again we muſt aſcertain in the ſame manner, either by a preſent impreſſion, or by an inference from their cauſes, and ſo on, till we arrive at ſome object, which we ſee or remember. 'Tis impoſſible for us to carry on our inferences in infinitum; and the only thing, that can ſtop them, is an impreſſion of the memory or ſenſes, beyond which there is no room for doubt or en⯑quiry.

To give an inſtance of this, we may chuſe any point of hiſtory, and conſider for what reaſon we either believe or reject it. Thus we believe that CAESAR was kill'd in the ſenate-houſe on the ides of March; and that becauſe this fact is eſtabliſh'd on the un⯑animous teſtimony of hiſtorians, who agree to aſſign this preciſe time and place to that event. Here are certain characters and let⯑ters preſent either to our memory or ſenſes; which characters we likewiſe remember to have been us'd as the ſigns of certain ideas; and theſe ideas were either in the minds of ſuch as were immediately preſent at that action, and receiv'd the ideas directly from its exiſtence; or they were deriv'd from the teſtimony of others, and that again from [150] another teſtimony, by a viſible gradation, 'till we arrive at thoſe who were eye-wit⯑neſſes and ſpectators of the event. 'Tis ob⯑vious all this chain of argument or con⯑nexion of cauſes and effects, is at firſt found⯑ed on thoſe characters or letters, which are ſeen or remember'd, and that without the authority either of the memory or ſenſes our whole reaſoning wou'd be chimerical and without foundation. Every link of the chain wou'd in that caſe hang upon another; but there wou'd not be any thing fix'd to one end of it, capable of ſuſtaining the whole; and conſequently there wou'd be no belief nor evidence. And this actually is the caſe with all hypothetical arguments, or reaſon⯑ings upon a ſuppoſition; there being in them, neither any preſent impreſſion, nor belief of a real exiſtence.

I NEED not obſerve, that 'tis no juſt ob⯑jection to the preſent doctrine, that we can reaſon upon our paſt concluſions or princi⯑ples, without having recourſe to thoſe im⯑preſſions, from which they firſt aroſe. For even ſuppoſing theſe impreſſions ſhou'd be entirely effac'd from the memory, the conviction they produc'd may ſtill remain; and 'tis equally true, that all reaſonings con⯑cerning cauſes and effects are originally de⯑riv'd [151] from ſome impreſſion; in the ſame manner, as the aſſurance of a demonſtra⯑tion proceeds always from a compariſon of ideas, tho' it may continue after the com⯑pariſon is forgot.

SECT. V. Of the impreſſions of the ſenſes and memory.

IN this kind of reaſoning, then, from cauſation, we employ materials, which are of a mix'd and heterogeneous nature, and which, however connected, are yet eſ⯑ſentially different from each other. All our arguments concerning cauſes and effects con⯑ſiſt both of an impreſſion of the memory or ſenſes, and of the idea of that exiſtence, which produces the object of the impreſſion, or is produc'd by it. Here therefore we have three things to explain, viz. Firſt, The original impreſſion. Secondly, The tranſition to the idea of the connected cauſe or effect. Thirdly, The nature and quali⯑ties of that idea.

As to thoſe impreſſions, which ariſe from the ſenſes, their ultimate cauſe is, in my opinion, perfectly inexplicable by human [152] reaſon, and 'twill always be impoſſible to de⯑cide with certainty, whether they ariſe im⯑mediately from the object, or are produc'd by the creative power of the mind, or are deriv'd from the author of our being. Nor is ſuch a queſtion any way material to our preſent purpoſe. We may draw inferences from the coherence of our perceptions, whe⯑ther they be true or falſe; whether they repreſent nature juſtly, or be mere illuſions of the ſenſes.

WHEN we ſearch for the characteriſtic, which diſtinguiſhes the memory from the imagination, we muſt immediately perceive, that it cannot lie in the ſimple ideas it pre⯑ſents to us; ſince both theſe faculties bor⯑row their ſimple ideas from the impreſſions, and can never go beyond theſe original percep⯑tions. Theſe faculties are as little diſtinguiſh'd from each other by the arrangement of their complex ideas. For tho' it be a peculiar property of the memory to preſerve the original order and poſition of its ideas, while the imagination tranſpoſes and changes them, as it pleaſes; yet this difference is not ſuffi⯑cient to diſtinguiſh them in their operation, or make us know the one from the other; it being impoſſible to recal the paſt impreſ⯑ſions, in order to compare them with our [153] preſent ideas, and ſee whether their arrange⯑ment be exactly ſimilar. Since therefore the memory is known, neither by the order of its complex ideas, nor the nature of its ſimple ones; it follows, that the difference betwixt it and the imagination lies in its ſuperior force and vivacity. A man may indulge his fancy in feigning any paſt ſcene of adven⯑tures; nor wou'd there be any poſſibility of diſtinguiſhing this from a remembrance of a like kind, were not the ideas of the ima⯑gination fainter and more obſcure.

A PAINTER, who intended to repreſent a paſſion or emotion of any kind, wou'd endeavour to get a ſight of a perſon actua⯑ted by a like emotion, in order to enliven his ideas, and give them a force and viva⯑city ſuperior to what is found in thoſe, which are mere fictions of the imagination. The more recent this memory is, the clearer is the idea; and when after a long interval he would return to the contemplation of his object, he always finds its idea to be much decay'd, if not wholly obliterated. We are frequently in doubt concerning the ideas of the memory, as they become very weak and feeble; and are at a loſs to determine whether any image proceeds from the fancy or the memory, when it is not drawn in [154] ſuch lively colours as diſtinguiſh that latter faculty. I think, I remember ſuch an event, ſays one; but am not ſure. A long tract of time has almoſt worn out of my me⯑mory, and leaves me uncertain whether or not it be the pure offspring of my fancy.

AND as an idea of the memory, by loſing its force and vivacity, may degene⯑rate to ſuch a degree, as to be taken for an idea of the imagination; ſo on the other hand an idea of the imagination may acquire ſuch a force and vivacity, as to paſs for an idea of the memory, and counterfeit its ef⯑fects on the belief and judgment. This is noted in the caſe of liars; who by the fre⯑quent repetition of their lies, come at laſt to believe and remember them, as realities; cuſtom and habit having in this caſe, as in many others, the ſame influence on the mind as nature, and infixing the idea with equal force and vigour.

THUS it appears, that the belief or aſ⯑ſent, which always attends the memory and ſenſes, is nothing but the vivacity of thoſe perceptions they preſent; and that this a⯑lone diſtinguiſhes them from the imagina⯑tion. To believe is in this caſe to feel an immediate impreſſion of the ſenſes, or a re⯑petition of that impreſſion in the memory. [155] 'Tis merely the force and livelineſs of the perception, which conſtitutes the firſt act of the judgment, and lays the foundation of that reaſoning, which we build upon it, when we trace the relation of cauſe and effect.

SECT. VI. Of the inference from the impreſſion to the idea.

'TIS eaſy to obſerve, that in tracing this relation, the inference we draw from cauſe to effect, is not deriv'd mere⯑ly from a ſurvey of theſe particular objects, and from ſuch a penetration into their eſ⯑ſences as may diſcover the dependance of the one upon the other. There is no object, which implies the exiſtence of any other if we conſider theſe objects in themſelves, and never look beyond the ideas which we form of them. Such an inference wou'd amount to knowledge, and wou'd imply the abſo⯑lute contradiction and impoſſibility of con⯑ceiving any thing different. But as all diſtinct ideas are ſeparable, 'tis evident there can be no impoſſibility of that kind. When we paſs from a preſent impreſſion to the idea of any object, we might poſſibly have ſeparated the idea from the impreſſion, and [156] have ſubſtituted any other idea in its room.

'TIS therefore by EXPERIENCE only, that we can infer the exiſtence of one ob⯑ject from that of another. The nature of experience is this. We remember to have had frequent inſtances of the exiſtence of one ſpecies of objects; and alſo remember, that the individuals of another ſpecies of objects have always attended them, and have exiſted in a regular order of con⯑tiguity and ſucceſſion with regard to them. Thus we remember to have ſeen that ſpecies of object we call flame, and to have felt that ſpecies of ſenſation we call heat. We likewiſe call to mind their con⯑ſtant conjunction in all paſt inſtances. With⯑out any farther ceremony, we call the one cauſe and the other effect, and infer the ex⯑iſtence of the one from that of the other. In all thoſe inſtances, from which we learn the conjunction of particular cauſes and ef⯑fects, both the cauſes and effects have been perceiv'd by the ſenſes, and are remember'd: But in all caſes, wherein we reaſon concern⯑ing them, there is only one perceiv'd or remember'd, and the other is ſupply'd in conformity to our paſt experience.

THUS in advancing we have inſenſibly diſcover'd a new relation betwixt cauſe and [157] effect, when we leaſt expected it, and were entirely employ'd upon another ſubject. This relation is their CONSTANT CON⯑JUNCTION. Contiguity and ſucceſſion are not ſufficient to make us pronounce any two objects to be cauſe and effect, unleſs we perceive, that theſe two relations are pre⯑ſerv'd in ſeveral inſtances. We may now ſee the advantage of quitting the direct ſur⯑vey of this relation, in order to diſcover the nature of that neceſſary connexion, which makes ſo eſſential a part of it. There are hopes, that by this means we may at laſt arrive at our propos'd end; tho' to tell the truth, this new-diſcover'd relation of a con⯑ſtant conjunction ſeems to advance us but very little in our way. For it implies no more than this, that like objects have always been plac'd in like relations of contiguity and ſucceſſion; and it ſeems evident, at leaſt at firſt ſight, that by this means we can never diſcover any new idea, and can only multiply, but not enlarge the objects of our mind. It may be thought, that what we learn not from one object, we can never learn from a hundred, which are all of the ſame kind, and are perfectly reſembling in every circumſtance. As our ſenſes ſhew us in one inſtance two bodies, or motions, or qualities [158] in certain relations of ſucceſſion and conti⯑guity; ſo our memory preſents us only with a multitude of inſtances, wherein we al⯑ways find like bodies, motions, or qualities in like relations. From the mere repetition of any paſt impreſſion, even to infinity, there never will ariſe any new original idea, ſuch as that of a neceſſary connexion; and the number of impreſſions has in this caſe no more effect than if we confin'd ourſelves to one only. But tho' this reaſoning ſeems juſt and obvious; yet as it wou'd be folly to deſpair too ſoon, we ſhall continue the thread of our diſcourſe; and having found, that after the diſcovery of the conſtant con⯑junction of any objects, we always draw an in⯑ference from one object to another, we ſhall now examine the nature of that inference, and of the tranſition from the impreſſion to the idea. Perhaps 'twill appear in the end, that the neceſſary connexion depends on the inference, inſtead of the inference's depend⯑ing on the neceſſary connexion.

SINCE it appears, that the tranſition from an impreſſion preſent to the memory or ſenſes to the idea of an object, which we call cauſe or effect, is founded on paſt experience, and on our remembrance of their conſtant conjunction, the next queſtion [159] is, Whether experience produces the idea by means of the underſtanding or imagination; whether we are determin'd by reaſon to make the tranſition, or by a certain aſſociation and relation of perceptions. If reaſon determin'd us, it wou'd proceed upon that principle, that inſtances, of which we have had no expe⯑rience, muſt reſemble thoſe, of which we have had experience, and that the courſe of nature continues always uniformly the ſame. In or⯑der therefore to clear up this matter, let us conſider all the arguments, upon which ſuch a propoſition may be ſuppos'd to be found⯑ed; and as theſe muſt be deriv'd either from knowledge or probability, let us caſt our eye on each of theſe degrees of evidence, and ſee whether they afford any juſt concluſion of this nature.

OUR foregoing method of reaſoning will eaſily convince us, that there can be no de⯑monſtrative arguments to prove, that thoſe inſtances, of which we have had no experi⯑ence, reſemble thoſe, of which we have had experience. We can at leaſt conceive a change in the courſe of nature; which ſufficiently proves, that ſuch a change is not abſolutely impoſſible. To form a clear idea of any thing, is an undeniable argument for its poſſibi⯑lity, [160] and is alone a refutation of any pre⯑tended demonſtration againſt it.

PROBABILITY, as it diſcovers not the relations of ideas, conſider'd as ſuch, but only thoſe of objects, muſt in ſome reſpects be founded on the impreſſions of our me⯑mory and ſenſes, and in ſome reſpects on our ideas. Were there no mixture of any im⯑preſſion in our probable reaſonings, the con⯑cluſion wou'd be entirely chimerical: And were there no mixture of ideas, the action of the mind, in obſerving the relation, wou'd, properly ſpeaking, be ſenſation, not rea⯑ſoning. 'Tis therefore neceſſary, that in all probable reaſonings there be ſomething pre⯑ſent to the mind, either ſeen or remember'd; and that from this we infer ſomething con⯑nected with it, which is not ſeen nor re⯑member'd.

THE only connexion or relation of ob⯑jects, which can lead us beyond the imme⯑diate impreſſions of our memory and ſen⯑ſes, is that of cauſe and effect; and that becauſe 'tis the only one, on which we can found a juſt inference from one object to another. The idea of cauſe and effect is deriv'd from experience, which informs us, that ſuch particular objects, in all paſt in⯑ſtances, have been conſtantly conjoin'd with [161] each other: And as an object ſimilar to one of theſe is ſuppos'd to be immediately pre⯑ſent in its impreſſion, we thence preſume on the exiſtence of one ſimilar to its uſual attendant. According to this account of things, which is, I think, in every point unqueſtionable, probability is founded on the preſumption of a reſemblance betwixt thoſe objects, of which we have had expe⯑rience, and thoſe, of which we have had none; and therefore 'tis impoſſible this pre⯑ſumption can ariſe from probability. The ſame principle cannot be both the cauſe and effect of another; and this is, perhaps, the only propoſition concerning that relation, which is either intuitively or demonſtratively certain.

SHOU'D any one think to elude this ar⯑gument; and without determining whether our reaſoning on this ſubject be deriv'd from demonſtration or probability, pretend that all concluſions from cauſes and effects are bullt on ſolid reaſoning: I can only deſire, that this reaſoning may be produc'd, in or⯑der to be expos'd to our examination. It may, perhaps, be ſaid, that after experience of the conſtant conjunction of certain ob⯑jects, we reaſon in the following manner. Such an object is always found to produce [163] another. 'Tis impoſſible it cou'd have this effect, if it was not endow'd with a power of production. The power neceſſarily im⯑plies the effect; and therefore there is a juſt foundation for drawing a concluſion from the exiſtence of one object to that of its uſual attendant. The paſt production im⯑plies a power: The power implies a new production: And the new production is what we infer from the power and the paſt pro⯑duction.

'TWERE eaſy for me to ſhew the weak⯑neſs of this reaſoning, were I willing to make uſe of thoſe obſervations, I have already made, that the idea of production is the ſame with that of cauſation, and that no exiſtence certainly and demonſtratively implies a power in any other object; or were it proper to anticipate what I ſhall have occaſion to remark afterwards concern⯑ing the idea we form of power and efficacy. But as ſuch a method of proceeding may ſeem either to weaken my ſyſtem, by reſt⯑ing one part of it on another, or to breed a confuſion in my reaſoning, I ſhall endea⯑vour to maintain my preſent aſſertion with⯑out any ſuch aſſiſtance.

IT ſhall therefore be allow'd for a mo⯑ment, that the production of one object by [163] another in any one inſtance implies a power; and that this power is connected with its effect. But it having been already prov'd, that the power lies not in the ſenſible qua⯑lities of the cauſe; and there being nothing but the ſenſible qualities preſent to us; I aſk, why in other inſtances you preſume that the ſame power ſtill exiſts, merely up⯑on the appearance of theſe qualities? Your appeal to paſt experience decides nothing in the preſent caſe; and at the utmoſt can only prove, that that very object, which produc'd any other, was at that very inſtant endow'd with ſuch a power; but can never prove, that the ſame power muſt continue in the ſame object or collection of ſenſible qualities; much leſs, that a like power is always conjoin'd with like ſenſible qualities. Shou'd it be ſaid, that we have experience, that the ſame power continues united with the ſame object, and that like objects are endow'd with like powers, I wou'd renew my queſ⯑tion, why from this experience we form any concluſion beyond thoſe paſt inſtances, of which we have had experience. If you anſwer this queſtion in the ſame manner as the pre⯑ceding, your anſwer gives ſtill occaſion to a new queſtion of the ſame kind, even in infinitum; which clearly proves, that the [164] foregoing reaſoning had no juſt founda⯑tion.

THUS not only our reaſon fails us in the diſcovery of the ultimate connexion of cauſes and effects, but even after experience has inform'd us of their conſtant conjunction, 'tis impoſſible for us to ſatisfy ourſelves by our reaſon, why we ſhou'd extend that expe⯑rience beyond thoſe particular inſtances, which have fallen under our obſervation. We ſuppoſe, but are never able to prove, that there muſt be a reſemblance betwixt thoſe objects, of which we have had expe⯑rience, and thoſe which lie beyond the reach of our diſcovery.

WE have already taken notice of certain relations, which make us paſs from one ob⯑ject to another, even tho' there be no reaſon to determine us to that tranſition; and this we may eſtabliſh for a general rule, that wherever the mind conſtantly and uniformly makes a tranſition without any reaſon, it is influenc'd by theſe relations. Now this is exactly the preſent caſe. Reaſon can never ſhew us the connexion of one object with another, tho' aided by experience, and the obſervation of their conſtant conjunction in all paſt inſtances. When the mind, there⯑fore, paſſes from the idea or impreſſion of [165] one object to the idea or belief of another, it is not determin'd by reaſon, but by cer⯑tain principles, which aſſociate together the ideas of theſe objects, and unite them in the imagination. Had ideas no more union in the fancy than objects ſeem to have to the underſtanding, we cou'd never draw any inference from cauſes to effects, nor repoſe belief in any matter of fact. The inference, therefore, depends ſolely on the union of ideas.

THE principles of union among ideas, I have reduc'd to three general ones, and have aſſerted, that the idea or impreſſion of any object naturally introduces the idea of any other object, that is reſembling, conti⯑guous to, or connected with it. Theſe principles I allow to be neither the infalli⯑ble nor the ſole cauſes of an union among ideas. They are not the infallible cauſes. For one may fix his attention during ſome time on any one object without looking farther. They are not the ſole cauſes. For the thought has evidently a very irregular motion in run⯑ning along its objects, and may leap from the heavens to the earth, from one end of the creation to the other, without any cer⯑tain method or order. But tho' I allow this weakneſs in theſe three relations, and [166] this irregularity in the imagination; yet I aſſert that the only general principles, which aſſociate ideas, are reſemblance, contiguity and cauſation.

THERE is indeed a principle of union among ideas, which at firſt ſight may be eſteem'd different from any of theſe, but will be found at the bottom to depend on the ſame origin. When ev'ry individual of any ſpecies of objects is found by experience to be conſtantly united with an individual of another ſpecies, the appearance of any new individual of either ſpecies naturally conveys the thought to its uſual attendant. Thus becauſe ſuch a particular idea is com⯑monly annex'd to ſuch a particular word, nothing is requir'd but the hearing of that word to produce the correſpondent idea; and 'twill ſcarce be poſſible for the mind, by its utmoſt efforts, to prevent that tranſi⯑tion. In this caſe it is not abſolutely ne⯑ceſſary, that upon hearing ſuch a particular ſound, we ſhou'd reflect on any paſt expe⯑rience, and conſider what idea has been uſually connected with the ſound. The imagination of itſelf ſupplies the place of this reflection, and is ſo accuſtom'd to paſs from the word to the idea, that it inter⯑poſes not a moment's delay betwixt the [167] hearing of the one, and the conception of the other.

BUT tho' I acknowledge this to be a true principle of aſſociation among ideas, I aſſert it to be the very ſame with that be⯑twixt the ideas of cauſe and effect, and to be an eſſential part in all our reaſonings from that relation. We have no other no⯑tion of cauſe and effect, but that of certain objects, which have been always conjoin'd together, and which in all paſt inſtan⯑ces have been found inſeparable. We can⯑not penetrate into the reaſon of the con⯑junction. We only obſerve the thing itſelf, and always find that from the conſtant con⯑junction the objects acquire an union in the imagination. When the impreſſion of one becomes preſent to us, we immediately form an idea of its uſual attendant; and conſe⯑quently we may eſtabliſh this as one part of the definition of an opinion or belief, that 'tis an idea related to or aſſociated with a preſent impreſſion.

THUS tho' cauſation be a philoſophical relation, as implying contiguity, ſucceſſion, and conſtant conjunction, yet 'tis only ſo far as it is a natural relation, and produces an union among our ideas, that we are able to reaſon upon it, or draw any inference from it.

SECT. VII. Of the nature of the idea or belief.

THE idea of an object is an eſſential part of the belief of it, but not the whole. We conceive many things, which we do not believe. In order then to diſ⯑cover more fully the nature of belief, or the qualities of thoſe ideas we aſſent to, let us weigh the following conſiderations.

'TIS evident, that all reaſonings from cauſes or effects terminate in concluſions, concerning matter of fact; that is, concern⯑ing the exiſtence of objects or of their qua⯑lities. 'Tis alſo evident, that the idea oſ exiſtence is nothing different from the idea of any object, and that when after the ſim⯑ple conception of any thing we wou'd con⯑ceive it as exiſtent, we in reality make no addition to or alteration on our firſt idea. Thus when we affirm, that God is exiſtent, we ſimply form the idea of ſuch a being, as he is repreſented to us; nor is the exiſtence, which we attribute to him, conceiv'd by a particular idea, which we join to the idea of his other qualities, and can again ſepa⯑rate [169] and diſtinguiſh from them. But I go farther; and not content with aſſerting, that the conception of the exiſtence of any ob⯑ject is no addition to the ſimple conception of it, I likewiſe maintain, that the belief of the exiſtence joins no new ideas to thoſe, which compoſe the idea of the object. When I think of God, when I think of him as exiſtent, and when I believe him to be exiſtent, my idea of him neither en⯑creaſes nor diminiſhes. But as 'tis certain there is a great difference betwixt the ſimple conception of the exiſtence of an object, and the belief of it, and as this difference lies not in the parts or compoſition of the idea, which we conceive; it follows, that it muſt lie in the manner, in which we con⯑ceive it.

SUPPOSE a perſon preſent with me, who advances propoſitions, to which I do not aſſent, that Caeſar dy'd in his bed, that ſilver is more fuſible than lead, or mercury beavier than gold; 'tis evident, that notwithſtand⯑ing my incredulity, I clearly underſtand his meaning, and form all the ſame ideas, which he forms. My imagination is endow'd with the ſame powers as his; nor is it poſ⯑ſible for him to conceive any idea, which I cannot conceive; or conjoin any, which I [170] cannot conjoin. I therefore aſk, Wherein conſiſts the difference betwixt believing and diſbelieving any propoſition? The anſwer is eaſy with regard to propoſitions, that are prov'd by intuition or demonſtration. In that caſe, the perſon, who aſſents, not only conceives the ideas according to the propo⯑ſition, but is neceſſarily determin'd to con⯑ceive them in that particular manner, either immediately or by the interpoſition of other ideas. Whatever is abſurd is unintelligible; nor is it poſſible for the imagination to con⯑ceive any thing contrary to a demonſtration. But as in reaſonings from cauſation, and concerning matters of fact, this abſolute ne⯑ceſſity cannot take place, and the imagina⯑tion is free to conceive both ſides of the queſtion, I ſtill aſk, Wherein conſiſts the difference betwixt incredulity and belief? ſince in both caſes the conception of the idea is equally poſſible and requiſite.

'TWILL not be a ſatisfactory anſwer to ſay, that a perſon, who does not aſſent to a propoſition you advance; after having conceiv'd the object in the ſame manner with you; immediately conceives it in a different manner, and has different ideas of it. This anſwer is unſatisfactory; not be⯑cauſe it contains any falſhood, but becauſe [171] it diſcovers not all the truth. 'Tis confeſt, that in all caſes, wherein we diſſent from any perſon, we conceive both ſides of the queſtion; but as we can believe only one, it evidently follows, that the belief muſt make ſome difference betwixt that concep⯑tion to which we aſſent, and that from which we diſſent. We may mingle, and unite, and ſeparate, and confound, and vary our ideas in a hundred different ways; but 'till there appears ſome principle, which fixes one of theſe different ſituations, we have in reality no opinion: And this principle, as it plainly makes no addition to our prece⯑dent ideas, can only change the manner of our conceiving them.

ALL the perceptions of the mind are of two kinds, viz. impreſſions and ideas, which differ from each other only in their dif⯑ferent degrees of force and vivacity. Our ideas are copy'd from our impreſſions, and repreſent them in all their parts. When you wou'd any way vary the idea of a par⯑ticular object, you can only encreaſe or di⯑miniſh its force and vivacity. If you make any other change on it, it repreſents a dif⯑ferent object or impreſſion. The caſe is the ſame as in colours. A particular ſhade of any colour may acquire a new degree of [172] livelineſs or brightneſs without any other va⯑riation. But when you produce any other variation, 'tis no longer the ſame ſhade or colour. So that as belief does nothing but vary the manner, in which we conceive any object, it can only beſtow on our ideas an additional force and vivacity. An opinion, therefore, or belief may be moſt accurately defin'd, A LIVELY IDEA RELATED TO OR ASSOCIATED WITH A PRESENT IM⯑PRESSION ^*.

[173] HERE are the heads of thoſe arguments, which lead us to this concluſion. When we infer the exiſtence of an object from that of others, ſome object muſt always be preſent either to the memory or ſenſes, in order to be the foundation of our reaſoning; ſince the mind cannot run up with its infe⯑rences in infinitum. Reaſon can never ſa⯑tisfy us that the exiſtence of any one ob⯑ject does ever imply that of another; ſo that when we paſs from the impreſſion of one to the idea or belief of another, we are not determin'd by reaſon, but by cuſtom or a principle of aſſociation. But belief is ſome⯑what [174] more than a ſimple idea. 'Tis a par⯑ticular manner of forming an idea: And as the ſame idea can only be vary'd by a va⯑riation of its degrees of force and vivacity; it follows upon the whole, that belief is a lively idea produc'd by a relation to a pre⯑ſent impreſſion, according to the foregoing definition. [...].

THIS definition will alſo be found to be entirely conformable to every one's feeling and experience. Nothing is more evident, than that thoſe ideas, to which we aſſent, are more ſtrong, firm and vivid, than the looſe reveries of a caſtle-builder. If one perſon ſits down to read a book as a ro⯑mance, and another as a true hiſtory, they plainly receive the ſame ideas, and in the ſame order; nor does the incredulity of the one, and the belief of the other hinder them from putting the very ſame ſenſe upon their author. His words produce the ſame ideas in both; tho' his teſtimony has not the ſame influence on them. The latter has a more lively conception of all the incidents. He enters deeper into the concerns of the per⯑ſons: repreſents to himſelf their actions, and characters, and friendſhips, and enmities: He even goes ſo far as to form a notion of their features, and air, and perſon. While [175] the former, who gives no credit to the teſ⯑timony of the author, has a more faint and languid conception of all theſe particulars; and except on account of the ſtyle and in⯑genuity of the compoſition, can receive little entertainment from it.

SECT. VIII. Of the cauſes of belief.

HAVING thus explain'd the nature of belief, and ſhewn that it conſiſts in a lively idea related to a preſent impreſ⯑ſion; let us now proceed to examine from what principles it is deriv'd, and what be⯑ſtows the vivacity on the idea.

I WOU'D willingly eſtabliſh it as a ge⯑neral maxim in the ſcience of human na⯑ture, that when any impreſſion becomes preſent to us, it not only tranſports the mind to ſuch ideas as are related to it, but likewiſe com⯑municates to them a ſhare of its force and vivacity. All the operations of the mind depend in a great meaſure on its diſpoſition, when it performs them; and according as the ſpirits are more or leſs elevated, and the attention more or leſs fix'd, the action will always have more or leſs vigour and vi⯑vacity. [176] When therefore any object is pre⯑ſented, which elevates and enlivens the thought, every action, to which the mind applies itſelf, will be more ſtrong and vi⯑vid, as long as that diſpoſition continues. Now 'tis evident the continuance of the diſ⯑poſition depends entirely on the objects, about which the mind is employ'd; and that any new object naturally gives a new direction to the ſpirits, and changes the diſpoſition; as on the contrary, when the mind fixes conſtant⯑ly on the ſame object, or paſſes eaſily and inſenſibly along related objects, the diſpo⯑ſition has a much longer duration. Hence it happens, that when the mind is once in⯑liven'd by a preſent impreſſion, it proceeds to form a more lively idea of the related objects, by a natural tranſition of the diſ⯑poſition from the one to the other. The change of the objects is ſo eaſy, that the mind is ſcarce ſenſible of it, but applies it⯑ſelf to the conception of the related idea with all the force and vivacity it acquir'd from the preſent impreſſion.

IF in conſidering the nature of relation, and that facility of tranſition, which is eſſen⯑tial to it, we can ſatisfy ourſelves concerning the reality of this phaenomenon, 'tis well: But I muſt confeſs I place my chief con⯑fidence [177] in experience to prove ſo material a principle. We may, therefore, obſerve, as the firſt experiment to our preſent purpoſe, that upon the appearance of the picture of an abſent friend, our idea of him is evi⯑dently inliven'd by the reſemblance, and that every paſſion, which that idea occaſions, whether of joy or ſorrow, acquires new force and vigour. In producing this effect there concur both a relation and a preſent impreſſion. Where the picture bears him no reſemblance, or at leaſt was not intend⯑ed for him, it never ſo much as conveys our thought to him: And where it is ab⯑ſent, as well as the perſon; tho' the mind may paſs from the thought of the one to that of the other; it feels its idea to be ra⯑ther weaken'd than inliven'd by that tranſi⯑tion. We take a pleaſure in viewing the picture of a friend, when 'tis ſet before us; but when 'tis remov'd, rather chooſe to conſider him directly, than by reflexion in an image, which is equally diſtant and ob⯑ſcure.

THE ceremonies of the Roman Catholic religion may be conſider'd as experiments of the ſame nature. The devotees of that ſtrange ſuperſtition uſually plead in excuſe of the mummeries, with which they are [178] upbraided, that they feel the good effect of thoſe external motions, and poſtures, and actions, in inlivening their devotion, and quickening their fervour, which otherwiſe wou'd decay away, if directed entirely to diſtant and immaterial objects. We ſhadow out the objects of our faith, ſay they, in ſenſible types and images, and render them more preſent to us by the immediate pre⯑ſence of theſe types, that 'tis poſſible for us to do, merely by an intellectual view and contemplation. Senſible objects have always a greater influence on the fancy than any other; and this influence they readily con⯑vey to thoſe ideas, to which they are re⯑lated, and which they reſemble. I ſhall only infer from theſe practices, and this reaſoning, that the effect of reſemblance in inlivening the idea is very common; and as in every caſe a reſemblance and a preſent impreſſion muſt concur, we are abundantly ſupply'd with experiments to prove the re⯑ality of the foregoing principle.

WE may add force to theſe experiments by others of a different kind, in conſidering the effects of contiguity, as well as of re⯑ſemblance. 'Tis certain, that diſtance dimi⯑niſhes the force of every idea, and that upon our approach to any object; tho' it does not [179] diſcover itſelf to our ſenſes; it operates upon the mind with an influence that imitates an immediate impreſſion. The thinking on any object readily tranſports the mind to what is contiguous; but 'tis only the actual preſence of an object, that tranſports it with a ſuperior vivacity. When I am a few miles from home, whatever relates to it touches me more nearly than when I am two hundred leagues diſtant; tho' even at that diſtance the reflecting on any thing in the neighbourhood of my friends and fa⯑mily naturally produces an idea of them. But as in this latter caſe, both the objects of the mind are ideas; notwithſtanding there is an eaſy tranſition betwixt them; that tranſition alone is not able to give a ſupe⯑rior vivacity to any of the ideas, for want of ſome immediate impreſſion.

No one can doubt but cauſation has the ſame influence as the other two relations of reſemblance and contiguity. Superſtitious people are fond of the relicts of ſaints and holy men, for the ſame reaſon that they ſeek after types and images, in order to in⯑liven their devotion, and give them a more intimate and ſtrong conception of thoſe ex⯑emplary lives, which they deſire to imitate. Now 'tis evident, one of the beſt relicks a [180] devotee cou'd procure, wou'd be the handy⯑work of a ſaint; and if his cloaths and fur⯑niture are ever to be conſider'd in this light, 'tis becauſe they were once at his diſpoſal, and were mov'd and affected by him; in which reſpect they are to be conſider'd as imperfect effects, and as connected with him by a ſhorter chain of conſequences than any of thoſe, from which we learn the reality of his exiſtence. This phaenomenon clearly proves, that a preſent impreſſion with a relation of cauſation may enliven any idea, and conſequently produce belief or aſſent, according to the precedent definition of it.

BUT why need we ſeek for other ar⯑guments to prove, that a preſent impreſſion with a relation or tranſition of the fancy may inliven any idea, when this very inſtance of our reaſonings from cauſe and effect will alone ſuffice to that purpoſe? 'Tis certain we muſt have an idea of every matter of fact, which we believe. 'Tis certain, that this idea ariſes only from a re⯑lation to a preſent impreſſion. 'Tis certain, that the belief ſuper-adds nothing to the idea, but only changes our manner of con⯑ceiving it, and renders it more ſtrong and lively. The preſent concluſion concerning [181] the influence of relation is the immediate conſequence of all theſe ſteps; and every ſtep appears to me ſure and infallible. There enters nothing into this operation of the mind but a preſent impreſſion, a lively idea, and a relation or aſſociation in the fancy betwixt the impreſſion and idea; ſo that there can be no ſuſpicion of miſtake.

IN order to put this whole affair in a fuller light, let us conſider it as a queſtion in natural philoſophy, which we muſt de⯑termine by experience and obſervation. I ſuppoſe there is an object preſented, from which I draw a certain concluſion, and form to myſelf ideas, which I am ſaid to believe or aſſent to. Here 'tis evident, that how⯑ever that object, which is preſent to my ſenſes, and that other, whoſe exiſtence I infer by reaſoning, may be thought to in⯑fluence each other by their particular powers or qualities; yet as the phaenomenon of belief, which we at preſent examine, is merely internal, theſe powers and qualities, being entirely unknown, can have no hand in producing it. 'Tis the preſent impreſſion, which is to be conſider'd as the true and real cauſe of the idea, and of the belief which attends it. We muſt therefore en⯑deavour to diſcover by experiments the par⯑ticular [182] qualities, by which 'tis enabled to produce ſo extraordinary an effect.

FIRST then I obſerve, that the preſent impreſſion has not this effect by its own proper power and efficacy, and when con⯑ſider'd alone, as a ſingle perception, limited to the preſent moment. I find, that an im⯑preſſion, from which, on its firſt appearance, I can draw no concluſion, may afterwards become the foundation of belief, when I have had experience of its uſual conſequen⯑ces. We muſt in every caſe have obſerv'd the ſame impreſſion in paſt inſtances, and have found it to be conſtantly conjoin'd with ſome other impreſſion. This is con⯑firm'd by ſuch a multitude of experiments, that it admits not of the ſmalleſt doubt.

FROM a ſecond obſervation I conclude, that the belief, which attends the preſent impreſſion, and is produc'd by a number of paſt impreſſions and conjunctions; that this belief, I ſay, ariſes immediately, without any new operation of the reaſon or imagination. Of this I can be certain, becauſe I never am conſcious of any ſuch operation, and find nothing in the ſubject, on which it can be founded. Now as we call every thing CUSTOM, which proceeds from a paſt re⯑petition, without any new reaſoning or con⯑cluſion, [183] we may eſtabliſh it as a certain truth, that all the belief, which follows upon any preſent impreſſion, is deriv'd ſolely from that origin. When we are accuſtom'd to ſee two impreſſions conjoin'd together, the appearance or idea of the one immediately carries us to the idea of the other.

BEING fully ſatisfy'd on this head, I make a third ſet of experiments, in order to know, whether any thing be requiſite, be⯑ſide the cuſtomary tranſition, towards the production of this phaenomenon of belief. I therefore change the firſt impreſſion into an idea; and obſerve, that tho' the cuſtom⯑ary tranſition to the correlative idea ſtill re⯑mains, yet there is in reality no belief nor perſwaſion. A preſent impreſſion, then, is abſolutely requiſite to this whole operation; and when after this I compare an impreſſion with an idea, and find that their only diffe⯑rence conſiſts in their different degrees of force and vivacity, I conclude upon the whole, that belief is a more vivid and in⯑tenſe conception of an idea, proceeding from its relation to a preſent impreſſion.

THUS all probable reaſoning is nothing but a ſpecies of ſenſation. 'Tis not ſolely in poetry and muſic, we muſt follow our taſte and ſentiment, but likewiſe in philoſophy. [184] When I am convinc'd of any principle, 'tis only an idea, which ſtrikes more ſtrongly upon me. When I give the preference to one ſet of arguments above another, I do nothing but decide from my feeling con⯑cerning the ſuperiority of their influence. Objects have no diſcoverable connexion to⯑gether; nor is it from any other principle but cuſtom operating upon the imagination, that we can draw any inference from the appearance of one to the exiſtence of ano⯑ther.

'TWILL here be worth our obſervation, that the paſt experience, on which all our judgments concerning cauſe and effect de⯑pend, may operate on our mind in ſuch an inſenſible manner as never to be taken no⯑tice of, and may even in ſome meaſure be un⯑known to us. A perſon, who ſtops ſhort in his journey upon meeting a river in his way, foreſees the conſequences of his pro⯑ceeding forward; and his knowledge of theſe conſequences is convey'd to him by paſt experience, which informs him of ſuch cer⯑tain conjunctions of cauſes and effects. But can we think, that on this occaſion he re⯑flects on any paſt experience, and calls to remembrance inſtances, that he has ſeen or heard of, in order to diſcover the effects of [185] water on animal bodies? No ſurely; this is not the method, in which he proceeds in his reaſoning. The idea of ſinking is ſo cloſely connected with that of water, and the idea of ſuffocating with that of ſinking, that the mind makes the tranſition without the aſſiſtance of the memory. The cuſtom operates before we have time for reflection. The objects ſeem ſo inſeparable, that we in⯑terpoſe not a moment's delay in paſſing from the one to the other. But as this tranſition proceeds from experience, and not from any primary connexion betwixt the ideas, we muſt neceſſarily acknowledge, that experience may produce a belief and a judgment of cauſes and effects by a ſecret operation, and with⯑out being once thought of. This removes all pretext, if there yet remains any, for aſſerting that the mind is convinc'd by rea⯑ſoning of that principle, that inſtances of which we have no experience, muſt neceſſa⯑rily reſemble thoſe, of which we have. For we here find, that the underſtanding or imagination can draw inferences from paſt experience, without reflecting on it; much more without forming any principle con⯑cerning it, or reaſoning upon that prin⯑ciple.

[186] IN general we may obſerve, that in all the moſt eſtabliſh'd and uniform conjunc⯑tions of cauſes and effects, ſuch as thoſe of gravity, impulſe, ſolidity, &c. the mind never carries its view expreſſly to conſider any paſt experience: Tho' in other aſſoci⯑ations of objects, which are more rare and unuſual, it may aſſiſt the cuſtom and tran⯑ſition of ideas by this reflection. Nay we find in ſome caſes, that the reflection pro⯑duces the belief without the cuſtom; or more properly ſpeaking, that the reflection produces the cuſtom in an oblique and ar⯑tificial manner. I explain myſelf. 'Tis certain, that not only in philoſophy, but even in common life, we may attain the knowledge of a particular cauſe merely by one experiment, provided it be made with judgment, and after a careful removal of all foreign and ſuperfluous circumſtances. Now as after one experiment of this kind, the mind, upon the appearance either of the cauſe or the effect, can draw an inference concerning the exiſtence of its correlative; and as a habit can never be acquir'd merely by one inſtance; it may be thought, that belief cannot in this caſe be eſteem'd the effect of cuſtom. But this difficulty will vaniſh, if we conſider, that tho' we are [187] here ſuppos'd to have had only one expe⯑riment of a particular effect, yet we have many millions to convince us of this principle; that like objects, plac'd in like circumſtances, will always produce like ef⯑fects; and as this principle has eſtabliſh'd itſelf by a ſufficient cuſtom, it beſtows an evidence and firmneſs on any opinion, to which it can be apply'd. The connexion of the ideas is not habitual after one ex⯑periment; but this connexion is compre⯑hended under another principle, that is ha⯑bitual; which brings us back to our hypo⯑theſis. In all caſes we transfer our experi⯑ence to inſtances, of which we have no experience, either expreſsly or tacitly, either directly or indirectly.

I MUST not conclude this ſubject with⯑out obſerving, that 'tis very difficult to talk of the operations of the mind with perfect propriety and exactneſs; becauſe common language has ſeldom made any very nice diſtinctions among them, but has generally call'd by the ſame term all ſuch as nearly reſemble each other. And as this is a ſource almoſt inevitable of obſcurity and confuſion in the author; ſo it may frequently give riſe to doubts and objections in the reader, which otherwiſe he wou'd never have dream'd [188] of. Thus my general poſition, that an opi⯑nion or belief is nothing but a ſtrong and lively idea deriv'd from a preſent impreſſion re⯑lated to it, may be liable to the following ob⯑jection, by reaſon of a little ambiguity in thoſe words ſtrong and lively. It may be ſaid, that not only an impreſſion may give riſe to reaſoning, but that an idea may alſo have the ſame influence; eſpecially upon my prin⯑ciple, that all our ideas are deriv'd from correſpondent impreſſions. For ſuppoſe I form at preſent an idea, of which I have forgot the correſpondent impreſſion, I am able to conclude from this idea, that ſuch an impreſſion did once exiſt; and as this concluſion is attended with belief, it may be aſk'd, from whence are the qua⯑lities of force and vivacity deriv'd, which conſtitute this belief? And to this I anſwer very readily, from the preſent idea. For as this idea is not here conſider'd, as the re⯑preſentation of any abſent object, but as a real perception in the mind, of which we are intimately conſcious, it muſt be able to beſtow on whatever is related to it the ſame quality, call it firmneſs, or ſolidity, or force, or vivacity, with which the mind reflects upon it, and is aſſur'd of its preſent exiſ⯑tence. The idea here ſupplies the place of [189] an impreſſion, and is entirely the ſame, ſo far as regards our preſent purpoſe.

UPON the ſame principles we need not be ſurpriz'd to hear of the remembrance of an idea; that is, of the idea of an idea, and of its force and vivacity ſuperior to the looſe conceptions of the imagination. In thinking of our paſt thoughts we not only delineate out the objects, of which we were thinking, but alſo conceive the action of the mind in the meditation, that certain je-ne-ſcai-quoi, of which 'tis impoſſible to give any definition or deſcription, but which e⯑very one ſufficiently underſtands. When the memory offers an idea of this, and re⯑preſents it as paſt, 'tis eaſily conceiv'd how that idea may have more vigour and firm⯑neſs, than when we think of a paſt thought, of which we have no remembrance.

AFTER this any one will underſtand how we may form the idea of an im⯑preſſion and of an idea, and how we may believe the exiſtence of an impreſſion and of an idea.

SECT. IX. Of the effects of other relations and other habits.

HOWEVER convincing the forego⯑ing arguments may appear, we muſt not reſt contented with them, but muſt turn the ſubject on every ſide, in order to find ſome new points of view, from which we may illuſtrate and confirm ſuch extraordi⯑nary, and ſuch fundamental principles. A ſcrupulous heſitation to receive any new hypotheſis is ſo laudable a diſpoſition in philoſophers, and ſo neceſſary to the exami⯑nation of truth, that it deſerves to be com⯑ply'd with, and requires that every argu⯑ment be produc'd, which may tend to their ſatisfaction, and every objection remov'd, which may ſtop them in their reaſoning.

I HAVE often obſerv'd, that, beſide cauſe and effect, the two relations of re⯑ſemblance and contiguity, are to be conſi⯑der'd as aſſociating principles of thought, and as capable of conveying the imagina⯑tion from one idea to another. I have alſo obſerv'd, that when of two objects connec⯑ted [191] together by any of theſe relations, one is immediately preſent to the memory or ſenſes, not only the mind is convey'd to its co-relative by means of the aſſociating prin⯑ciple; but likewiſe conceives it with an ad⯑ditional force and vigour, by the united o⯑peration of that principle, and of the preſent impreſſion. All this I have obſerv'd, in order to confirm by analogy, my explication of our judgments concerning cauſe and effect. But this very argument may, perhaps, be turn'd againſt me, and inſtead of a confir⯑mation of my hypotheſis, may become an objection to it. For it may be ſaid, that if all the parts of that hypotheſis be true, viz. that theſe three ſpecies of relation are deriv'd from the ſame principles; that their effects in inforcing and inlivening our ideas are the ſame; and that belief is no⯑thing but a more forcible and vivid concep⯑tion of an idea; it ſhou'd follow, that that action of the mind may not only be deriv'd from the relation of cauſe and effect, but alſo from thoſe of contiguity and reſem⯑blance. But as we find by experience, that belief ariſes only from cauſation, and that we can draw no inference from one object to another, except they be connected by this relation, we may conclude, that [192] there is ſome error in that reaſoning, which leads us into ſuch difficulties.

THIS is the objection; let us now con⯑ſider its ſolution. 'Tis evident, that what⯑ever is preſent to the memory, ſtriking up⯑on the mind with a vivacity, which re⯑ſembles an immediate impreſſion, muſt be⯑come of conſiderable moment in all the o⯑perations of the mind, and muſt eaſily di⯑ſtinguiſh itſelf above the mere fictions of the imagination. Of theſe impreſſions or ideas of the memory we form a kind of ſyſtem, comprehending whatever we remember to have been preſent, either to our internal perception or ſenſes; and every particular of that ſyſtem, join'd to the preſent im⯑preſſions, we are pleas'd to call a reality. But the mind ſtops not here. For finding, that with this ſyſtem of perceptions, there is another connected by cuſtom, or if you will, by the relation of cauſe or effect, it proceeds to the conſideration of their ideas; and as it feels that 'tis in a manner neceſſa⯑rily determin'd to view theſe particular ideas, and that the cuſtom or relation, by which it is determin'd, admits not of the leaſt change, it forms them into a new ſyſtem, which it likewiſe dignifies with the title of realities. The firſt of theſe ſyſtems is the [193] object of the memory and ſenſes; the ſe⯑cond of the judgment.

'TIS this latter principle, which peoples the world, and brings us acquainted with ſuch exiſtences, as by their removal in time and place, lie beyond the reach of the ſenſes and memory. By means of it I paint the univerſe in my imagination, and fix my at⯑tention on any part of it I pleaſe. I form an idea of ROME, which I neither ſee nor remember; but which is connected with ſuch impreſſions as I remember to have re⯑ceived from the converſation and books of travellers and hiſtorians. This idea of Rome I place in a certain ſituation on the idea of an object, which I call the globe. I join to it the conception of a particular govern⯑ment, and religion, and manners. I look backward and conſider its firſt foundation; its ſeveral revolutions, ſucceſſes, and misfor⯑tunes. All this, and every thing elſe, which I believe, are nothing but ideas; tho' by their force and ſettled order, ariſing from cuſtom and the relation of cauſe and effect, they diſtinguiſh themſelves from the other ideas, which are merely the offspring of the imagination.

AS to the influence of contiguity and reſemblance, we may obſerve, that if the [194] contiguous and reſembling object be com⯑prehended in this ſyſtem of realities, there is no doubt but theſe two relations will aſſiſt that of cauſe and effect, and in⯑fix the related idea with more force in the imagination. This I ſhall enlarge upon preſently. Mean while I ſhall carry my ob⯑ſervation a ſtep farther, and aſſert, that even where the related object is but feign'd, the relation will ſerve to enliven the idea, and encreaſe its influence. A poet, no doubt, will be the better able to form a ſtrong de⯑ſcription of the Elyſian fields, that he prompts his imagination by the view of a beautiful meadow or garden; as at another time he may by his fancy place himſelf in the midſt of theſe fabulous regions, that by the feign'd contiguity he may enliven his imagination.

BUT tho' I cannot altogether exclude the relations of reſemblance and contiguity from operating on the fancy in this manner, 'tis obſervable that, when ſingle, their in⯑fluence is very feeble and uncertain. As the relation of cauſe and effect is requiſite to perſuade us of any real exiſtence, ſo is this perſuaſion requiſite to give force to theſe o⯑ther relations. For where upon the appear⯑ance of an impreſſion we not only feign [195] another object, but likewiſe arbitrarily, and of our mere good-will and pleaſure give it a particular relation to the impreſſion, this can have but a ſmall effect upon the mind; nor is there any reaſon, why, upon the re⯑turn of the ſame impreſſion, we ſhou'd be determin'd to place the ſame object in the ſame relation to it. There is no manner of neceſſity for the mind to feign any reſem⯑bling and contiguous objects; and if it feigns ſuch, there is as little neceſſity for it always to confine itſelf to the ſame, without any difference or variation. And indeed ſuch a fiction is founded on ſo little reaſon, that nothing but pure caprice can determine the mind to form it; and that principle be⯑ing fluctuating and uncertain, 'tis impoſſi⯑ble it can ever operate with any conſidera⯑ble degree of force and conſtancy. The mind forſees and anticipates the change; and even from the very firſt inſtant feels the looſeneſs of its actions, and the weak hold it has of its objects. And as this imperfec⯑tion is very ſenſible in every ſingle inſtance, it ſtill encreaſes by experience and ob⯑ſervation, when we compare the ſeveral in⯑ſtances we may remember, and form a ge⯑neral rule againſt the repoſing any aſſurance in thoſe momentary glimpſes of light, which [196] ariſe in the imagination from a feign'd re⯑ſemblance and contiguity.

THE relation of cauſe and effect has all the oppoſite advantages. The objects it pre⯑ſents are fixt and unalterable. The impreſ⯑ſions of the memory never change in any conſiderable degree; and each impreſſion draws along with it a preciſe idea, which takes its place in the imagination, as ſome⯑thing ſolid and real, certain and invariable. The thought is always determin'd to paſs from the impreſſion to the idea, and from that particular impreſſion to that particu⯑lar idea, without any choice or heſitation.

BUT not content with removing this ob⯑jection, I ſhall endeavour to extract from it a proof of the preſent doctrine. Contigui⯑ty and reſemblance have an effect much in⯑ferior to cauſation; but ſtill have ſome ef⯑fect, and augment the conviction of any opinion, and the vivacity of any conception. If this can be prov'd in ſeveral new inſtances, beſide what we have already obſerv'd, 'twill be allow'd no inconſiderable argument, that belief is nothing but a lively idea related to a preſent impreſſion.

To begin with contiguity; it has been remark'd among the Mahometans as well as Chriſtians, that thoſe pilgrims, who have [197] ſeen MECCA or the HOLY LAND are ever after more faithful and zealous believers, than thoſe who have not had that advantage. A man, whoſe memory preſents him with a lively image of the Red-Sea, and the De⯑ſert, and Jeruſalem, and Galiee, can never doubt of any miraculous events, which are related either by Moſes or the Evangeliſts. The lively idea of the places paſſes by an eaſy tranſition to the facts, which are ſup⯑pos'd to have been related to them by con⯑tiguity, and encreaſes the belief by encrea⯑ſing the vivacity of the conception. The remembrance of theſe fields and rivers has the ſame influence on the vulgar as a new argument; and from the ſame cauſes.

WE may from a like obſervation con⯑cerning reſemblance. We have remark'd, that the concluſion, which we draw from a preſent object to its abſent cauſe or effect, is never founded on any qualities, which we obſerve in that object, conſider'd in it⯑ſelf; or, in other words, that 'its impoſſible to determine, otherwiſe than by experience, what will reſult from any phaenomenon, or what has preceded it. But tho' this be ſo evident in itſelf, that it ſeem'd not to require any proof; yet ſome philoſo⯑phers have imagin'd that there is an appa⯑rent [198] cauſe for the communication of mo⯑tion, and that a reaſonable man might im⯑mediately infer the motion of one body from the impulſe of another, without having re⯑courſe to any paſt obſervation. That this opinion is falſe will admit of an eaſy proof. For if ſuch an inference may be drawn mere⯑ly from the ideas of body, of motion, and of impulſe, it muſt amount to a demon⯑ſtration, and muſt imply the abſolute im⯑poſſibility of any contrary ſuppoſition. Eve⯑ry effect, then, beſide the communication of motion, implies a formal contradiction; and 'tis impoſſible not only that it can exiſt, but alſo that it can be conceiv'd. But we may ſoon ſatisfy ourſelves of the contrary, by forming a clear and conſiſtent idea of one body's moving upon another, and of its reſt immediately upon the contact; or of its re⯑turning back in the ſame line, in which it came; or of its annihilation; or circular or elliptical motion: and in ſhort, of an infinite number of other changes, which we may ſuppoſe it to undergo. Theſe ſuppoſitions are all conſiſtent and natural; and the rea⯑ſon, why we imagine the communication of motion to be more conſiſtent and natural not only than thoſe ſuppoſitions, but alſo than any other natural effect, is founded on [199] the relation of reſemblance betwixt the cauſe and effect, which is here united to experi⯑ence, and binds the objects in the cloſeſt and moſt intimate manner to each other, ſo as to make us imagine them to be abſolute⯑ly inſeparable. Reſemblance, then, has the ſame or a parallel influence with experience; and as the only immediate effect of expe⯑rience is to aſſociate our ideas together, it follows, that all belief ariſes from the aſſo⯑ciation of ideas, according to my hypotheſis.

'TIS univerſally allow'd by the writers on optics, that the eye at all times ſees an equal number of phyſical points, and that a man on the top of a mountain has no larger an image preſented to his ſenſes, than when he is coop'd up in the narroweſt court or cham⯑ber. 'Tis only by experience that he infers the greatneſs of the object from ſome pecu⯑liar qualities of the image; and this infe⯑rence of the judgment he confounds with ſenſation, as is common on other occaſions. Now 'tis evident, that the inference of the judgment is here much more lively than what is uſual in our common reaſonings, and that a man has a more vivid conception of the vaſt extent of the ocean from the image he receives by the eye, when he ſtands on the top of the high promontory, than mere⯑ly [200] from hearing the roaring of the waters. He feels a more ſenſible pleaſure from its magnificence; which is a proof of a more lively idea: And he confounds his judg⯑ment with ſenſation; which is another proof of it. But as the inference is equally cer⯑tain and immediate in both caſes, this ſupe⯑rior vivacity of our conception in one caſe can proceed from nothing but this, that in drawing an inference from the fight, be⯑ſide the cuſtomary conjunction, there is al⯑ſo a reſemblance betwixt the image and the object we infer; which ſtrengthens the re⯑lation, and conveys the vivacity of the im⯑preſſion to the related idea with an eaſier and more natural movement.

No weakneſs of human nature is more univerſal and conſpicuous than what we com⯑monly call CREDULITY, or a too eaſy faith in the teſtimony of others; and this weakneſs is alſo very naturally accounted for from the influence of reſemblance. When we receive any matter of fact upon human teſtimony, our faith ariſes from the very ſame origin as our inferences from cauſes to effects, and from effects to cauſes; nor is there any thing but our experience of the governing principles of human nature, which can give us any aſſurance of the veracity of [201] men. But tho' experience be the true ſtan⯑dard of this, as well as of all other judg⯑ments, we ſeldom regulate ourſelves entire⯑ly by it; but have a remarkable propenſity to believe whatever is reported, even con⯑cerning apparitions, enchantments, and pro⯑digies, however contrary to daily experience and obſervation. The words or diſcourſes of others have an intimate connexion with certain ideas in their mind; and theſe ideas have alſo a connexion with the facts or ob⯑jects, which they repreſent. This latter connexion is generally much over-rated, and commands our aſſent beyond what experi⯑ence will juſtify; which can proceed from nothing beſide the reſemblance betwixt the ideas and the facts. Other effects only point out their cauſes in an oblique manner; but the teſtimony of men does it directly, and is to be conſider'd as an image as well as an effect. No wonder, therefore, we are ſo raſh in drawing our inferences from it, and are leſs guided by experience in our judgments concerning it, that in thoſe up⯑on any other ſubject.

As reſemblance, when conjoin'd with cauſation, fortifies our reaſonings; ſo the want of it in any very great degree is able almoſt entirely to deſtroy them. Of [202] this there is a remarkable inſtance in the univerſal careleſſneſs and ſtupidity of men with regard to a future ſtate, where they ſhow as obſtinate an incredulity, as they do a blind credulity on other occaſions. There is not indeed a more ample matter of wonder to the ſtudious, and of regret to the pious man, than to obſerve the neg⯑ligence of the bulk of mankind concern⯑ing their approaching condition; and 'tis with reaſon, that many eminent theologians have not ſcrupled to affirm, that tho' the vulgar have no formal principles of infide⯑lity, yet they are really infidels in their hearts, and have nothing like what we can call a belief of the eternal duration of their ſouls. For let us conſider on the one hand what divines have diſplay'd with ſuch elo⯑quence concerning the importance of eter⯑nity; and at the ſame time reflect, that tho' in matters of rhetoric we ought to lay our account with ſome exaggeration, we muſt in this caſe allow, that the ſtrongeſt figures are infinitely inferior to the ſubject: And after this let us view on the other hand the prodigious ſecurity of men in this par⯑ticular: I aſk, if theſe people really believe what is inculcated on them, and what they pretend to affirm; and the anſwer is obvi⯑ouſly [203] in the negative. As belief is an act of the mind ariſing from cuſtom, 'tis not ſtrange the want of reſemblance ſhou'd over⯑throw what cuſtom has eſtabliſh'd, and di⯑miniſh the force of the idea, as much as that latter principle encreaſes it. A future ſtate is ſo far remov'd from our comprehenſion, and we have ſo obſcure an idea of the man⯑ner, in which we ſhall exiſt after the diſ⯑ſolution of the body, that all the reaſons we can invent, however ſtrong in them⯑ſelves, and however much aſſiſted by edu⯑cation, are never able with ſlow imaginations to ſurmount this difficulty, or beſtow a ſuf⯑ficient authority and force on the idea. I rather chooſe to aſcribe this incredulity to the faint idea we form of our future condi⯑tion, deriv'd from its want of reſemblance to the preſent life, than to that deriv'd from its remoteneſs. For I obſerve, that men are every where concern'd about what may happen after their death, provided it regard this world; and that there are few to whom their name, their family, their friends, and their country are in any period of time en⯑tirely indifferent.

AND indeed the want of reſemblance in this caſe ſo entirely deſtroys belief, that ex⯑cept thoſe few, who upon cool reflection on [204] the importance of the ſubject, have taken care by repeated meditation to imprint in their minds the arguments for a future ſtate, there ſcarce are any, who believe the im⯑mortality of the ſoul with a true and eſtab⯑liſh'd judgment; ſuch as is deriv'd from the teſtimony of travellers and hiſtorians. This appears very conſpicuouſly wherever men have occaſion to compare the pleaſures and pains, the rewards and puniſhments of this life with thoſe of a future; even tho' the caſe does not concern themſelves, and there is no violent paſſion to diſturb their judg⯑ment. The Roman Catholicks are certainly the moſt zealous of any ſect in the chriſtian world; and yet you'll find few among the more ſenſible people of that communion, who do not blame the Gunpowder-treaſon, and the maſſacre of St. Bartholemew, as cruel and barbarous, tho' projected or executed againſt thoſe very people, whom without any ſcruple they condemn to eternal and infinite puniſhments. All we can ſay in ex⯑cuſe for this inconſiſtency is, that they really do not believe what they affirm concerning a future ſtate; nor is there any better proof of it than the very inconſiſtency.

WE may add to this a remark; that in matters of religion men take a pleaſure in [205] being terrify'd, and that no preachers are ſo popular, as thoſe who excite the moſt diſ⯑mal and gloomy paſſions. In the common affairs of life, where we feel and are pene⯑trated with the ſolidity of the ſubject, no⯑thing can be more diſagreeable than fear and terror; and 'tis only in dramatic perfor⯑mances and in religious diſcourſes, that they ever give pleaſure. In theſe latter caſes the imagination repoſes itſelf indolently on the idea; and the paſſion, being ſoften'd by the want of belief in the ſubject, has no more than the agreeable effect of enlivening the mind, and fixing the attention.

THE preſent hypotheſis will receive additi⯑onal confirmation, if we examine the effects of other kinds of cuſtom, as well as of other relations. To underſtand this we muſt con⯑ſider, that cuſtom, to which I attribute all belief and reaſoning, may operate upon the mind in invigorating an idea after two ſe⯑veral ways. For ſuppoſing that in all paſt experience we have found two objects to have been always conjoin'd together, 'tis evident, that upon the appearance of one of theſe objects in an impreſſion, we muſt from cuſ⯑tom make an eaſy tranſition to the idea of that object, which uſually attends it; and by means of the preſent impreſſion and eaſy [206] tranſition muſt conceive that idea in a ſtronger and more lively manner, than we do any looſe floating image of the fancy. But let us next ſuppoſe, that a mere idea alone, without any of this curious and almoſt ar⯑tificial preparation, ſhou'd frequently make its appearance in the mind, this idea muſt by degrees acquire a facility and force; and both by its firm hold and eaſy introduction diſtinguiſh itſelf from any new and unuſual idea. This is the only particular, in which theſe two kinds of cuſtom agree; and if it appear, that their effects on the judgment are ſimilar and proportionable, we may cer⯑tainly conclude, that the foregoing explica⯑tion of that faculty is ſatisfactory. But can we doubt of this agreement in their influence on the judgment, when we conſider the na⯑ture and effects of EDUCATION?

ALL thoſe opinions and notions of things, to which we have been accuſtom'd from our infancy, take ſuch deep root, that 'tis impoſſible for us, by all the powers of rea⯑ſon and experience, to eradicate them; and this habit not only approaches in its influ⯑ence, but even on many occaſions prevails over that which ariſes from the conſtant and inſeparable union of cauſes and effects. Here we muſt not be contented with ſaying, that [207] the vividneſs of the idea produces the belief: We muſt maintain that they are individu⯑ally the ſame. The frequent repetition of any idea infixes it in the imagination; but cou'd never poſſibly of itſelf produce belief, if that act of the mind was, by the original conſtitution of our natures, annex'd only to a reaſoning and compariſon of ideas. Cuſ⯑tom may lead us into ſome falſe compa⯑riſon of ideas. This is the utmoſt effect we can conceive of it. But 'tis certain it cou'd never ſupply the place of that compariſon, nor produce any act of the mind, which naturally belong'd to that principle.

A PERSON, that has loſt a leg or an arm by amputation, endeavours for a long time afterwards to ſerve himſelf with them. After the death of any one, 'tis a common remark of the whole family, but eſpecially of the ſervants, that they can ſcarce believe him to be dead, but ſtill imagine him to be in his chamber or in any other place, where they were accuſtom'd to find him. I have often heard in converſation, after talking of a perſon, that is any way cele⯑brated, that one, who has no acquaintance with him, will ſay, I have never ſeen ſuch-a⯑one, but almoſt fancy I have; ſo often have I [208] heard talk of him. All theſe are parallel in⯑ſtances.

IF we conſider this argument from edu⯑cation in a proper light, 'twill appear very con⯑vincing; and the more ſo, that 'tis founded on one of the moſt common phaenomena, that is any where to be met with. I am perſuaded, that upon examination we ſhall find more than one half of thoſe opinions, that prevail among mankind, to be owing to education, and that the principles, which are thus implicitely embrac'd, over-ballance thoſe, which are owing either to abſtract reaſoning or experience. As liars, by the frequent repetition of their lies, come at laſt to remember them; ſo the judgment, or rather the imagination, by the like means, may have ideas ſo ſtrongly imprinted on it, and conceive them in ſo full a light, that they may operate upon the mind in the ſame manner with thoſe, which the ſenſes, memory or reaſon preſent to us. But as education is an artificial and not a natural cauſe, and as its maxims are frequently con⯑trary to reaſon, and even to themſelves in different times and places, it is never upon that account recogniz'd by philoſophers; tho' in reality it be built almoſt on the ſame foundation of cuſtom and repetition [209] as our reaſonings from cauſes and effects.^*.

SECT. X. Of the influence of belief.

BUT tho' education be diſclaim'd by philoſophy, as a fallacious ground of aſſent to any opinion, it prevails nevertheleſs in the world, and is the cauſe why all ſyſ⯑tems are apt to be rejected at firſt as new and unuſual. This perhaps will be the fate of what I have here advanc'd concerning belief, and tho' the proofs I have produc'd appear to me perfectly concluſive, I expect not to make many proſelytes to my opi⯑nion. Men will ſcarce ever be perſuaded, that effects of ſuch conſequence can flow from principles, which are ſeemingly ſo inconſi⯑derable, and that the far greateſt part of our reaſonings with all our actions and paſſions, [210] can be deriv'd from nothing but cuſtom and habit. To obviate this objection, I ſhall here anticipate a little what wou'd more properly fall under our conſideration afterwards, when we come to treat of the paſſions and the ſenſe of beauty.

THERE is implanted in the human mind a perception of pain and pleaſure, as the chief ſpring and moving principle of all its actions. But pain and pleaſure have two ways of mak⯑ing their appearance in the mind; of which the one has effects very different from the other. They may either appear in impreſſion to the actual feeling, or only in idea, as at preſent when I mention them. 'Tis evident the influ⯑ence of theſe upon actions is far from being equal. Impreſſions always actuate the ſoul, and that in the higheſt degree; but 'tis not every idea which has the ſame effect. Na⯑ture has proceeded with caution in this caſe, and ſeems to have carefully avoided the in⯑conveniences of two extremes. Did impreſ⯑ſions alone influence the will, we ſhould every moment of our lives be ſubject to the greateſt calamities; becauſe, tho' we foreſaw their approach, we ſhould not be provided by nature with any principle of action, which might impel us to avoid them. On the other hand, did every idea influence our actions, [211] our condition would not be much mended. For ſuch is the unſteadineſs and activity of thought, that the images of every thing, eſpecially of goods and evils, are always wandering in the mind; and were it mov'd by every idle conception of this kind, it would never enjoy a moment's peace and tranquillity.

NATURE has, therefore, choſen a me⯑dium, and has neither beſtow'd on every idea of good and evil the power of actuating the will, nor yet has entirely excluded them from this influence. Tho' an idle fiction has no efficacy, yet we find by experience, that the ideas of thoſe objects, which we believe either are or will be exiſtent, produce in a leſſer degree the ſame effect with thoſe im⯑preſſions, which are immediately preſent to the ſenſes and perception. The effect, then, of belief is to raiſe up a ſimple idea to an equality with our impreſſions, and beſtow on it a like influence on the paſſions. This effect it can only have by making an idea approach an impreſion in force and vivacity. For as the different degrees of force make all the original difference betwixt an impreſſion and an idea, they muſt of conſequence be the ſource of all the differences in the effects of theſe perceptions, and their removal, in whole [212] or in part, the cauſe of every new reſemblance they acquire. Wherever we can make an idea approach the impreſſions in force and vivacity, it will likewiſe imitate them in its influence on the mind; and vice verſa, where it imi⯑tates them in that influence, as in the pre⯑ſent caſe, this muſt proceed from its ap⯑proaching them in force and vivacity. Be⯑lief, therefore, ſince it cauſes an idea to imi⯑tate the effects of the impreſſions, muſt make it reſemble them in theſe qualities, and is nothing but a more vivid and intenſe concep⯑tion of any idea. This, then, may both ſerve as an additional argument for the preſent ſyſ⯑tem, and may give us a notion after what manner our reaſonings from cauſation are able to operate on the will and paſſions.

As belief is almoſt abſolutely requiſite to the exciting our paſſions, ſo the paſſions in their turn are very favourable to belief; and not only ſuch facts as convey agreeable emo⯑tions, but very often ſuch as give pain, do upon that account become more readily the objects of faith and opinion. A coward, whoſe fears are eaſily awaken'd, readily aſ⯑ſents to every account of danger he meets with; as a perſon of a ſorrowful and melan⯑choly diſpoſition is very credulous of every thing, that nouriſhes his prevailing paſſion. [213] When any affecting object is preſented, it gives the alarm, and excites immediately degree of its proper paſſion; eſpecially in perſons who are naturally inclined to that paſſion. This emotion paſſes by an eaſy tranſition to the imagination; and diffuſing itſelf over our idea of the affecting object, makes us form that idea with greater force and vivacity, and conſequently aſſent to it, according to the precedent ſyſtem. Admi⯑ration and ſurprize have the ſame effect as the other paſſions; and accordingly we may obſerve, that among the vulgar, quacks and projectors meet with a more eaſy faith upon account of their magnificent pretenſions, than if they kept themſelves within the bounds of moderation. The firſt aſtoniſhment, which naturally attends their miraculous relations, ſpreads itſelf over the whole ſoul, and ſo vi⯑vifies and enlivens the idea, that it reſembles the inferences we draw from experience. This is a myſtery, with which we may be alrea⯑dy a little acquainted, and which we ſhall have farther occaſion to be let into in the progreſs of this treatiſe.

AFTER this account of the influence of belief on the paſſions, we ſhall find leſs difficulty in explaining its effects on the imagination, however extraordinary they [214] may appear. 'Tis certain we cannot take pleaſure in any diſcourſe, where our judg⯑ment gives no aſſent to thoſe images which are preſented to our fancy. The converſa⯑tion of thoſe, who have acquir'd a habit of lying, tho' in affairs of no moment, never gives any ſatisfaction; and that becauſe thoſe ideas they preſent to us, not being attended with belief, make no impreſſion upon the mind. Poets themſelves, tho' liars by pro⯑feſſion, always endeavour to give an air of truth to their fictions; and where that is to⯑tally neglected, their performances, however ingenious, will never be able to afford much pleaſure. In ſhort, we may obſerve, that even when ideas have no manner of influence on the will and paſſions, truth and reality are ſtill requiſite, in order to make them en⯑tertaining to the imagination.

BUT if we compare together all the phae⯑nomena that occur on this head, we ſhall find, that truth, however neceſſary it may ſeem in all works of genius, has no other effect than to procure an eaſy reception for the ideas, and to make the mind acquieſce in them with ſatisfaction, or at leaſt without reluctance. But as this is an effect, which may eaſily be ſuppoſed to flow from that ſo⯑lidity [215] and force, which, according to my ſyſtem, attend thoſe ideas that are eſtabliſh'd by reaſonings from cauſation; it follows, that all the influence of belief upon the fancy may be explained from that ſyſtem. Ac⯑cordingly we may obſerve, that wherever that influence ariſes from any other principles be⯑ſide truth or reality, they ſupply its place, and give an equal entertainment to the ima⯑gination. Poets have form'd what they call a poetical ſyſtem of things, which tho' it be believ'd neither by themſelves nor readers, is commonly eſteem'd a ſufficient foundation for any fiction. We have been ſo much accuſtom'd to the names of MARS, JUPITER, VENUS, that in the ſame manner as education infixes any opinion, the conſtant repetition of theſe ideas makes them enter into the mind with facility, and prevail upon the fancy, without influencing the judgment. In like manner tragedians always borrow their fable, or at leaſt the names of their principal actors, from ſome known paſſage in hiſtory; and that not in order to deceive the ſpectators; for they will frankly confeſs, that truth is not in any circumſtance inviolably obſerved; but in or⯑der to procure a more eaſy reception into the imagination for thoſe extraordinary events, which they repreſent. But this is a precau⯑tion, [216] which is not required of comic poets, whoſe perſonages and incidents, being of a more familiar kind, enter eaſily into the con⯑ception, and are received without any ſuch formality, even tho' at firſt ſight they be known to be fictitious, and the pure off⯑ſpring of the fancy.

THIS mixture of truth and falſhood in the fables of tragic poets not only ſerves our preſent purpoſe, by ſhewing, that the ima⯑gination can be ſatisfy'd without any abſolute belief or aſſurance; but may in another view be regarded as a very ſtrong confirmation of this ſyſtem. 'Tis evident, that poets make uſe of this artifice of borrowing the names of their perſons, and the chief events of their poems, from hiſtory, in order to procure a more eaſy reception for the whole, and cauſe it to make a deeper impreſſion on the fancy and affections. The ſeveral incidents of the piece acquire a kind of relation by being uni⯑ted into one poem or repreſentation; and if any of theſe incidents be an object of belief, it beſtows a force and vivacity on the others, which are related to it. The vividneſs of the firſt conception diffuſes itſelf along the relations, and is convey'd, as by ſo many pipes or canals, to every idea that has any communication with the primary one. This, [217] indeed, can never amount to a perfect aſſur⯑rance; and that becauſe the union among the ideas is, in a manner, accidental: But ſtill it approaches ſo near, in its influence, as may convince us, that they are deriv'd from the ſame origin. Belief muſt pleaſe the imagination by means of the force and vivacity which attends it; ſince every idea, which has force and vivacity, is found to be agreeable to that faculty.

To confirm this we may obſerve, that the aſſiſtance is mutual betwixt the judgment and fancy, as well as betwixt the judgment and paſſion; and that belief not only gives vigour to the imagination, but that a vigorous and ſtrong imagination is of all talents the moſt proper to procure belief and authority. 'Tis difficult for us to withold our aſſent from what is painted out to us in all the co⯑lours of eloquence; and the vivacity pro⯑duc'd by the fancy is in many caſes greater than that which ariſes from cuſtom and expe⯑rience. We are hurried away by the lively imagination of our author or companion; and even he himſelf is often a victim to his own fire and genius.

NOR will it be amiſs to remark, that as a lively imagination very often degenerates into madneſs or folly, and bears it a great [218] reſemblance in its operations; ſo they in⯑fluence the judgment after the ſame manner, and produce belief from the very ſame prin⯑ciples. When the imagination, from any extraordinary ferment of the blood and ſpi⯑rits, acquires ſuch a vivacity as diſorders all its powers and faculties, there is no means of diſtinguiſhing betwixt truth and falſhood; but every looſe fiction or idea, having the ſame influence as the impreſſions of the me⯑mory, or the concluſions of the judgment, is receiv'd on the ſame footing, and operates with equal force on the paſſions. A preſent impreſſion and a cuſtomary tranſition are now no longer neceſſary to inliven our ideas. Eve⯑ry chimera of the brain is as vivid and in⯑tenſe as any of thoſe inferences, which we formerly dignify'd with the name of con⯑cluſions concerning matters of fact, and ſometimes as the preſent impreſſions of the ſenſes.

WE may obſerve the ſame effect of poetry in a leſſer degree; only with this difference, that the leaſt reflection diſſipates the illuſions of poetry, and places the objects in their proper light. 'Tis however certain, that in the warmth of a poetical enthuſiaſm, a poet has a counterfeit belief, and even a kind of viſion of his objects: And if there be any [219] ſhadow of argument to ſupport this belief, nothing contributes more to his full con⯑viction than a blaze of poetical figures and images, which have their effect upon the poet himſelf, as well as upon his readers.

SECT. XI. Of the probability of chances.

BUT in order to beſtow on this ſyſtem its full force and evidence, we muſt carry our eye from it a moment to conſider its conſequences, and explain from the ſame principles ſome other ſpecies of reaſoning, which are deriv'd from the ſame origin.

THOSE philoſophers, who have divided human reaſon into knowledge and probability, and have defin'd the firſt to be that evi⯑dence, which ariſes from the compariſon of ideas, are oblig'd to comprehend all our ar⯑guments from cauſes or effects under the general term of probability. But tho' every one be free to uſe his terms in what ſenſe he pleaſes; and accordingly in the precedent part of this diſcourſe, I have follow'd this method of expreſſion; 'tis however certain, that in common diſcourſe we readily affirm, [220] that many arguments from cauſation exceed probability, and may be receiv'd as a ſupe⯑rior kind of evidence. One wou'd appear ridiculous, who wou'd ſay, that 'tis only probable the ſun will riſe to-morrow, or that all men muſt dye; tho' 'tis plain we have no further aſſurance of theſe facts, than what experience affords us. For this reaſon, 'twould perhaps be more convenient, in order at once to preſerve the common ſignification of words, and mark the ſeveral degrees of evidence, to diſtinguiſh human reaſon into three kinds, viz. that from knowledge, from proofs, and from probabili⯑ties. By knowledge, I mean the aſſurance ariſing from the compariſon of ideas. By proofs, thoſe arguments, which are deriv'd from the relation of cauſe and effect, and which are entirely free from doubt and un⯑certainty. By probability, that evidence, which is ſtill attended with uncertainty. 'Tis this laſt ſpecies of reaſoning, I proceed to examine.

PROBABILITY or reaſoning from con⯑jecture may be divided into two kinds, viz. that which is founded on chance, and that which ariſes from cauſes. We ſhall conſi⯑der each of theſe in order.

THE idea of cauſe and effect is deriv'd [221] from experience, which preſenting us with certain objects conſtantly conjoin'd with each other, produces ſuch a habit of ſurveying them in that relation, that we cannot with⯑out a ſenſible violence ſurvey them in any other. On the other hand, as chance is no⯑thing real in itſelf, and properly, ſpeaking, is merely the negation of a cauſe, its influence on the mind is contrary to that of cauſa⯑tion; and 'tis eſſential to it, to leave the imagination perfectly indifferent, either to conſider the exiſtence or non-exiſtence of that object, which is regarded as contingent. A cauſe traces the way to our thought, and in a manner forces us to ſurvey ſuch cer⯑tain objects, in ſuch certain relations. Chance can only deſtroy this determination of the thought, and leave the mind in its native ſituation of indifference; in which, upon the abſence of a cauſe, 'tis inſtantly re-inſtated.

SINCE therefore an entire indifference is eſſential to chance, no one chance can poſſibly be ſuperior to another, otherwiſe than as it is compos'd of a ſuperior number of equal chances. For if we affirm that one chance can, after any other manner, be ſuperior to another, we muſt at the ſame time affirm, that there is ſomething, which gives it the [222] ſuperiority, and determines the event rather to that ſide than the other: That is, in o⯑ther words, we muſt allow of a cauſe, and deſtroy the ſuppoſition of chance; which we had before eſtabliſh'd. A perfect and total indifference is eſſential to chance, and one total indifference can never in itſelf be either ſuperior or inferior to another. This truth is not peculiar to my ſyſtem, but is acknowledg'd by every one, that forms cal⯑culations concerning chances.

AND here 'tis remarkable, that tho' chance and cauſation be directly contrary, yet 'tis impoſſible for us to conceive this combination of chances, which is requiſite to render one hazard ſuperior to another, without ſuppoſing a mixture of cauſes a⯑mong the chances, and a conjunction of neceſſity in ſome particulars, with a total indifference in others. Where nothing li⯑mits the chances, every notion, that the moſt extravagant fancy can form, is upon a footing of equality; nor can there be any circumſtance to give one the advantage a⯑bove another. Thus unleſs we allow, that there are ſome cauſes to make the dice fall, and preſerve their form in their fall, and lie upon ſome one of their ſides, we can form no calculation concerning the laws of ha⯑zard. [223] But ſuppoſing theſe cauſes to ope⯑rate, and ſuppoſing likewiſe all the reſt to be indifferent and to be determin'd by chance, 'tis eaſy to arrive at a notion of a ſuperior combination of chances. A dye, that has four ſides mark'd with a certain number of ſpots, and only two with ano⯑ther, affords us an obvious and eaſy inſtance of this ſuperiority. The mind is here li⯑mited by the cauſes to ſuch a preciſe num⯑ber and quality of the events; and at the ſame time is undetermin'd in its choice of any particular event.

PROCEEDING then in that reaſoning, wherein we have advanc'd three ſteps; that chance is merely the negation of a cauſe, and produces a total indifference in the mind; that one negation of a cauſe and one total indifference can never be ſuperior or inferior to another; and that there muſt always be a mixture of cauſes among the chances, in order to be the foundation of any reaſoning: We are next to conſider what effect a ſuperior combination of chances can have upon the mind, and after what man⯑ner it influences our judgment and opinion. Here we may repeat all the ſame arguments we employ'd in examining that belief, which ariſes from cauſes; and may prove after the [224] ſame manner, that a ſuperior number of chances produces our aſſent neither by de⯑monſtration nor probability. 'Tis indeed e⯑vident, that we can never by the compari⯑ſon of mere ideas make any diſcovery, which can be of conſequence in this affair, and that 'tis impoſſible to prove with cer⯑tainty, that any event muſt fall on that ſide where there is a ſuperior number of chances. To ſuppoſe in this caſe any certainty, were to overthrow what we have eſtabliſh'd con⯑cerning the oppoſition of chances, and their perfect equality and indifference.

SHOU'D it be ſaid, that tho' in an oppo⯑ſition of chances 'tis impoſſible to determine with certainty, on which ſide the event will fall, yet we can pronounce with certainty, that 'tis more likely and probable, 'twill be on that ſide where there is a ſuperior num⯑ber of chances, than where there is an in⯑ferior: Shou'd this be ſaid, I wou'd aſk, what is here meant by likelihood and pro⯑bability? The likelihood and probability of chances is a ſuperior number of equal chan⯑ces; and conſequently when we ſay 'tis likely the event will fall on the ſide, which is ſuperior, rather than on the inferior, we do no more than affirm, that where there is a ſuperior number of chances there is ac⯑actually [225] a ſuperior, and where there is an inferior there is an inferior; which are iden⯑tical propoſitions, and of no conſequence. The queſtion is, by what means a ſuperior number of equal chances operates upon the mind, and produces belief or aſſent; ſince it appears, that 'tis neither by arguments deriv'd from demonſtration, nor from pro⯑bability.

IN order to clear up this difficulty, we ſhall ſuppoſe a perſon to take a dye, form'd after ſuch a manner as that four of its ſides are mark'd with one figure, or one number of ſpots, and two with another; and to put this dye into the box with an intention of throwing it: 'Tis plain, he muſt conclude the one figure to be more probable than the other, and give the preference to that which is in⯑ſcrib'd on the greateſt number of ſides. He in a manner believes, that this will lie up⯑permoſt; tho' ſtill with heſitation and doubt, in proportion to the number of chances, which are contrary: And according as theſe contrary chances diminiſh, and the ſuperio⯑rity encreaſes on the other ſide, his belief acquires new degrees of ſtability and aſſu⯑rance. This belief ariſes from an operation of the mind upon the ſimple and limited object before us; and therefore its nature [226] will be the more eaſily diſcover'd and ex⯑plain'd. We have nothing but one ſingle dye to contemplate, in order to comprehend one of the moſt curious operations of the underſtanding.

THIS dye form'd as above, contains three circumſtances worthy of our attention. Firſt, Certain cauſes, ſuch as gravity, ſolidity, a cubical figure, &c. which determine it to fall, to preſerve its form in its fall, and to turn up one of its ſides. Secondly, A certain number of ſides, which are ſuppos'd indif⯑ferent. Thirdly, A certain figure, inſcrib'd on each ſide. Theſe three particulars form the whole nature of the dye, ſo far as re⯑lates to our preſent purpoſe; and conſe⯑quently are the only circumſtances regarded by the mind in its forming a judgment con⯑cerning the reſult of ſuch a throw. Let us, therefore, conſider gradually and carefully what muſt be the influence of theſe circum⯑ſtances on the thought and imagination.

FIRST, We have already obſerv'd, that the mind is determin'd by cuſtom to paſs from any cauſe to its effect, and that upon the appearance of the one, 'tis almoſt im⯑poſſible for it not to form an idea of the other. Their conſtant conjunction in paſt inſtances has produc'd ſuch a habit in the [227] mind, that it always conjoins them in its thought, and infers the exiſtence of the one from that of its uſual attendant. When it conſiders the dye as no longer ſupported by the box, it cannot without violence regard it as ſuſpended in the air; but naturally places it on the table, and views it as turn⯑ing up one of its ſides. This is the effect of the intermingled cauſes, which are re⯑quiſite to our forming any calculation con⯑cerning chances.

SECONDLY, 'Tis ſuppos'd, that tho' the dye be neceſſarily determin'd to fall, and turn up one of its ſides, yet there is nothing to fix the particular ſide, but that this is determin'd entirely by chance. The very nature and eſſence of chance is a negation of cauſes, and the leaving the mind in a perfect indifference among thoſe events, which are ſuppos'd contingent. When there⯑fore the thought is determin'd by the cauſes to conſider the dye as falling and turning up one of its ſides, the chances preſent all theſe ſides as equal, and make us conſider every one of them, one after another, as alike probable and poſſible. The imagina⯑tion paſſes from the cauſe, viz. the throw⯑ing of the dye, to the effect, viz. the turning up one of the ſix ſides; and feels a [228] kind of impoſſibility both of ſtopping ſhort in the way, and of forming any other idea. But as all theſe ſix ſides are incompatible, and the dye cannot turn up above one at once, this principle directs us not to con⯑ſider all of them at once as lying upper⯑moſt; which we look upon as impoſſible: Neither does it direct us with its entire force to any particular ſide; for in that caſe this ſide wou'd be conſider'd as certain and in⯑evitable; but it directs us to the whole ſix ſides after ſuch a manner as to divide its force equally among them. We conclude in general, that ſome one of them muſt re⯑ſult from the throw: We run all of them over in our minds: The determination of the thought is common to all; but no more of its force falls to the ſhare of any one, than what is ſuitable to its proportion with the reſt. 'Tis after this manner the origi⯑nal impulſe, and conſequently the vivacity of thought, ariſing from the cauſes, is di⯑vided and ſplit in pieces by the intermingled chances.

WE have already ſeen the influence of the two firſt qualities of the dye, viz. the cauſes, and the number and indifference of the ſides, and have learn'd how they give an impulſe to the thought, and divide that [229] impulſe into as many parts as there are u⯑nites in the number of ſides. We muſt now conſider the effects of the third particular, viz. the figures inſcrib'd on each ſide. 'Tis evident that where ſeveral ſides have the ſame figure inſcrib'd on them, they muſt concur in their influence on the mind, and muſt unite upon one image or idea of a fi⯑gure all thoſe divided impulſes, that were diſpers'd over the ſeveral ſides, upon which that figure is inſcrib'd. Were the queſtion only what ſide will be turn'd up, theſe are all perfectly equal, and no one cou'd ever have any advantage above another. But as the queſtion is concerning the figure, and as the ſame figure is preſented by more than one ſide; 'tis evident, that the impulſes be⯑longing to all theſe ſides muſt re-unite in that one figure, and become ſtronger and more forcible by the union. Four ſides are ſuppos'd in the preſent caſe to have the ſame figure inſcrib'd on them, and two to have another figure. The impulſes of the former are, therefore, ſuperior to thoſe of the latter. But as the events are contrary, and 'tis im⯑poſſible both theſe figures can be turn'd up; the impulſes likewiſe become contrary, and the inferior deſtroys the ſuperior, as far as its ſtrength goes. The vivacity of the idea [230] is always proportionable to the degrees of the impulſe or tendency to the tranſition; and belief is the ſame with the vivacity of the idea, according to the precedent doc⯑trine.

SECT. XII. Of the probability of cauſes.

WHAT I have ſaid concerning the probability of chances can ſerve to no other purpoſe, than to aſſiſt us in ex⯑plaining the probability of cauſes; ſince 'tis commonly allow'd by philoſophers, that what the vulgar call chance is nothing but a ſecret and conceal'd cauſe. That ſpecies of probability, therefore, is what we muſt chiefly examine.

THE probabilities of cauſes are of ſeveral kinds; but are all deriv'd from the ſame origin, viz. the aſſociation of ideas to a pre⯑ſent impreſſion. As the habit, which pro⯑duces the aſſociation, ariſes from the frequent conjunction of objects, it muſt arrive at its perfection by degrees, and muſt acquire new force from each inſtance, that falls under our obſervation. The firſt inſtance has lit⯑tle or no force: The ſecond makes ſome [231] addition to it: The third becomes ſtill more ſenſible; and 'tis by theſe ſlow ſteps, that our judgment arrives at a full aſſurance. But before it attains this pitch of perfection, it paſſes thro' ſeveral inferior degrees, and in all of them is only to be eſteem'd a pre⯑ſumption or probability. The gradation, therefore, from probabilities to proofs is in many caſes inſenſible; and the difference be⯑twixt theſe kinds of evidence is more eaſily perceiv'd in the remote degrees, than in the near and contiguous.

'TIS worthy of remark on this occaſion, that tho' the ſpecies of probability here ex⯑plain'd be the firſt in order, and naturally takes place before any entire proof can ex⯑iſt, yet no one, who is arriv'd at the age of maturity, can any longer be acquainted with it. 'Tis true, nothing is more common than for people of the moſt advanc'd know⯑ledge to have attain'd only an imperfect expe⯑rience of many particular events; which na⯑turally produces only an imperfect habit and tranſition: But then we muſt conſider, that the mind, having form'd another ob⯑ſervation concerning the connexion of cauſes and effects, gives new force to its reaſoning from that obſervation; and by means of it can build an argument on one ſingle [232] experiment, when duly prepar'd and ex⯑amin'd. What we have found once to fol⯑low from any object, we conclude will for ever follow from it; and if this maxim be not always built upon as certain, 'tis not for want of a ſufficient number of experiments, but becauſe we frequently meet with inſtances to the contrary; which leads us to the ſecond ſpecies of probability, where there is a contra⯑riety in our experience and obſervation.

'TWOU'D be very happy for men in the conduct of their lives and actions, were the ſame objects always conjoin'd together, and we had nothing to fear but the miſtakes of our own judgment, without having any reaſon to apprehend the uncertainty of na⯑ture. But as 'tis frequently found, that one obſervation is contrary to another, and that cauſes and effects follow not in the ſame order, of which we have had expe⯑rience, we are oblig'd to vary our reaſoning on account of this uncertainty, and take into conſideration the contrariety of events. The firſt queſtion, that occurs on this head, is concerning the nature and cauſes of the contrariety.

THE vulgar, who take things according to their firſt appearance, attribute the un⯑certainty of events to ſuch an uncertainty in [233] the cauſes, as makes them often fail of their uſual influence, tho' they meet with no ob⯑ſtacle nor impediment in their operation. But philoſophers obſerving, that almoſt in every part of nature there is contain'd a vaſt variety of ſprings and principles, which are hid, by reaſon of their minuteneſs or re⯑moteneſs, find that 'tis at leaſt poſſible the contrariety of events may not proceed from any contingency in the cauſe, but from the ſecret operation of contrary cauſes. This poſſibility is converted into certainty by far⯑ther obſervation, when they remark, that upon an exact ſcrutiny, a contrariety of ef⯑fects always betrays a contrariety of cauſes, and proceeds from their mutual hindrance and oppoſition. A peaſant can give no bet⯑ter reaſon for the ſtopping of any clock or watch than to ſay, that commonly it does not go right: But an artizan eaſily perceives, that the ſame force in the ſpring or pendu⯑lum has always the ſame influence on the wheels; but fails of its uſual effect, perhaps by reaſon of a grain of duſt, which puts a ſtop to the whole movement. From the obſervation of ſeveral parallel inſtances, phi⯑loſophers form a maxim, that the connexion betwixt all cauſes and effects is equally ne⯑ceſſary, and that its ſeeming uncertainty in [234] ſome inſtances proceeds from the ſecret op⯑poſition of contrary cauſes.

BUT however philoſophers and the vulgar may differ in their explication of the con⯑trariety of events, their inferences from it are always of the ſame kind, and founded on the ſame principles. A contrariety of events in the paſt may give us a kind of heſitating belief for the future after two ſe⯑veral ways. Firſt, By producing an im⯑perfect habit and tranſition from the preſent impreſſion to the related idea. When the conjunction of any two objects is frequent, without being entirely conſtant, the mind is determin'd to paſs from one object to the other; but not with ſo entire a habit, as when the union is uninterrupted, and all the inſtances we have ever met with are uniform and of a piece. We find from com⯑mon experience, in our actions as well as reaſonings, that a conſtant perſeverance in any courſe of life produces a ſtrong inclination and tendency to continue for the future; tho' there are habits of inferior degrees of force, proportion'd to the inferior degrees of ſteadineſs and uniformity in our conduct.

THERE is no doubt but this principle ſometimes takes place, and produces thoſe inferences we draw from contrary phaeno⯑mena; [235] tho' I am perſwaded, that upon ex⯑amination we ſhall not find it to be the principle, that moſt commonly influences the mind in this ſpecies of reaſoning. When we follow only the habitual determination of the mind, we make the tranſition with⯑out any reflection, and interpoſe not a mo⯑ments delay betwixt the view of one object and the belief of that, which is often found to attend it. As the cuſtom depends not upon any deliberation, it operates immediately, without allowing any time for reflection. But this method of proceeding we have but few inſtances of in our probable reaſonings; and even fewer than in thoſe, which are deriv'd from the uninterupted conjunction of objects. In the former ſpecies of reaſoning we commonly take knowingly into conſi⯑deration the contrariety of paſt events; we compare the different ſides of the contra⯑riety, and carefully weigh the experiments, which we have on each ſide: Whence we may conclude, that our reaſonings of this kind ariſe not directly from the habit, but in an oblique manner; which we muſt now endeavour to explain.

'TIS evident, that when an object is at⯑tended with contrary effects, we judge of them only by our paſt experience, and al⯑ways [236] conſider thoſe as poſſible, which we have obſerv'd to follow from it. And as paſt experience regulates our judgment con⯑cerning the poſſibility of theſe effects, ſo it does that concerning their probability; and that effect, which has been the moſt com⯑mon, we always eſteem the moſt likely. Here then are two things to be conſider'd, viz. the reaſons which determine us to make the paſt a ſtandard for the future, and the manner how we extract a ſingle judgment from a contrariety of paſt events.

FIRST we may obſerve, that the ſup⯑poſition, that the future reſembles the paſt, is not founded on arguments of any kind, but is deriv'd entirely from habit, by which we are determin'd to expect for the future the ſame train of objects, to which we have been accuſtom'd. This habit or determina⯑tion to transfer the paſt to the future is full and perfect; and conſequently the firſt im⯑pulſe of the imagination in this ſpecies of reaſoning is endow'd with the ſame qua⯑lities.

BUT, ſecondly, when in conſidering paſt experiments we find them of a contrary na⯑ture, this determination, tho' full and per⯑fect in itſelf, preſents us with no ſteady object, but offers us a number of diſagreeing [237] images in a certain order and proportion. The firſt impulſe, therefore, is here broke into pieces, and diffuſes itſelf over all thoſe images, of which each partakes an equal ſhare of that force and vivacity, that is de⯑riv'd from the impulſe. Any of theſe paſt events may again happen; and we judge, that when they do happen, they will be mix'd in the ſame proportion as in the paſt.

IF our intention, therefore, be to conſi⯑der the proportions of contrary events in a great number of inſtances, the images pre⯑ſented by our paſt experience muſt remain in their firſt form, and preſerve their firſt proportions. Suppoſe, for inſtance, I have found by long obſervation, that of twenty ſhips, which go to ſea, only nineteen re⯑turn. Suppoſe I ſee at preſent twenty ſhips that leave the port: I transfer my paſt ex⯑perience to the future, and repreſent to my ſelf nineteen of theſe ſhips as returning in ſafety, and one as periſhing. Concerning this there can be no difficulty. But as we frequently run over thoſe ſeveral ideas of paſt events, in order to form a judgment concern⯑ing one ſingle event, which appears uncer⯑tain; this conſideration muſt change the firſt form of our ideas, and draw together the [238] divided images preſented by experience; ſince 'tis to it we refer the determination of that particular event, upon which we reaſon. Many of theſe images are ſuppos'd to con⯑cur, and a ſuperior number to concur on one ſide. Theſe agreeing images unite together, and render the idea more ſtrong and lively, not only than a mere fiction of the imagi⯑nation, but alſo than any idea, which is ſupported by a leſſer number of experiments. Each new experiment is as a new ſtroke of the pencil, which beſtows an additional vi⯑vacity on the colours, without either mul⯑tiplying or enlarging the figure. This ope⯑ration of the mind has been ſo fully ex⯑plain'd in treating of the probability of chance, that I need not here endeavour to render it more intelligible. Every paſt experiment may be conſider'd as a kind of chance; it being uncertain to us, whether the object will exiſt conformable to one experiment or another: And for this reaſon every thing that has been ſaid on the one ſubject is ap⯑plicable to both.

THUS upon the whole, contrary experi⯑ments produce an imperfect belief, either by weakening the habit, or by dividing and afterwards joining in different parts, that per⯑fect habit, which makes us conclude in ge⯑neral, [239] that inſtances, of which we have no experience, muſt neceſſarily reſemble thoſe of which we have.

TO juſtify ſtill farther this account of the ſecond ſpecies of probability, where we rea⯑ſon with knowledge and reflection from a contrariety of paſt experiments, I ſhall pro⯑poſe the following conſiderations, without fearing to give offence by that air of ſub⯑tilty, which attends them. Juſt reaſoning ought ſtill, perhaps, to retain its force, how⯑ever ſubtile; in the ſame manner as matter preſerves its ſolidity in the air, and fire, and animal ſpirits, as well as in the groſſer and more ſenſible forms.

FIRST, We may obſerve, that there is no probability ſo great as not to allow of a con⯑trary poſſibility; becauſe otherwiſe 'twou'd ceaſe to be a probability, and wou'd become a certainty. That probability of cauſes, which is moſt extenſive, and which we at preſent examine, depends on a contrariety of expe⯑riments; and 'tis evident an experiment in the paſt proves at leaſt a poſſibility for the future.

SECONDLY, The component parts of this poſſibility and probability are of the ſame nature, and differ in number only, but not in kind. It has been obſerv'd, that all ſingle [240] chances are entirely equal, and that the only circumſtance, which can give any event, that is contingent, a ſuperiority over another, is a ſuperior number of chances. In like man⯑ner, as the uncertainty of cauſes is diſcover'd by experience, which preſents us with a view of contrary events, 'tis plain, that as we transfer the paſt to the future, the known to the unknown, every paſt experiment has the ſame weight, and that 'tis only a ſupe⯑rior number of them, which can throw the ballance on any ſide. The poſſibility, therefore, which enters into every reaſon⯑ing of this kind, is compos'd of parts, which are of the ſame nature both among them⯑ſelves, and with thoſe, that compoſe the oppoſite probability.

THIRDLY, We may eſtabliſh it as a cer⯑tain maxim, that in all moral as well as na⯑tural phaenomena, wherever any cauſe con⯑ſiſts of a number of parts, and the effect encreaſes or diminiſhes, according to the va⯑riation of that number, the effect, properly ſpeaking, is a compounded one, and ariſes from the union of the ſeveral effects, that proceed from each part of the cauſe. Thus becauſe the gravity of a body encreaſes or diminiſhes by the encreaſe or diminution of its parts, we conclude that each part con⯑tains [241] this quality and contributes to the gra⯑vity of the whole. The abſence or preſence of a part of the cauſe is attended with that of a proportionable part of the effect. This connexion or conſtant conjunction ſuffici⯑ently proves the one part to be the cauſe of the other. As the belief, which we have of any event, encreaſes or diminiſhes according to the number of chances or paſt experiments, 'tis to be conſider'd as a com⯑pounded effect, of which each part ariſes from a proportionable number of chances or experiments.

LET us now join theſe three obſerva⯑tions, and ſee what concluſion we can draw from them. To every probability there is an oppoſite poſſibility. This poſſibility is compos'd of parts, that are entirely of the ſame nature with thoſe of the probabi⯑lity; and conſequently have the ſame in⯑fluence on the mind and underſtanding. The belief, which attends the probabili⯑ty, is a compounded effect, and is form'd by the concurrence of the ſeveral effects, which proceed from each part of the pro⯑bability. Since therefore each part of the probability contributes to the production of the belief, each part of the poſſibility muſt have the ſame influence on the oppoſite ſide; [242] the nature of theſe parts being entirely the ſame. The contrary belief, attending the poſſibility, implies a view of a certain ob⯑ject, as well as the probability does an op⯑poſite view. In this particular both theſe degrees of belief are alike. The only man⯑ner then, in which the ſuperior number of ſimilar component parts in the one can ex⯑ert its influence, and prevail above the in⯑ferior in the other, is by producing a ſtronger and more lively view of its object. Each part preſents a particular view; and all theſe views uniting together produce one general view, which is fuller and more diſtinct by the greater number of cauſes or principles, from which it is deriv'd.

THE component parts of the probability and poſſibility, being alike in their nature, muſt produce like effects; and the likeneſs of their effects conſiſts in this, that each of them preſents a view of a particular object, But tho' theſe parts be alike in their na⯑ture, they are very different in their quan⯑tity and number; and this difference muſt appear in the effect as well as the ſimilarity. Now as the view they preſent is in both caſes full and entire, and comprehends the object in all its parts, 'tis impoſſible that in this particular there can be any difference; [243] nor is there any thing but a ſuperior viva⯑city in the probability, ariſing from the con⯑currence of a ſuperior number of views, which can diſtinguiſh theſe effects.

HERE is almoſt the ſame argument in a different light. All our reaſonings concern⯑ing the probability of cauſes are founded on the transferring of paſt to future. The tranſ⯑ferring of any paſt experiment to the future is ſufficient to give us a view of the object; whether that experiment be ſingle, or com⯑bin'd with others of the ſame kind; whe⯑ther it be entire, or oppos'd by others of a contrary kind. Suppoſe, then, it acquires both theſe qualities of combination and op⯑poſition, it loſes not upon that account its former power of preſenting a view of the object, but only concurs with and oppoſes other experiments, that have a like influence. A queſtion, therefore, may ariſe concern⯑ing the manner both of the concurrence and oppoſition. As to the concurrence, there is only the choice left betwixt theſe two hypotheſes. Firſt, That the view of the object, occaſion'd by the transference of each paſt experiment, preſerves itſelf entire, and only multiplies the number of views. Or, ſecondly, That it runs into the other ſimilar and correſpondent views, and gives them a [244] ſuperior degree of force and vivacity. But that the firſt hypotheſis is erroneous, is evi⯑dent from experience, which informs us, that the belief, attending any reaſoning, conſiſts in one concluſion, not in a multitude of ſimilar ones, which wou'd only diſtract the mind, and in many caſes wou'd be too nu⯑merous to be comprehended diſtinctly by any finite capacity. It remains, therefore, as the only reaſonable opinion, that theſe ſimilar views run into each other, and unite their forces; ſo as to produce a ſtronger and clearer view, than what ariſes from any one alone. This is the manner, in which paſt experi⯑ments concur, when they are transfer'd to any future event. As to the manner of their oppoſition, 'tis evident, that as the contrary views are incompatible with each other, and 'tis impoſſible the object can at once exiſt conformable to both of them, their influence becomes mutually deſtructive, and the mind is determin'd tothe ſuperior only with that force, which remains after ſubſtracting the inferior.

I AM ſenſible how abſtruſe all this rea⯑ſoning muſt appear to the generality of rea⯑ders, who not being accuſtom'd to ſuch pro⯑found reflections on the intellectual facul⯑ties of the mind, will be apt to reject as chi⯑merical whatever ſtrikes not in with the [245] common receiv'd notions, and with the eaſieſt and moſt obvious principles of philo⯑ſophy. And no doubt there are ſome pains requir'd to enter into theſe arguments; tho' perhaps very little are neceſſary to perceive the imperfection of every vulgar hypotheſis on this ſubject, and the little light, which philoſophy can yet afford us in ſuch ſublime and ſuch curious ſpeculations. Let men be once fully perſwaded of theſe two principles, That there is nothing in any object, conſider'd in itſelf, which can afford us a reaſon for draw⯑ing a concluſion beyond it; and, That even after the obſervation of the frequent or con⯑ſtant conjunction of objects, we have no reaſon to draw any inference concerning any object beyond thoſe of which we have had experience; I ſay, let men be once fully convinc'd of theſe two principles, and this will throw them ſo looſe from all common ſyſtems, that they will make no difficulty of receiving any, which may appear the moſt extraordi⯑nary. Theſe principles we have found to be ſufficiently convincing, even with regard to our moſt certain reaſonings from cauſation: But I ſhall venture to affirm, that with re⯑gard to theſe conjectural or probable rea⯑ſonings they ſtill acquire a new degree of evidence.

[246] FIRST, 'Tis obvious, that in reaſonings of this kind, 'tis not the object preſented to us, which, conſider'd in itſelf, affords us any reaſon to draw a concluſion concerning any other object or event. For as this lat⯑ter object is ſuppos'd uncertain, and as the uncertainty is deriv'd from a conceal'd con⯑trariety of cauſes in the former, were any of the cauſes plac'd in the known qualities of that object, they wou'd no longer be con⯑ceal'd, nor wou'd our concluſion be uncer⯑tain.

BUT, ſecondly, 'tis equally obvious in this ſpecies of reaſoning, that if the transference of the paſt to the future were founded mere⯑ly on a concluſion of the underſtanding, it cou'd never occaſion any belief or aſſurance. When we transfer contrary experiments to the future, we can only repeat theſe con⯑trary experiments with their particular pro⯑portions; which cou'd not produce aſſu⯑rance in any ſingle event, upon which we reaſon, unleſs the fancy melted together all thoſe images that concur, and extracted from them one ſingle idea or image, which is intenſe and lively in proportion to the num⯑ber of experiments from which it is de⯑riv'd, and their ſuperiority above their an⯑tagoniſts. Our paſt experience preſents no [247] determinate object; and as our belief, how⯑ever faint, fixes itſelf on a determinate ob⯑ject, 'tis evident that the belief ariſes not merely from the transference of paſt to fu⯑ture, but from ſome operation of the fancy conjoin'd with it. This may lead us to conceive the manner, in which that faculty enters into all our reaſonings.

I SHALL conclude this ſubject with two reflections, which may deſerve our attention. The firſt may be explain'd after this man⯑ner. When the mind forms a reaſoning concerning any matter of fact, which is on⯑ly probable, it caſts its eye backward upon paſt experience, and transferring it to the future, is preſented with ſo many contrary views of its object, of which thoſe that are of the ſame kind uniting together, and run⯑ning into one act of the mind, ſerve to fortify and inliven it. But ſuppoſe that this multitude of views or glimpſes of an object proceeds not from experience, but from a voluntary act of the imagination; this ef⯑fect does not follow, or at leaſt, follows not in the ſame degree. For tho' cuſtom and education produce belief by ſuch a repeti⯑tion, as is not deriv'd from experience, yet this requires a long tract of time, along with a very frequent and undeſign'd repetition. [248] In general we may pronounce, that a per⯑ſon, who wou'd ^* voluntarily repeat any idea in his mind, tho' ſupported by one paſt experience, wou'd be no more inclin'd to believe the exiſtence of its object, than if he had contented himſelf with one ſur⯑vey of it. Beſide the effect of deſign; each act of the mind, being ſeparate and independent, has a ſeparate influence, and joins not its force with that of its fellows. Not being united by any common object, producing them, they have no relation to each other; and conſequently make no tran⯑ſition or union of forces. This phaenome⯑non we ſhall underſtand better afterwards.

MY ſecond reflection is founded on thoſe large probabilities, which the mind can judge of, and the minute differences it can obſerve betwixt them. When the chances or ex⯑periments on one ſide amount to ten thou⯑ſand, and on the other to ten thouſand and one, the judgment gives the preference to the latter, upon account of that ſuperiority; tho' 'tis plainly impoſſible for the mind to run over every particular view, and diſtinguiſh the ſuperior vivacity of the image ariſing from the ſuperior number, where the dif⯑ference is ſo inconſiderable. We have a [249] parallel inſtance in the affections. 'Tis e⯑vident, according to the principles above⯑mention'd, that when an object produces any paſſion in us, which varies according to the different quantity of the object; I ſay, 'tis evident, that the paſſion, proper⯑ly ſpeaking, is not a ſimple emotion, but a compounded one, of a great num⯑ber of weaker paſſions, deriv'd from a view of each part of the object. For otherwiſe 'twere impoſſible the paſſion ſhou'd encreaſe by the encreaſe of theſe parts. Thus a man, who deſires a thouſand pound, has in rea⯑lity a thouſand or more deſires, which u⯑niting together, ſeem to make only one paſſion; tho' the compoſition evidently be⯑trays itſelf upon every alteration of the ob⯑ject, by the preference he gives to the larg⯑er number, if ſuperior only by an unite. Yet nothing can be more certain, than that ſo ſmall a difference wou'd not be diſ⯑cernible in the paſſions, nor cou'd render them diſtinguiſhable from each other. The difference, therefore, of our conduct in prefer⯑ring the greater number depends not upon our paſſions, but upon cuſtom, and general rules. We have found in a multitude of inſtances, that the augmenting the numbers of any ſum augments the paſſion, where the num⯑bers [250] are preciſe and the difference ſenſible. The mind can perceive from its immediate feeling, that three guineas produce a greater paſſion than two; and this it transfers to larger numbers, becauſe of the reſemblance; and by a general rule aſſigns to a thouſand guineas, a ſtronger paſſion than to nine hun⯑dred and ninety nine. Theſe general rules we ſhall explain preſently.

BUT beſide theſe two ſpecies of probabi⯑ty, which are deriv'd from an imperfect ex⯑perience and from contrary cauſes, there is a third ariſing from ANALOGY, which dif⯑fers from them in ſome material circumſtan⯑ces. According to the hypotheſis above ex⯑plain'd all kinds of reaſoning from cauſes or effects are founded on two particulars, viz. the conſtant conjunction of any two objects in all paſt experience, and the reſemblance of a preſent object to any one of them. The effect of theſe two particulars is, that the preſent object invigorates and inlivens the imagination; and the reſemblance, along with the conſtant union, conveys this force and vivacity to the related idea; which we are therefore ſaid to believe, or aſſent to. If you weaken either the union or reſem⯑blance, you weaken the principle of tranſi⯑tion, and of conſequence that belief, which [251] ariſes from it. The vivacity of the firſt im⯑preſſion cannot be fully convey'd to the re⯑lated idea, either where the conjunction of their objects is not conſtant, or where the preſent impreſſion does not perfectly reſem⯑ble any of thoſe, whoſe union we are ac⯑cuſtom'd to obſerve. In thoſe probabilities of chance and cauſes above-explain'd, 'tis the conſtancy of the union, which is dimi⯑niſh'd; and in the probability deriv'd from analogy, 'tis the reſemblance only, which is affected. Without ſome degree of reſem⯑blance, as well as union, 'tis impoſſible there can be any reaſoning: but as this re⯑ſemblance admits of many different degrees, the reaſoning becomes proportionably more or leſs firm and certain. An experiment loſes of its force, when transferr'd to in⯑ſtances, which are not exactly reſembling; tho' 'tis evident it may ſtill retain as much as may be the foundation of probability, as long as there is any reſemblance remaining.

SECT. XIII. Of unphiloſophical probability.

ALL theſe kinds of probability are receiv'd by philoſophers, and al⯑low'd to be reaſonable foundations of belief and opinion. But there are others, that are deriv'd from the ſame principles, tho' they have not had the good fortune to obtain the ſame ſanction. The firſt probability of this kind may be accounted for thus. The di⯑minution of the union, and of the reſem⯑blance, as above explained, diminiſhes the facility of the tranſition, and by that means weakens the evidence; and we may farther obſerve, that the ſame diminution of the evidence will follow from a diminution of the impreſſion, and from the ſhading of thoſe colours, under which it appears to the memory or ſenſes. The argument, which we found on any matter of fact we remem⯑ber, is more or leſs convincing, according as the fact is recent or remote; and tho' the difference in theſe degrees of evidence be not receiv'd by philoſophy as ſolid and legitimate; becauſe in that caſe an argument [253] muſt have a different force to day, from what it ſhall have a month hence; yet not⯑withſtanding the oppoſition of philoſophy, 'tis certain, this circumſtance has a conſi⯑derable influence on the underſtanding, and ſecretly changes the authority of the ſame argument, according to the different times, in which it is propos'd to us. A greater force and vivacity in the impreſſion natural⯑ly conveys a greater to the related idea; and 'tis on the degrees of force and vivaci⯑ty, that the belief depends, according to the foregoing ſyſtem.

THERE is a ſecond difference, which we may frequently obſerve in our degrees of belief and aſſurance, and which never fails to take place, tho' diſclaim'd by philoſophers. An experiment, that is recent and freſh in the memory, affects us more than one that is in ſome meaſure obliterated; and has a ſuperior influence on the judgment, as well as on the paſſions. A lively impreſſion pro⯑duces more aſſurance than a faint one; be⯑cauſe it has more original force to commu⯑nicate to the related idea, which thereby acquires a greater force and vivacity. A recent obſervation has a like effect; be⯑cauſe the cuſtom and tranſition is there more entire, and preſerves better the origi⯑nal [254] force in the communication. Thus a drunkard, who has ſeen his companion die of a debauch, is ſtruck with that inſtance for ſome time, and dreads a like accident for himſelf: But as the memory of it de⯑cays away by degrees, his former ſecurity returns, and the danger ſeems leſs certain and real.

I ADD, as a third inſtance of this kind, that tho' our reaſonings from proofs and from probabilities be conſiderably different from each other, yet the former ſpecies of reaſoning often degenerates inſenſibly into the latter, by nothing but the multitude of connected ar⯑guments. 'Tis certain, that when an infe⯑rence is drawn immediately from an object, without any intermediate cauſe or effect, the conviction is much ſtronger, and the per⯑ſuaſion more lively, than when the imagi⯑nation is carry'd thro' a long chain of con⯑nected arguments, however infallible the connexion of each link may be eſteem'd. 'Tis from the original impreſſion, that the vivacity of all the ideas is deriv'd, by means of the cuſtomary tranſition of the imagina⯑tion; and 'tis evident this vivacity muſt gra⯑dually decay in proportion to the diſtance, and muſt loſe ſomewhat in each tranſition. Sometimes this diſtance has a greater influ⯑ence [255] than even contrary experiments wou'd have; and a man may receive a more lively conviction from a probable reaſoning, which is cloſe and immediate, than from a long chain of conſequences, tho' juſt and con⯑cluſive in each part. Nay 'tis ſeldom ſuch reaſonings produce any conviction; and one muſt have a very ſtrong and firm ima⯑gination to preſerve the evidence to the end, where it paſſes thro' ſo many ſtages.

BUT here it may not be amiſs to re⯑mark a very curious phaenomenon, which the preſent ſubject ſuggeſts to us. 'Tis e⯑vident there is no point of ancient hiſtory, of which we can have any aſſurance, but by paſſing thro' many millions of cauſes and effects, and thro' a chain of arguments of almoſt an immeaſurable length. Before the knowledge of the fact cou'd come to the firſt hiſtorian, it muſt be convey'd thro' many mouths; and after it is committed to writing, each new copy is a new object, of which the connexion with the foregoing is known only by experience and obſervation. Perhaps, therefore, it may be concluded from the precedent reaſoning, that the evidence of all ancient hiſtory muſt now be loſt; or at leaſt, will be loſt in time, as the chain of cauſes encreaſes, and runs on to a greater length. [256] But as it ſeems contrary to common ſenſe to think, that if the republic of letters, and the art of printing continue on the ſame footing as at preſent, our poſterity, even af⯑ter a thouſand ages, can ever doubt if there has been ſuch a man as JULIUS CAESAR; this may be conſider'd as an objection to the preſent ſyſtem. If belief conſiſted only in a certain vivacity, convey'd from an ori⯑ginal impreſſion, it wou'd decay by the length of the tranſition, and muſt at laſt be utterly extinguiſh'd: And vice verſa, if belief on ſome occaſions be not capable of ſuch an extinction; it muſt be ſomething different from that vivacity.

BEFORE I anſwer this objection I ſhall obſerve, that from this topic there has been borrow'd a very celebrated argument againſt the Chriſtian Religion; but with this differ⯑ence, that the connexion betwixt each link of the chain in human evidence has been there ſuppos'd not to go beyond probability, and to be liable to a degree of doubt and un⯑certainty. And indeed it muſt be confeſt, that in this manner of conſidering the ſub⯑ject, (which however is not a true one) there is no hiſtory or tradition, but what muſt in the end loſe all its force and evidence. Eve⯑ry new probability diminiſhes the original [257] conviction; and however great that convic⯑tion may be ſuppos'd, 'tis impoſſible it can ſubſiſt under ſuch re-iterated diminutions. This is true in general; tho' we ſhall find ^* afterwards, that there is one very me⯑morable exception, which is of vaſt conſe⯑quence in the preſent ſubject of the under⯑ſtanding.

MEAN while to give a ſolution of the preceding objection upon the ſuppoſition, that hiſtorical evidence amounts at firſt to an entire proof; let us conſider, that tho' the links are innumerable, that connect any original fact with the preſent impreſ⯑ſion, which is the foundation of belief; yet they are all of the ſame kind, and depend on the fidelity of Printers and Copiſts. One edition paſſes into another, and that into a third, and ſo on, till we come to that vo⯑lume we peruſe at preſent. There is no va⯑riation in the ſteps. After we know one, we know all of them; and after we have made one, we can have no ſcruple as to the reſt. This circumſtance alone preſerves the evi⯑dence of hiſtory, and will perpetuate the memory of the preſent age to the lateſt po⯑ſterity. If all the long chain of cauſes and effects, which connect any paſt event with [258] any volume of hiſtory, were compos'd of parts different from each other, and which 'twere neceſſary for the mind diſtinctly to conceive, 'tis impoſſible we ſhou'd preſerve to the end any belief or evidence. But as moſt of theſe proofs are perfectly reſembling, the mind runs eaſily along them, jumps from one part to another with facility, and forms but a confus'd and general notion of each link. By this means a long chain of argu⯑ment, has as little effect in diminiſhing the original vivacity, as a much ſhorter wou'd have, if compos'd of parts, which were dif⯑ferent from each other, and of which each requir'd a diſtinct conſideration.

A FOURTH unphiloſophical ſpecies of probability is that deriv'd from general rules, which we raſhly form to ourſelves, and which are the ſource of what we properly call PREJUDICE. An Iriſhman cannot have wit, and a Frenchman cannot have ſo⯑lidity; for which reaſon, tho' the converſa⯑tion of the former in any inſtance be viſibly very agreeable, and of the latter very judi⯑cious, we have entertain'd ſuch a prejudice a⯑gainſt them, that they muſt be dunces or fops in ſpite of ſenſe and reaſon. Human nature is very ſubject to errors of this kind; and perhaps this nation as much as any o⯑ther.

[259] SHOU'D it be demanded why men form general rules, and allow them to in⯑fluence their judgment, even contrary to preſent obſervation and experience, I ſhou'd reply, that in my opinion it proceeds from thoſe very principles, on which all judgments concerning cauſes and effects de⯑pend. Our judgments concerning cauſe and effect are deriv'd from habit and experience; and when we have been accuſtom'd to ſee one object united to another, our imagina⯑tion paſſes from the firſt to the ſecond, by a natural tranſition, which precedes reflection, and which cannot be prevented by it. Now 'tis the nature of cuſtom not only to operate with its full force, when objects are pre⯑ſented, that are exactly the ſame with thoſe to which we have been accuſtom'd; but alſo to operate in an inferior degree, when we diſ⯑cover ſuch as are ſimilar; and tho' the ha⯑bit loſes ſomewhat of its force by every dif⯑ference, yet 'tis ſeldom entirely deſtroy'd, where any conſiderable circumſtances re⯑main the ſame. A man, who has contract⯑ed a cuſtom of eating fruit by the uſe of pears or peaches, will ſatisfy himſelf with melons, where he cannot find his favourite fruit; as one, who has become a drunkard by the uſe of red wines, will be carried al⯑moſt [260] with the ſame violence to white, if preſented to him. From this principle I have accounted for that ſpecies of probabi⯑lity, deriv'd from analogy, where we tranſ⯑fer our experience in paſt inſtances to ob⯑jects which are reſembling, but are not ex⯑actly the ſame with thoſe concerning which we have had experience. In proportion as the reſemblance decays, the probability di⯑miniſhes; but ſtill has ſome force as long as there remain any traces of the reſemblance.

THIS obſervation we may carry farther; and may remark, that tho' cuſtom be the foundation of all our judgments, yet ſome⯑times it has an effect on the imagination in oppoſition to the judgment, and produces a contrariety in our ſentiments concerning the ſame object. I explain myſelf. In almoſt all kinds of cauſes there is a complication of circumſtances, of which ſome are eſſen⯑tial, and others ſuperfluous; ſome are abſo⯑lutely requiſite to the production of the ef⯑fect, and others are only conjoin'd by acci⯑dent. Now we may obſerve, that when theſe ſuperfluous circumſtances are nume⯑rous, and remarkable, and frequently con⯑join'd with the eſſential, they have ſuch an influence on the imagination, that even in the abſence of the latter they carry us on [261] to the conception of the uſual effect, and give to that conception a force and vivacity, which make it ſuperior to the mere fic⯑tions of the fancy. We may correct this propenſity by a reflection on the nature of thoſe circumſtances; but 'tis ſtill certain, that cuſtom takes the ſtart, and gives a biaſs to the imagination.

TO illuſtrate this by a familiar inſtance, let us conſider the caſe of a man, who be⯑ing hung out from a high tower in a cage of iron cannot forbear trembling, when he ſur⯑veys the precipice below him, tho' he knows himſelf to be perfectly ſecure from falling, by his experience of the ſolidity of the iron, which ſupports him; and tho' the ideas of fall and deſcent, and harm and death, be deriv'd ſolely from cuſtom and experience. The ſame cuſtom goes beyond the inſtances, from which it is deriv'd, and to which it perfectly correſponds; and influences his ideas of ſuch objects as are in ſome reſpect reſembling, but fall not preciſely under the ſame rule. The circumſtances of depth and deſcent ſtrike ſo ſtrongly upon him, that their influence cannot be deſtroy'd by the contrary circumſtances of ſupport and ſoli⯑dity, which ought to give him a perfect ſe⯑curity. His imagination runs away with [262] its object, and excites a paſſion proportion'd to it. That paſſion returns back upon the imagination and inlivens the idea; which lively idea has a new influence on the paſ⯑ſion, and in its turn augments its force and violence; and both his fancy and affections, thus mutually ſupporting each other, cauſe the whole to have a very great influence upon him.

BUT why need we ſeek for other in⯑ſtances, while the preſent ſubject of philo⯑ſophical probabilities offers us ſo obvious an one, in the oppoſition betwixt the judgment and imagination ariſing from theſe effects of cuſtom? According to my ſyſtem, all rea⯑ſonings are nothing but the effects of cuſ⯑tom; and cuſtom has no influence, but by inlivening the imagination, and giving us a ſtrong conception of any object. It may, therefore, be concluded, that our judgment and imagination can never be contrary, and that cuſtom cannot operate on the latter faculty after ſuch a manner, as to render it oppoſite to the former. This difficulty we can remove after no other manner, than by ſuppoſing the influence of general rules. We ſhall afterwards ^* take notice of ſome ge⯑neral rules, by which we ought to regulate [263] our judgment concerning cauſes and effects; and theſe rules are form'd on the nature of our underſtanding, and on our experience of its operations in the judgments we form concerning objects. By them we learn to diſtinguiſh the accidental circumſtances from the efficacious cauſes; and when we find that an effect can be produc'd without the concurrence of any particular circumſtance, we conclude that that circumſtance makes not a part of the efficacious cauſe, however frequently conjoin'd with it. But as this frequent conjunction neceſſarily makes it have ſome effect on the imagination, in ſpite of the oppoſite concluſion from general rules, the oppoſition of theſe two principles produces a contrariety in our thoughts, and cauſes us to aſcribe the one inference to our judgment, and the other to our imagina⯑tion. The general rule is attributed to our judgment; as being more extenſive and con⯑ſtant. The exception to the imagination; as being more capricious and uncertain.

THUS our general rules are in a manner ſet in oppoſition to each other. When an object appears, that reſembles any cauſe in very conſiderable circumſtances, the imagi⯑nation naturally carries us to a lively con⯑ception of the uſual effect, tho' the object [264] be different in the moſt material and moſt efficacious circumſtances from that cauſe. Here is the firſt influence of general rules. But when we take a review of this act of the mind, and compare it with the more ge⯑neral and authentic operations of the under⯑ſtanding, we find it to be of an irregular na⯑ture, and deſtructive of all the moſt eſtabliſh'd principles of reaſonings; which is the cauſe of our rejecting it. This is a ſecond influ⯑ence of general rules, and implies the con⯑demnation of the former. Sometimes the one, ſometimes the other prevails, accord⯑ing to the diſpoſition and character of the perſon. The vulgar are commonly guided by the firſt, and wiſe men by the ſecond. Mean while the ſceptics may here have the pleaſure of obſerving a new and ſignal con⯑tradiction in our reaſon, and of ſeeing all philoſophy ready to be ſubverted by a prin⯑ciple of human nature, and again ſav'd by a new direction of the very ſame principle. The following of general rules is a very un⯑philoſophical ſpecies of probability; and yet 'tis only by following them that we can cor⯑rect this, and all other unphiloſophical pro⯑babilities.

SINCE we have inſtances, where gene⯑ral rules operate on the imagination even [265] contrary to the judgment, we need not be ſurpriz'd to ſee their effects encreaſe, when conjoin'd with that latter faculty, and to obſerve that they beſtow on the ideas they preſent to us a force ſuperior to what at⯑tends any other. Every one knows, there is an indirect manner of inſinuating praiſe or blame, which is much leſs ſhocking than the open flattery or cenſure of any perſon. However he may communicate his ſenti⯑ments by ſuch ſecret inſinuations, and make them known with equal certainty as by the open diſcovery of them, 'tis certain that their influence is not equally ſtrong and powerful. One who laſhes me with con⯑ceal'd ſtrokes of ſatire, moves not my indig⯑nation to ſuch a degree, as if he flatly told me I was a fool and coxcomb; tho' I e⯑qually underſtand his meaning, as if he did. This difference is to be attributed to the in⯑fluence of general rules.

WHETHER a perſon openly abuſes me, or ſlyly intimates his contempt, in neither caſe do I immediately perceive his ſentiment or opinion; and 'tis only by ſigns, that is, by its effects, I become ſenſible of it. The only difference, then, betwixt theſe two caſes conſiſts in this, that in the open diſco⯑very of his ſentiments he makes uſe of ſigns, [266] which are general and univerſal; and in the ſecret intimation employs ſuch as are more ſingular and uncommon. The effect of this circumſtance is, that the imagination, in running from the preſent impreſſion to the abſent idea, makes the tranſition with greater facility, and conſequently conceives the ob⯑ject with greater force, where the connexion is common and univerſal, than where it is more rare and particular. Accordingly we may obſerve, that the open declaration of our ſentiments is call'd the taking off the maſk, as the ſecret intimation of our opi⯑nions is ſaid to be the veiling of them. The difference betwixt an idea produc'd by a general connexion, and that ariſing from a particular one is here compar'd to the dif⯑ference betwixt an impreſſion and an idea. This difference in the imagination has a ſuitable effect on the paſſions; and this ef⯑fect is augmented by another circumſtance. A ſecret intimation of anger or contempt ſhews that we ſtill have ſome conſideration for the perſon, and avoid the directly a⯑buſing him. This makes a conceal'd ſatire leſs diſagreeable; but ſtill this depends on the ſame principle. For if an idea were not more feeble, when only intimated, it wou'd never be eſteem'd a mark of greater [267] reſpect to proceed in this method than in the other.

SOMETIMES ſcurrility is leſs diſpleaſing than delicate ſatire, becauſe it revenges us in a manner for the injury at the very time it is committed, by affording us a juſt rea⯑ſon to blame and contemn the perſon, who injures us. But this phaenomenon likewiſe depends upon the ſame principle. For why do we blame all groſs and injurious language, unleſs it be, becauſe we eſteem it contrary to good breeding and humanity? And why is it contrary, unleſs it be more ſhocking than any delicate ſatire? The rules of good⯑breeding condemn whatever is openly diſ⯑obliging, and gives a ſenſible pain and con⯑fuſion to thoſe, with whom we converſe. After this is once eſtabliſh'd, abuſive lan⯑guage is univerſally blam'd, and gives leſs pain upon account of its coarſeneſs and in⯑civility, which render the perſon deſpicable, that employs it. It becomes leſs diſagree⯑able, merely becauſe originally it is more ſo; and 'tis more diſagreeable, becauſe it affords an inference by general and common rules, that are palpable and undeniable.

TO this explication of the different in⯑fluence of open and conceal'd flattery or ſatire, I ſhall add the conſideration of ano⯑ther [268] phaenomenon, which is analogous to it. There are many particulars in the point of honour both of men and women, whoſe violations, when open and avow'd, the world never excuſes, but which it is more apt to overlook, when the appearances are ſav'd, and the tranſgreſſion is ſecret and conceal'd. Even thoſe, who know with equal certainty, that the fault is committed, pardon it more eaſily, when the proofs ſeem in ſome mea⯑ſure oblique and equivocal, than when they are direct and undeniable. The ſame idea is preſented in both caſes, and, properly ſpeaking, is equally aſſented to by the judg⯑ment; and yet its influence is different, be⯑cauſe of the different manner, in which it is preſented.

Now if we compare theſe two caſes, of the open and conceal'd violations of the laws of honour, we ſhall find, that the difference betwixt them conſiſts in this, that in the firſt caſe the ſign, from which we infer the blameable action, is ſingle, and ſuffices a⯑lone to be the foundation of our reaſoning and judgment; whereas in the latter the ſigns are numerous, and decide little or no⯑thing when alone and unaccompany'd with many minute circumſtances, which are al⯑moſt imperceptible. But 'tis certainly true, [269] that any reaſoning is always the more con⯑vincing, the more ſingle and united it is to the eye, and the leſs exerciſe it gives to the imagination to collect all its parts, and run from them to the correlative idea, which forms the concluſion. The labour of the thought diſturbs the regular progreſs of the ſentiments, as we ſhall obſerve preſently ^*. The idea ſtrikes not on us with ſuch viva⯑city; and conſequently has no ſuch influ⯑ence on the paſſion and imagination.

FROM the ſame principles we may ac⯑count for thoſe obſervations of the CAR⯑DINAL DE RETZ, that there are many things, in which the world wiſhes to be de⯑ceiv'd; and that it more eaſily excuſes a per⯑ſon in acting than in talking contrary to the decorum of his profeſſion and character. A fault in words is commonly more open and diſtinct than one in actions, which admit of many palliating excuſes, and decide not ſo clearly concerning the intention and views of the actor.

THUS it appears upon the whole, that every kind of opinion or judgment, which amounts not to knowledge, is deriv'd en⯑tirely from the force and vivacity of the perception, and that theſe qualities conſti⯑tute [270] in the mind, what we call the BELIEF of the exiſtence of any object. This force and this vivacity are moſt conſpicuous in the memory; and therefore our confidence in the veracity of that faculty is the greateſt imaginable, and equals in many reſpects the aſſurance of a demonſtration. The next de⯑gree of theſe qualities is that deriv'd from the relation of cauſe and effect; and this too is very great, eſpecially when the conjunc⯑tion is found by experience to be perfectly conſtant, and when the object, which is preſent to us, exactly reſembles thoſe, of which we have had experience. But below this degree of evidence there are many o⯑thers, which have an influence on the paſ⯑ſions and imagination, proportion'd to that degree of force and vivacity, which they communicate to the ideas. 'Tis by habit we make the tranſition from cauſe to effect; and 'tis from ſome preſent impreſſion we borrow that vivacity, which we diffuſe over the correlative idea. But when we have not obſerv'd a ſufficient number of inſtances, to produce a ſtrong habit; or when theſe in⯑ſtances are contrary to each other; or when the reſemblance is not exact; or the preſent impreſſion is faint and obſcure; or the ex⯑perience in ſome meaſure obliterated from [271] the memory; or the connexion dependent on a long chain of objects; or the inference deriv'd from general rules, and yet not con⯑formable to them: In all theſe caſes the evi⯑dence diminiſhes by the diminution of the force and intenſeneſs of the idea. This therefore is the nature of the judgment and probability.

WHAT principally gives authority to this ſyſtem is, beſide the undoubted arguments, upon which each part is founded, the agree⯑ment of theſe parts, and the neceſſity of one to explain another. The belief, which attends our memory, is of the ſame nature with that, which is deriv'd from our judg⯑ments: Nor is there any difference betwixt that judgment, which is deriv'd from a con⯑ſtant and uniform connexion of cauſes and effects, and that which depends upon an in⯑terrupted and uncertain. 'Tis indeed evi⯑dent, that in all determinations, where the mind decides from contrary experiments, 'tis firſt divided within itſelf, and has an inclination to either ſide in proportion to the number of experiments we have ſeen and remember. This conteſt is at laſt determin'd to the advantage of that ſide, where we ob⯑ſerve a ſuperior number of theſe experi⯑ments; but ſtill with a diminution of force [272] in the evidence correſpondent to the number of the oppoſite experiments. Each poſſibi⯑lity, of which the probability is compos'd, operates ſeparately upon the imagination; and 'tis the larger collection of poſſibilities, which at laſt prevails, and that with a force propor⯑tionable to its ſuperiority. All theſe phaeno⯑mena lead directly to the precedent ſyſtem; nor will it ever be poſſible upon any other principles to give a ſatisfactory and conſiſtent explication of them. Without conſidering theſe judgments as the effects of cuſtom on the imagination, we ſhall loſe ourſelves in perpetual contradiction and abſurdity.

SECT. XIV. Of the idea of neceſſary connexion.

HAVING thus explain'd the manner, in which we reaſon beyond our imme⯑diate impreſſions, and conclude that ſuch par⯑ticular cauſes muſt have ſuch particular ef⯑fects; we muſt now return upon our foot⯑ſteps to examine that queſtion, which ^* firſt occur'd to us, and which we dropt in our way, viz. What is our idea of neceſſity, when we ſay that two objects are neceſſarily [273] connected together. Upon this head I repeat what I have often had occaſion to obſerve, that as we have no idea, that is not deriv'd from an impreſſion, we muſt find ſome im⯑preſſion, that gives riſe to this idea of ne⯑ceſſity, if we aſſert we have really ſuch an idea. In order to this I conſider, in what objects neceſſity is commonly ſuppos'd to lie; and finding that it is always aſcrib'd to cauſes and effects, I turn my eye to two objects ſuppos'd to be plac'd in that relation; and examine them in all the ſituations, of which they are ſuſceptible. I immediately perceive, that they are contiguous in time and place, and that the object we call cauſe precedes the other we call effect. In no one inſtance can I go any farther, nor is it poſſible for me to diſcover any third relation betwixt theſe objects. I therefore enlarge my view to comprehend ſeveral inſtance; where I find like objects always exiſting in like relations of contiguity and ſucceſſion. At firſt ſight this ſeems to ſerve but little to my purpoſe. The reflection on ſeveral inſtances only repeats the ſame objects; and there⯑fore can never give riſe to a new idea. But upon farther enquiry I find, that the repe⯑tition is not in every particular the ſame, but produces a new impreſſion, and by that [274] means the idea, which I at preſent examine. For after a frequent repetition, I find, that upon the appearance of one of the objects, the mind is determin'd by cuſtom to con⯑ſider its uſual attendant, and to conſider it in a ſtronger light upon account of its re⯑lation to the firſt object. 'Tis this impreſ⯑ſion, then, or determination, which affords me the idea of neceſſity.

I DOUBT not but theſe conſequences will at firſt ſight be receiv'd without diffi⯑culty, as being evident deductions from prin⯑ciples, which we have already eſtabliſh'd, and which we have often employ'd in our reaſonings. This evidence both in the firſt principles, and in the deductions, may ſe⯑duce us unwarily into the concluſion, and make us imagine it contains nothing extra⯑ordinary, nor worthy of our curioſity. But tho' ſuch an inadvertence may facilitate the reception of this reaſoning, 'twill make it be the more eaſily forgot; for which reaſon I think it proper to give warning, that I have juſt now examin'd one of the moſt ſublime queſtions in philoſophy, viz. that concerning the power and efficacy of cauſes; where all the ſciences ſeem ſo much inte⯑reſted. Such a warning will naturally rouze up the attention of the reader, and make [275] him deſire a more full account of my doc⯑trine, as well as of the arguments, on which it is founded. This requeſt is ſo reaſonable, that I cannot refuſe complying with it; eſ⯑pecially as I am hopeful that theſe princi⯑ples, the more they are examin'd, will ac⯑quire the more force and evidence.

THERE is no queſtion, which on account of its importance, as well as difficulty, has caus'd more diſputes both among antient and modern philoſophers, than this concerning the efficacy of cauſes, or that quality which makes them be follow'd by their effects. But before they enter'd upon theſe diſputes, methinks it wou'd not have been improper to have examin'd what idea we have of that efficacy, which is the ſubject of the con⯑troverſy. This is what I find principally wanting in their reaſonings, and what I ſhall here endeavour to ſupply.

I BEGIN with obſerving that the terms of efficacy, agency, power, force, energy, ne⯑ceſſity, connexion, and productive quality, are all nearly ſynonimous; and therefore 'tis an abſurdity to employ any of them in de⯑fining the reſt. By this obſervation we re⯑ject at once all the vulgar definitions, which philoſophers have given of power and effi⯑cacy; and inſtead of ſearching for the idea [276] in theſe definitions, muſt look for it in the impreſſions, from which it is originally de⯑riv'd. If it be a compound idea, it muſt ariſe from compound impreſſions. If ſimple, from ſimple impreſſions.

I BELIEVE the moſt general and moſt popular explication of this matter, is to ſay, ^* that finding from experience, that there are ſeveral new productions in matter, ſuch as the motions and variations of body, and concluding that there muſt ſomewhere be a power capable of producing them, we arrive at laſt by this reaſoning at the idea of power and efficacy. But to be convinc'd that this explication is more popular than philoſophical, we need but reflect on two very obvious principles. Firſt, That reaſon alone can never give riſe to any original idea, and ſecondly, that reaſon, as diſtin⯑guiſh'd from experience, can never make us conclude, that a cauſe or productive qua⯑lity is abſolutely requiſite to every beginning of exiſtence. Both theſe conſiderations have been ſufficiently explain'd; and therefore ſhall not at preſent be any farther inſiſted on.

I SHALL only infer from them, that ſince reaſon can never give riſe to the idea of efficacy, that idea muſt be deriv'd from expe⯑rience, and from ſome particular inſtances of [277] this efficacy, which make their paſſage into the mind by the common channels of ſen⯑ſation or reflection. Ideas always repreſent their objects or impreſſions; and vice verſa, there are ſome objects neceſſary to give riſe to every idea. If we pretend, therefore, to have any juſt idea of this efficacy, we muſt produce ſome inſtance, wherein the efficacy is plainly diſcoverable to the mind, and its operations obvious to our conſciouſneſs or ſenſation. By the refuſal of this, we ac⯑knowledge, that the idea is impoſſible and imaginary; ſince the principle of innate ideas, which alone can ſave us from this dilemma, has been already refuted, and is now al⯑moſt univerſally rejected in the learned world. Our preſent buſineſs, then, muſt be to find ſome natural production, where the operation and efficacy of a cauſe can be clear⯑ly conceiv'd and comprehended by the mind, without any danger of obſcurity or miſtake.

IN this reſearch we meet with very little encouragement from that prodigious diver⯑ſity, which is found in the opinions of thoſe philoſophers, who have pretended to explain the ſecret force and energy of cauſes ^*. There are ſome, who maintain, that bodies operate [278] by their ſubſtantial form; others, by their accidents or qualities; ſeveral, by their matter and form; ſome, by their form and accidents; others, by certain virtues and fa⯑culties diſtinct from all this. All theſe ſen⯑timents again are mix'd and vary'd in a thouſand different ways; and form a ſtrong preſumption, that none of them have any ſolidity or evidence, and that the ſuppoſi⯑tion of an efficacy in any of the known qualities of matter is entirely without foun⯑dation. This preſumption muſt encreaſe upon us, when we conſider, that theſe prin⯑ciples of ſubſtantial forms, and accidents, and faculties, are not in reality any of the known properties of bodies, but are perfectly unintelligible and inexplicable. For 'tis evi⯑dent philoſophers wou'd never have had recourſe to ſuch obſcure and uncertian principles had they met with any ſa⯑tisfaction in ſuch as are clear and intelli⯑gible; eſpecially in ſuch an affair as this, which muſt be an object of the ſimpleſt un⯑derſtanding, if not of the ſenſes. Upon the whole, we may conclude, that 'tis impoſ⯑ſible in any one inſtance to ſhew the prin⯑ciple, in which the force and agency of a cauſe is plac'd; and that the moſt refin'd and moſt vulgar underſtandings are equally [279] at a loſs in this particular. If any one think proper to refute this aſſertion, he need not put himſelf to the trouble of inventing any long reaſonings; but may at once ſhew us an inſtance of a cauſe, where we diſ⯑cover the power or operating principle. This defiance we are oblig'd frequently to make uſe of, as being almoſt the only means of proving a negative in philoſophy.

THE ſmall ſucceſs, which has been met with in all the attempts to fix this power, has at laſt oblig'd philoſophers to conclude, that the ultimate force and efficacy of na⯑ture is perfectly unknown to us, and that 'tis in vain we ſearch for it in all the known qualities of matter. In this opinion they are almoſt unanimous; and 'tis only in the inference they draw from it, that they diſ⯑cover any difference in their ſentiments. For ſome of them, as the Carteſians in particular, having eſtabliſh'd it as a principle, that we are perfectly acquainted with the eſſence of mat⯑ter, have very naturally inferr'd, that it is en⯑dow'd with no efficacy, and that 'tis impoſ⯑ſible for it of itſelf to communicate motion, or produce any of thoſe effects, which we aſcribe to it. As the eſſence of matter con⯑ſiſts in extenſion, and as extenſion implies not actual motion, but only mobility; they [280] conclude, that the energy, which produces the motion, cannot lie in the extenſion.

THIS concluſion leads them into another, which they regard as perfectly unavoidable. Matter, ſay they, is in itſelf entirely unac⯑tive, and depriv'd of any power, by which it may produce, or continue, or communicate motion: But ſince theſe effects are evident to our ſenſes, and ſince the power, that pro⯑duces them, muſt be plac'd ſomewhere, it muſt lie in the DEITY, or that divine be⯑ing, who contains in his nature all excel⯑lency and perfection. 'Tis the deity, there⯑fore, who is the prime mover of the uni⯑verſe, and who not only firſt created mat⯑ter, and gave it's original impulſe, but like⯑wiſe by a continu'd exertion of omnipo⯑tence, ſupports its exiſtence, and ſucceſſively beſtows on it all thoſe motions, and confi⯑gurations, and qualities, with which it is endow'd.

THIS opinion is certainly very curious, and well worth our attention; but 'twill appear ſuperfluous to examine it in this place, if we reflect a moment on our pre⯑ſent purpoſe in taking notice of it. We have eſtabliſh'd it as a principle, that as all ideas are deriv'd from impreſſions, or ſome precedent perceptions, 'tis impoſſible we can [281] have any idea of power and efficacy, unleſs ſome inſtances can be produc'd, wherein this power is perceiv'd to exert itſelf. Now as theſe inſtances can never be diſcover'd in body, the Carteſians, proceeding upon their principle of innate ideas, have had recourſe to a ſupreme ſpirit or deity, whom they con⯑ſider as the only active being in the univerſe, and as the immediate cauſe of every altera⯑tion in matter. But the principle of innate ideas being allow'd to be falſe, it follows, that the ſuppoſition of a deity can ſerve us in no ſtead, in accounting for that idea of agency, which we ſearch for in vain in all the objects, which are preſented to our ſenſes, or which we are internally conſcious of in our own minds. For if every idea be deriv'd from an impreſſion, the idea of a deity pro⯑ceeds from the ſame origin; and if no im⯑preſſion, either of ſenſation or reflection, im⯑plies any force or efficacy, 'tis equally im⯑poſſible to diſcover or even imagine any ſuch active principle in the deity. Since theſe philoſophers, therefore, have concluded, that matter cannot be endow'd with any effica⯑cious principle, becauſe 'tis impoſſible to diſcover in it ſuch a principle; the ſame courſe of reaſoning ſhou'd determine them to exclude it from the ſupreme being. Or if [282] they eſtem that opinion abſurd and impious, as it really is, I ſhall tell them how they may avoid it; and that is, by concluding from the very firſt, that they have no ade⯑quate idea of power or efficacy in any ob⯑ject; ſince neither in body nor ſpirit, nei⯑ther in ſuperior nor inferior natures, are they able to diſcover one ſingle inſtance of it.

THE ſame concluſion is unavoidable up⯑on the hypotheſis of thoſe, who maintain the efficacy of ſecond cauſes, and attribute a de⯑rivative, but a real power and energy to matter. For as they confeſs, that this ener⯑gy lies not in any of the known qualities of matter, the difficulty ſtill remains concern⯑ing the origin of its idea. If we have real⯑ly an idea of power, we may attribute power to an unknown quality: But as 'tis impoſ⯑ſible, that that idea can be deriv'd from ſuch a quality, and as there is nothing in known qualities, which can produce it; it follows that we deceive ourſelves, when we imagine we are poſſeſt of any idea of this kind, after the manner we commonly underſtand it. All ideas are deriv'd from, and repreſent impreſ⯑ſions. We never have any impreſſion, that contains any power or efficacy. We never therefore have any idea of power.

[283] IT has been eſtabliſh'd as a certain principle, that general or abſtract ideas are nothing but individual ones taken in a certain light, and that, in reflecting on any object, 'tis as impoſſible to exclude from our thought all particular degrees of quantity and quality as from the real nature of things. If we be poſſeſt, therefore, of any idea of power in general, we muſt alſo be able to conceive ſome particular ſpecies of it; and as power cannot ſubſiſt alone, but is always regarded as an attribute of ſome being or exiſtence, we muſt be able to place this power in ſome particular being, and conceive that being as endow'd with a real force and energy, by which ſuch a particular effect neceſſarily re⯑ſults from its operation. We muſt diſtinct⯑ly and particularly conceive the connexion betwixt the cauſe and effect, and be able to pronounce, from a ſimple view of the one, that it muſt be follow'd or preceded by the other. This is the true manner of con⯑ceiving a particular power in a particular body: and a general idea being impoſſible without an individual; where the latter is impoſſible, 'tis certain the former can never exiſt. Now nothing is more evident, than that the human mind cannot form ſuch an idea of two objects, as to conceive any con⯑nexion [284] betwixt them, or comprehend di⯑ſtinctly that power or efficacy, by which they are united. Such a connexion wou'd amount to a demonſtration, and wou'd im⯑ply the abſolute impoſſibility for the one ob⯑ject not to follow, or to be conceiv'd not to follow upon the other: Which kind of connexion has already been rejected in all caſes. If any one is of a contrary opinion, and thinks he has attain'd a notion of power in any particular object, I deſire he may point out to me that object. But till I meet with ſuch-a-one, which I deſpair of, I can⯑not forbear concluding, that ſince we can never diſtinctly conceive how any particu⯑lar power can poſſibly reſide in any parti⯑cular object, we deceive ourſelves in ima⯑gining we can form any ſuch general idea.

THUS upon the whole we may infer, that when we talk of any being, whether of a ſu⯑perior or inferior nature, as endow'd with a power or force, proportion'd to any effect; when we ſpeak of a neceſſary connexion be⯑twixt objects, and ſuppoſe, that this conne⯑xion depends upon an efficacy or energy, with which any of theſe objects are endow'd; in all theſe expreſſions, ſo apply'd, we have really no diſtinct meaning, and make uſe [285] only of common words, without any clear and determinate ideas. But as 'tis more pro⯑bable, that theſe expreſſions do here loſe their true meaning by being wrong apply'd, than that they never have any meaning; 'twill be proper to beſtow another con⯑ſideration on this ſubject, to ſee if poſſibly we can diſcover the nature and origin of thoſe ideas, we annex to them.

SUPPOSE two objects to be preſented to us, of which the one is the cauſe and the other the effect; 'tis plain, that from the ſimple conſideration of one, or both theſe objects we never ſhall perceive the tie, by which they are united, or be able certainly to pronounce, that there is a connexion be⯑twixt them. 'Tis not, therefore, from any one inſtance, that we arrive at the idea of cauſe and effect, of a neceſſary connexion of power, of force, of energy, and of effi⯑cacy. Did we never ſee any but particular conjunctions of objects, entirely different from each other, we ſhou'd never be able to form any ſuch ideas.

BUT again; ſuppoſe we obſerve ſeveral in⯑ſtances, in which the ſame objects are always conjoin'd together, we immediately conceive a connexion betwixt them, and begin to draw an inference from one to another. This [286] multiplicity of reſembling inſtances, there⯑fore, conſtitutes the very eſſence of power or connexion, and is the ſource, from which the idea of it ariſes. In order, then, to underſtand the idea of power, we muſt con⯑ſider that multiplicity; nor do I aſk more to give a ſolution of that difficulty, which has ſo long perplex'd us. For thus I reaſon. The repetition of perfectly ſimilar inſtances can never alone give riſe to an original idea, different from what is to be found in any par⯑ticular inſtance, as has been obſerv'd, and as evidently follows from our fundamental principle, that all ideas are copy'd from im⯑preſſions. Since therefore the idea of power is a new original idea, not to be found in any one inſtance, and which yet ariſes from the repetition of ſeveral inſtances, it follows, that the repetition alone has not that effect, but muſt either diſcover or produce ſome⯑thing new, which is the ſource of that idea. Did the repetition neither diſcover nor pro⯑duce any thing new, our ideas might be multiply'd by it, but wou'd not be enlarg'd above what they are upon obſervation of one ſingle inſtance. Every enlargement, there⯑fore, (ſuch as the idea of power or con⯑nexion) which ariſes from the multiplicity of ſimilar inſtances, is copy'd from ſome [287] effects of the multiplicity, and will be per⯑fectly underſtood by underſtanding theſe effects. Wherever we find any thing new to be diſcover'd or produc'd by the repeti⯑tion, there we muſt place the power, and muſt never look for it in any other object.

BUT 'tis evident, in the firſt place, that the repetition of like objects in like relations of ſucceſſion and contiguity diſcovers no⯑thing new in any one of them; ſince we can draw no inference from it, nor make it a ſub⯑ject either of our demonſtrative or probable reaſonings;^* as has been already prov'd. Nay ſuppoſe we cou'd draw an inference, 'twou'd be of no conſequence in the preſent cauſe; ſince no kind of reaſoning can give riſe to a new idea, ſuch as this of power is; but wherever we reaſon, we muſt antece⯑dently be poſſeſt of clear ideas, which may be the objects of our reaſoning. The con⯑ception always precedes the underſtanding; and where the one is obſcure, the other is uncertain; where the one fails, the other muſt fail alſo.

SECONDLY, 'Tis certain that this repe⯑tition of ſimilar objects in ſimilar ſituations produces nothing new either in theſe objects, or in any external body. For 'twill readily be [288] allow'd, that the ſeveral inſtances we have of the conjunction of reſembling cauſes and effects are in themſelves entirely indepen⯑dent, and that the communication of mo⯑tion, which I ſee reſults at preſent from the ſhock of two billiard-balls, is totally diſtinct from that which I ſaw reſult from ſuch an impulſe a twelve-month ago. Theſe im⯑pulſes have no influence on each other. They are entirely divided by time and place; and the one might have exiſted and communi⯑cated motion, tho' the other never had been in being.

THERE is, then, nothing new either diſcover'd or produc'd in any objects by their conſtant conjunction, and by the uninter⯑rupted reſemblance of their relations of ſuc⯑ceſſion and contiguity. But 'tis from this reſemblance, that the ideas of neceſſity, of power, and of efficacy, are deriv'd. Theſe ideas, therefore, repreſent not any thing, that does or can belong to the objects, which are conſtantly conjoin'd. This is an argu⯑ment, which, in every view we can examine it, will be found perfectly unanſwerable. Similar inſtances are ſtill the firſt ſource of our idea of power or neceſſity; at the ſame time that they have no influence by their ſimi⯑larity either on each other, or on any external [289] object. We muſt therefore, turn ourſelves to ſome other quarter to ſeek the origin of that idea.

THO' the ſeveral reſembling inſtances, which give riſe to the idea of power, have no influence on each other, and can never produce any new quality in the object, which can be the model of that idea, yet the ob⯑ſervation of this reſemblance produces a new impreſſion in the mind, which is its real model. For after we have ob⯑ſerv'd the reſemblance in a ſufficient num⯑ber of inſtances, we immediately feel a de⯑termination of the mind to paſs from one object to its uſual attendant, and to con⯑ceive it in a ſtronger light upon account of that relation. This determination is the on⯑ly effect of the reſemblance; and therefore muſt be the ſame with power or efficacy, whoſe idea is deriv'd from the reſemblance. The ſeveral inſtances of reſembling conjunc⯑tions lead us into the notion of power and neceſſity. Theſe inſtances are in themſelves totally diſtinct from each other, and have no union but in the mind, which obſerves them, and collects their ideas. Neceſſity, then, is the effect of this obſervation, and is nothing but an internal impreſſion of the mind, or a determination to carry our [290] thoughts from one object to another. With⯑out conſidering it in this view, we can never arrive at the moſt diſtant notion of it, or be able to attribute it either to external or in⯑ternal objects, to ſpirit or body, to cauſes or effects.

THE neceſſary connexion betwixt cauſes and effects is the foundation of our infe⯑rence from one to the other. The foun⯑dation of our inference is the tranſition ari⯑ſing from the accuſtom'd union. Theſe are, therefore, the ſame.

THE idea of neceſſity ariſes from ſome impreſſion. There is no impreſſion con⯑vey'd by our ſenſes, which can give riſe to that idea. It muſt, therefore, be deriv'd from ſome internal impreſſion, or impreſſion of reflection. There is no internal impreſ⯑ſion, which has any relation to the preſent buſineſs, but that propenſity, which cuſ⯑tom produces, to paſs from an object to the idea of its uſual attendant. This therefore is the eſſence of neceſſity. Upon the whole, neceſſity is ſomething, that ex⯑iſts in the mind, not in objects; nor is it poſſible for us ever to form the moſt diſtant idea of it, conſider'd as a quality in bodies. Either we have no idea of neceſſity, or ne⯑ceſſity is nothing but that determination of [291] the thought to paſs from cauſes to effects and from effects to cauſes, according to their experienc'd union.

THUS as the neceſſity, which makes two times two equal to four, or three an⯑gles of a triangle equal to two right ones, lies only in the act of the underſtanding, by which we conſider and compare theſe ideas; in like manner the neceſſity or power, which unites cauſes and effects, lies in the deter⯑mination of the mind to paſs from the one to the other. The efficacy or energy of cauſes is neither plac'd in the cauſes themſelves, nor in the deity, nor in the concurrence of theſe two principles; but belongs entirely to the ſoul, which conſi⯑ders the union of two or more objects in all paſt inſtances. 'Tis here that the real power of cauſes is plac'd, along with their con⯑nexion and neceſſity.

I AM ſenſible, that of all the paradoxes, which I have had, or ſhall hereafter have occaſion to advance in the courſe of this treatiſe, the preſent one is the moſt violent, and that 'tis merely by dint of ſolid proof and reaſoning I can ever hope it will have admiſſion, and overcome the inveterate prejudices of mankind. Before we are re⯑concil'd to this doctrine, how often muſt [292] we repeat to ourſelves, that the ſimple view of any two objects or actions, however re⯑lated, can never give us any idea of power, or of a connexion betwixt them: that this idea ariſes from the repetition of their uni⯑on: that the repetition neither diſcovers nor cauſes any thing in the objects, but has an influence only on the mind, by that cuſ⯑tomary tranſition it produces: that this cuſ⯑tomary tranſition is, therefore, the ſame with the power and neceſſity; which are conſequently qualities of perceptions, not of objects, and are internally felt by the ſoul, and not perceiv'd externally in bodies? There is commonly an aſtoniſhment attend⯑ing every thing extraordinary; and this a⯑ſtoniſhment changes immediately into the higheſt degree of eſteem or contempt, ac⯑cording as we approve or diſapprove of the ſubject. I am much afraid, that tho' the fore⯑going reaſoning appears to me the ſhorteſt and moſt deciſive imaginable; yet with the generality of readers the biaſs of the mind will prevail, and give them a prejudice a⯑gainſt the preſent doctrine.

THIS contrary biaſs is eaſily accounted for. 'Tis a common obſervation, that the mind has a great propenſity to ſpread itſelf on external objects, and to conjoin with [293] them any internal impreſſions, which they occaſion, and which always make their ap⯑pearance at the ſame time that theſe ob⯑jects diſcover themſelves to the ſenſes. Thus as certain ſounds and ſmells are always found to attend certain viſible objects, we natural⯑ly imagine a conjunction, even in place, betwixt the objects and qualities, tho' the qualities be of ſuch a nature as to admit of no ſuch conjunction, and really exiſts no where. But of this more fully ^* hereafter. Mean while 'tis ſufficient to obſerve, that the ſame propenſity is the reaſon, why we ſup⯑poſe neceſſity and power to lie in the ob⯑jects we conſider, not in our mind, that conſiders them; notwithſtanding it is not poſſible for us to form the moſt diſtant idea of that quality, when it is not taken for the determination of the mind, to paſs from the idea of an object to that of its uſual at⯑tendant.

BUT tho' this be the only reaſonable account we can give of neceſſity, the con⯑trary notion is ſo riveted in the mind from the principles above-mention'd, that I doubt not but my ſentiments will be treated by many as extravagant and ridiculous. What! the efficacy of cauſes lie in the determi⯑nation [294] of the mind! As if cauſes did not operate entirely independent of the mind, and wou'd not continue their operation, e⯑ven tho' there was no mind exiſtent to con⯑template them, or reaſon concerning them. Thought may well depend on cauſes for its operation, but not cauſes on thought. This is to reverſe the order of nature, and make that ſecondary, which is really primary. To every operation there is a power propor⯑tion'd; and this power muſt be plac'd on the body, that operates. If we remove the power from one cauſe, we muſt aſcribe it to another: But to remove it from all cauſes, and beſtow it on a being, that is no ways related to the cauſe or effect, but by per⯑ceiving them, is a groſs abſurdity, and con⯑trary to the moſt certain principles of hu⯑man reaſon.

I CAN only reply to all theſe arguments, that the caſe is here much the ſame, as if a blind man ſhou'd pretend to find a great many abſurdities in the ſuppoſition, that the colour of ſcarlet is not the ſame with the ſound of a trumpet, nor light the ſame with ſolidity. If we have really no idea of a power or efficacy in any object, or of any real connexion betwixt cauſes and effects, 'twill be to little purpoſe to prove, that an [295] efficacy is neceſſary in all operations. We do not underſtand our own meaning in talking ſo, but ignorantly confound ideas, which are entirely diſtinct from each other. I am, indeed, ready to allow, that there may be ſeveral qualities both in material and immaterial objects, with which we are ut⯑terly unacquainted; and if we pleaſe to call theſe power or efficacy, 'twill be of little con⯑ſequence to the world. But when, inſtead of meaning theſe unknown qualities, we make the terms of power and efficacy ſigni⯑fy ſomething, of which we have a clear idea, and which is incompatible with thoſe objects, to which we apply it, obſcurity and error begin then to take place, and we are led aſtray by a falſe philoſophy. This is the caſe, when we transfer the determi⯑nation of the thought to external objects, and ſuppoſe any real intelligible connexion betwixt them; that being a quality, which can only belong to the mind that conſiders them.

As to what may be ſaid, that the ope⯑rations of nature are independent of our thought and reaſoning, I allow it; and ac⯑cordingly have obſerv'd, that objects bear to each other the relations of contiguity and ſucceſſion; that like objects may be obſerv'd [296] in ſeveral inſtances to have like relations; and that all this is independent of, and an⯑tecedent to the operations of the underſtand⯑ing. But if we go any farther, and aſcribe a power or neceſſary connexion to theſe ob⯑jects; this is what we can never obſerve in them, but muſt draw the idea of it from what we feel internally in contemplating them. And this I carry ſo far, that I am ready to convert my preſent reaſoning into an in⯑ſtance of it, by a ſubtility, which it will not be difficult to comprehend.

WHEN any object is preſented to us, it immediately conveys to the mind a live⯑ly idea of that object, which is uſually found to attend it; and this determination of the mind forms the neceſſary connexion of theſe objects. But when we change the point of view, from the objects to the perceptions; in that caſe the impreſſion is to be conſi⯑dered as the cauſe, and the lively idea as the effect; and their neceſſary connexion is that new determination, which we feel to paſs from the idea of the one to that of the other. The uniting principle among our in⯑ternal perceptions is as unintelligible as that among external objects, and is not known to us any other way than by experience. Now the nature and effects of experience have been [297] already ſufficiently examin'd and explain'd. It never gives us any inſight into the internal ſtructure or operating principle of objects, but only accuſtoms the mind to paſs from one to another.

'TIS now time to collect all the diffe⯑rent parts of this reaſoning, and by joining them together form an exact definition of the relation of cauſe and effect, which makes the ſubject of the preſent enquiry. This order wou'd not have been excuſable, of firſt examining our inference from the re⯑lation before we had explain'd the relation itſelf, had it been poſſible to proceed in a different method. But as the nature of the relation depends ſo much on that of the infe⯑rence, we have been oblig'd to advance in this ſeemingly propoſterous manner, and make uſe of terms before we were able exactly to define them, or fix their meaning. We ſhall now correct this fault by giving a pre⯑ciſe definition of cauſe and effect.

THERE may two definitions be given of this relation, which are only different, by their preſenting a different view of the ſame object, and making us conſider it either as a philoſophical or as a natural relation; either as a compariſon of two ideas, or as an aſſo⯑ciation betwixt them. We may define a [298] CAUSE to be ‘An object precedent and contiguous to another, and where all the objects reſembling the former are plac'd in like relations of precedency and conti⯑guity to thoſe objects, that reſemble the latter.’ If this definition be eſteem'd de⯑fective, becauſe drawn from objects foreign to the cauſe, we may ſubſtitute this other definition in its place, viz. ‘A CAUSE is an object precedent and contiguous to another, and ſo united with it, that the idea of the one determines the mind to form the idea of the other, and the im⯑preſſion of the one to form a more lively idea of the other.’ Shou'd this defini⯑tion alſo be rejected for the ſame reaſon, I know no other remedy, than that the perſons, who expreſs this delicacy, ſhou'd ſubſtitute a juſter definition in its place. But for my part I muſt own my incapacity for ſuch an undertaking. When I examine with the utmoſt accuracy thoſe objects, which are commonly denominated cauſes and ef⯑fects, I find, in conſidering a ſingle inſtance, that the one object is precedent and conti⯑guous to the other; and in inlarging my view to conſider ſeveral inſtances, I find only, that like objects are conſtantly plac'd in like relations of ſucceſſion and contiguity [299] Again, when I conſider the influence of this conſtant conjunction, I perceive, that ſuch a relation can never be an object of reaſon⯑ing, and can never operate upon the mind, but by means of cuſtom, which determines the imagination to make a tranſition from the idea of one object to that of its uſual attendant, and from the impreſſion of one to a more lively idea of the other. However extraordinary theſe ſentiments may appear, I think it fruitleſs to trouble myſelf with any farther enquiry or reaſoning upon the ſub⯑ject, but ſhall repoſe myſelf on them as on eſtabliſh'd maxims.

'TWILL only be proper, before we leave this ſubject, to draw ſome corrollaries from it, by which we may remove ſeveral pre⯑judices and popular errors, that have very much prevail'd in philoſophy. Firſt, We may learn from the foregoing doctrine, that all cauſes are of the ſame kind, and that in particular there is no foundation for that diſtinction, which we ſometimes make be⯑twixt efficient cauſes, and cauſes ſine qua non; or betwixt efficient cauſes, and formal, and material, and exemplary, and final cauſes. For as our idea of efficiency is deriv'd from the conſtant conjunction of two objects, where⯑ever this is obſerv'd, the cauſe is efficient; [300] and where it is not, there can never be a cauſe of any kind. For the ſame reaſon we muſt reject the diſtinction betwixt cauſe and occaſion, when ſuppos'd to ſignify any thing eſſentially different from each other. If con⯑ſtant conjunction be imply'd in what we call occaſion, 'tis a real cauſe. If not, 'tis no relation at all, and cannot give riſe to any argument or reaſoning.

SECONDLY, The ſame courſe of reaſon⯑ing will make us conclude, that there is but one kind of neceſſity, as there is but one kind of cauſe, and that the common diſ⯑tinction betwixt moral and phyſical neceſſity is without any foundation in nature. This clearly appears from the precedent explica⯑tion of neceſſity. 'Tis the conſtant con⯑junction of objects, along with the deter⯑mination of the mind, which conſtitutes a phyſical neceſſity: And the removal of theſe is the ſame thing with chance. As objects muſt either be conjoin'd or not, and as the mind muſt either be determin'd or not to paſs from one object to another, 'tis impoſſible to admit of any medium betwixt chance and an abſolute neceſſity. In weak⯑ening this conjunction and determination you do not change the nature of the neceſſity; ſince even in the operation of bodies, theſe [301] have different degrees of conſtancy and force, without producing a different ſpecies of that relation.

THE diſtinction, which we often make betwixt power and the exerciſe of it, is equally without foundation.

THIRDLY, We may now be able fully to overcome all that repugnance, which 'tis ſo natural for us to entertain againſt the foregoing reaſoning, by which we endea⯑vour'd to prove, that the neceſſity of a cauſe to every beginning of exiſtence is not founded on any arguments either demonſtrative or intuitive. Such an opinion will not appear ſtrange after the foregoing definitions. If we define a cauſe to be an object precedent and contiguous to another, and where all the objects reſembling the former are plac'd in a like relation of priority and contiguity to thoſe objects, that reſemble the latter; we may eaſily conceive, that there is no abſolute nor metaphyſical neceſſity, that every beginning of exiſtence ſhou'd be attended with ſuch an object. If we define a cauſe to be, An object precedent and contiguous to another, and ſo united with it in the imagination, that the idea of the one determines the mind to form the idea of the other, and the im⯑preſſion of the one to form a more lively idea [300] and where it is not, there can never be a cauſe of any kind. For the ſame reaſon we muſt reject the diſtinction betwixt cauſe and occaſion, when ſuppos'd to ſignify any thing eſſentially different from each other. If con⯑ſtant conjunction be imply'd in what we call occaſion, 'tis a real cauſe. If not, 'tis no relation at all, and cannot give riſe to any argument or reaſoning.

SECONDLY, The ſame courſe of reaſon⯑ing will make us conclude, that there is but one kind of neceſſity, as there is but one kind of cauſe, and that the common diſ⯑tinction betwixt moral and phyſical neceſſity is without any foundation in nature. This clearly appears from the precedent explica⯑tion of neceſſity. 'Tis the conſtant con⯑junction of objects, along with the deter⯑mination of the mind, which conſtitutes a phyſical neceſſity: And the removal of theſe is the ſame thing with chance. As objects muſt either be conjoin'd or not, and as the mind muſt either be determin'd or not to paſs from one object to another, 'tis impoſſible to admit of any medium betwixt chance and an abſolute neceſſity. In weak⯑ening this conjunction and determination you do not change the nature of the neceſſity; ſince even in the operation of bodies, theſe [301] have different degrees of conſtancy and force, without producing a different ſpecies of that relation.

THE diſtinction, which we often make betwixt power and the exerciſe of it, is equally without foundation.

THIRDLY, We may now be able fully to overcome all that repugnance, which 'tis ſo natural for us to entertain againſt the foregoing reaſoning, by which we endea⯑vour'd to prove, that the neceſſity of a cauſe to every beginning of exiſtence is not founded on any arguments either demonſtrative or intuitive. Such an opinion will not appear ſtrange after the foregoing definitions. If we define a cauſe to be an object precedent and contiguous to another, and where all the objects reſembling the former are plac'd in a like relation of priority and contiguity to thoſe objects, that reſemble the latter; we may eaſily conceive, that there is no abſolute nor metaphyſical neceſſity, that every beginning of exiſtence ſhou'd be attended with ſuch an object. If we define a cauſe to be, An object precedent and contiguous to another, and ſo united with it in the imagination, that the idea of the one determines the mind to form the idea of the other, and the im⯑preſſion of the one to form a more lively idea [302] of the other; we ſhall make ſtill leſs diffi⯑culty of aſſenting to this opinion. Such an influence on the mind is in itſelf perfectly extraordinary and incomprehenſible; nor can we be certain of its reality, but from ex⯑perience and obſervation.

I SHALL add as a fourth corrollary, that we can never have reaſon to believe that any object exiſts, of which we cannot form an idea. For as all our reaſonings concerning exiſtence are deriv'd from cauſation, and as all our reaſonings concerning cauſation are deriv'd from the experienc'd conjunction of objects, not from any reaſoning or reflec⯑tion, the ſame experience muſt give us a notion of theſe objects, and muſt remove all myſtery from our concluſions. This is ſo evident, that 'twou'd ſcarce have merited our attention, were it not to obviate certain ob⯑jections of this kind, which might ariſe a⯑gainſt the following reaſonings concerning matter and ſubſtance. I need not obſerve, that a full knowledge of the object is not requiſite, but only of thoſe qualities of it, which we believe to exiſt.

SECT. XV. Rules by which to judge of cauſes and effects.

ACCORDING to the precedent doc⯑trine, there are no objects, which by the mere ſurvey, without conſulting expe⯑rience, we can determine to be the cauſes of any other; and no objects, which we can certainly determine in the ſame manner not to be the cauſes. Any thing may produce any thing. Creation, annihilation, motion, reaſon, volition; all theſe may ariſe from one another, or from any other object we can imagine. Nor will this appear ſtrange, if we compare two principles explain'd above, that the conſtant conjunction of objects deter⯑mines their cauſation, and ^* that properly ſpeaking, no objects are contrary to each other, but exiſtence and non-exiſtence. Where objects are not contrary, nothing hinders them from having that conſtant conjunc⯑tion, on which the relation of cauſe and effect totally depends.

SINCE therefore 'tis poſſible for all ob⯑jects to become cauſes or effects to each [304] other, it may be proper to fix ſome general rules, by which we may know when they really are ſo.

1. THE cauſe and effect muſt be conti⯑guous in ſpace and time.

2. THE cauſe muſt be prior to the ef⯑fect.

3. THERE muſt be a conſtant union be⯑twixt the cauſe and effect. 'Tis chiefly this quality, that conſtitutes the relation.

4. THE ſame cauſe always produces the ſame effect, and the ſame effect never ariſes but from the ſame cauſe. This principle we derive from experience, and is the ſource of moſt of our philoſophical reaſonings. For when by any clear experiment we have diſ⯑cover'd the cauſes or effects of any phaeno⯑menon, we immediately extend our obſer⯑vation to every phaenomenon of the ſame kind, without waiting for that conſtant re⯑petition, from which the firſt idea of this relation is deriv'd.

5. THERE is another principle, which hangs upon this, viz. that where ſeveral different objects produce the ſame effect, it muſt be by means of ſome quality, which we diſcover to be common amongſt them. For as like effects imply like cauſes, we muſt always aſcribe the cauſation to the circum⯑ſtance, [305] wherein we diſcover the reſem⯑blance.

6. THE following principle is founded on the ſame reaſon. The difference in the effects of two reſembling objects muſt pro⯑ceed from that particular, in which they differ. For as like cauſes always produce like effects, when in any inſtance we find our expectation to be diſappointed, we muſt conclude that this irregularity proceeds from ſome difference in the cauſes.

7. WHEN any object encreaſes or dimi⯑niſhes with the encreaſe or diminution of its cauſe, 'tis to be regarded as a compounded effect, deriv'd from the union of the ſeveral different effects, which ariſe from the ſeveral different parts of the cauſe. The abſence or preſence of one part of the cauſe is here ſuppos'd to be always attended with the ab⯑ſence or preſence of a proportionable part of the effect. This conſtant conjunction ſuffi⯑ciently proves, that the one part is the cauſe of the other. We muſt, however, beware not to draw ſuch a concluſion from a few experiments. A certain degree of heat gives pleaſure; if you diminiſh that heat, the pleaſure diminiſhes; but it does not follow, that if you augment it be⯑yond a certain degree, the pleaſure will [306] likewiſe augment; for we find that it dege⯑nerates into pain.

8. THE eighth and laſt rule I ſhall take notice of is, that an object, which ex⯑iſts for any time in its full perfection with⯑out any effect, is not the ſole cauſe of that effect, but requires to be aſſiſted by ſome other principle, which may forward its in⯑fluence and operation. For as like effects neceſſarily follow from like cauſes, and in a contiguous time and place, their ſeparation for a moment ſhews, that theſe cauſes are not compleat ones.

HERE is all the LOGIC I think proper to employ in my reaſoning; and perhaps even this was not very neceſſary, but might have been ſupply'd by the natural principles of our underſtanding. Our ſcholaſtic head⯑pieces and logicians ſhew no ſuch ſuperi⯑ority above the mere vulgar in their reaſon and ability, as to give us any inclination to imitate them in delivering a long ſyſtem of rules and precepts to direct our judgment, in philoſophy. All the rules of this na⯑ture are very eaſy in their invention, but extremely difficult in their application; and even experimental philoſophy, which ſeems the moſt natural and ſimple of any, requires the utmoſt ſtretch of human judgment. [307] There is no phaenomenon in nature, but what is compounded and modify'd by ſo many different circumſtances, that in order to arrive at the deciſive point, we muſt carefully ſeparate whatever is ſuperfluous, and enquire by new experiments, if every particular circumſtance of the firſt experi⯑ment was eſſential to it. Theſe new expe⯑riments are liable to a diſcuſſion of the ſame kind; ſo that the utmoſt conſtancy is re⯑quir'd to make us perſevere in our enquiry, and the utmoſt ſagacity to chooſe the right way among ſo many that preſent themſelves. If this be the caſe even in natural philoſophy, how much more in moral, where there is a much greater complication of circumſtances, and where thoſe views and ſentiments, which are eſſential to any action of the mind, are ſo implicit and obſcure, that they often eſcape our ſtricteſt attention, and are not only unaccountable in their cauſes, but even unknown in their exiſtence? I am much a⯑fraid, leſt the ſmall ſucceſs I meet with in my enquiries will make this obſervation bear the air of an apology rather than of boaſt⯑ing.

IF any thing can give me ſecurity in this particular, 'twill be the enlarging the ſphere of my experiments as much as poſſible; for [308] which reaſon it may be proper in this place to examine the reaſoning faculty of brutes, as well as that of human creatures.

SECT. XVI. Of the reaſon of animals.

NEXT to the ridicule of denying an evident truth, is that of taking much pains to defend it; and no truth appears to me more evident, than that beaſts are endow'd with thought and reaſon as well as men. The arguments are in this caſe ſo obvious, that they never eſcape the moſt ſtupid and ignorant.

WE are conſcious, that we ourſelves, in adapting means to ends, are guided by rea⯑ſon and deſign, and that 'tis not ignorantly nor caſually we perform thoſe actions, which tend to ſelf-preſervation, to the obtaining pleaſure, and avoiding pain. When there⯑fore we ſee other creatures, in millions of inſtances, perform like actions, and direct them to like ends, all our principles of rea⯑ſon and probability carry us with an invin⯑cible force to believe the exiſtence of a like cauſe. 'Tis needleſs in my opinion to il⯑luſtrate this argument by the enumeration [309] of particulars. The ſmalleſt attention will ſupply us with more than are requiſite. The reſemblance betwixt the actions of animals and thoſe of men is ſo entire in this reſpect, that the very firſt action of the firſt animal we ſhall pleaſe to pitch on, will afford us an inconteſtable argument for the preſent doctrine.

THIS doctrine is as uſeful as it is obvious, and furniſhes us with a kind of touchſtone, by which we may try every ſyſtem in this ſpecies of philoſophy. 'Tis from the re⯑ſemblance of the external actions of animals to thoſe we ourſelves perform, that we judge their internal likewiſe to reſemble ours; and the ſame principle of reaſoning, carry'd one ſtep farther, will make us conclude that ſince our internal actions reſemble each other, the cauſes, from which they are deriv'd, muſt alſo be reſembling. When any hypotheſis, therefore, is advanc'd to explain a mental ope⯑ration, which is common to men and beaſts, we muſt apply the ſame hypotheſis to both; and as every true hypotheſis will abide this trial, ſo I may venture to affirm, that no falſe one will ever be able to endure it. The common defect of thoſe ſyſtems, which philoſophers have employ'd to account for the actions of the mind, is, that they ſup⯑poſe [310] ſuch a ſubtility and refinement of thought, as not only exceeds the capacity of mere animals, but even of children and the common people in our own ſpecies; who are notwithſtanding ſuſceptible of the ſame emotions and affections as perſons of the moſt accompliſh'd genius and underſtanding. Such a ſubtility is a clear proof of the falſhood, as the contrary ſimplicity of the truth, of any ſyſtem.

LET us therefore put our preſent ſyſtem concerning the nature of the underſtanding to this deciſive trial, and ſee whether it will equally account for the reaſonings of beaſts as for theſe of the human ſpecies.

HERE we muſt make a diſtinction be⯑twixt thoſe actions of animals, which are of a vulgar nature, and ſeem to be on a level with their common capacities, and thoſe more extraordinary inſtances of ſagacity, which they ſometimes diſcover for their own preſervation, and the propagation of their ſpecies. A dog, that avoids fire and preci⯑pices, that ſhuns ſtrangers, and careſſes his maſter, affords us an inſtance of the firſt kind. A bird, that chooſes with ſuch care and nicety the place and materials of her neſt, and ſits upon her eggs for a due time, and in a ſuitable ſeaſon, with all the pre⯑caution [311] that a chymiſt is capable of in the moſt delicate projection, furniſhes us with a lively inſtance of the ſecond.

AS to the former actions, I aſſert they proceed from a reaſoning, that is not in it⯑ſelf different, nor founded on different prin⯑ciples, from that which appears in hu⯑man nature. 'Tis neceſſary in the firſt place, that there be ſome impreſſion im⯑mediately preſent to their memory or ſenſes, in order to be the foundation of their judg⯑ment. From the tone of voice the dog in⯑fers his maſter's anger, and foreſees his own puniſhment. From a certain ſenſation af⯑fecting his ſmell, he judges his game not to be far diſtant from him.

SECONDLY, The inference he draws from the preſent impreſſion is built on ex⯑perience, and on his obſervation of the con⯑junction of objects in paſt inſtances. As you vary this experience, he varies his reaſoning. Make a beating follow upon one ſign or motion for ſome time, and afterwards upon another; and he will ſucceſſively draw dif⯑ferent concluſions, according to his moſt re⯑cent experience.

NOW let any philoſopher make a trial, and endeavour to explain that act of the mind, which we call belief, and give an ac⯑count [312] of the principles, from which it is deriv'd, independent of the influence of cuſ⯑tom on the imagination, and let his hypo⯑theſis be equally applicable to beaſts as to the human ſpecies; and after he has done this, I promiſe to embrace his opinion. But at the ſame time I demand as an equitable condition, that if my ſyſtem be the only one, which can anſwer to all theſe terms, it may be receiv'd as entirely ſatisfactory and convincing. And that 'tis the only one, is evident almoſt without any reaſoning. Beaſts certainly never perceive any real con⯑nexion among objects. 'Tis therefore by experience they infer one from another. They can never by any arguments form a general concluſion, that thoſe objects, of which they have had no experience, re⯑ſemble thoſe of which they have. 'Tis there⯑fore by means of cuſtom alone, that experi⯑ence operates upon them. All this was ſuffici⯑ently evident with reſpect to man. But with reſpect to beaſts there cannot be the leaſt ſuſpicion of miſtake; which muſt be own'd to be a ſtrong confirmation, or rather an invincible proof of my ſyſtem.

NOTHING ſhews more the force of ha⯑bit in reconciling us to any phaenomenon, than this, that men are not aſtoniſh'd at the ope⯑rations [313] of their own reaſon, at the ſame time, that they admire the inſtinct of ani⯑mals, and find a difficulty in explaining it, merely becauſe it cannot be reduc'd to the very ſame principles. To conſider the mat⯑ter aright, reaſon is nothing but a wonder⯑ful and unintelligible inſtinct in our ſouls, which carries us along a certain train of ideas, and endows them with particular qua⯑lities, according to their particular ſituations and relations. This inſtinct, 'tis true, ariſes from paſt obſervation and experience; but can any one give the ultimate reaſon, why paſt experience and obſervation produces ſuch an effect, any more than why nature alone ſhou'd produce it? Nature may cer⯑tainly produce whatever can ariſe from ha⯑bit: Nay, habit is nothing but one of the principles of nature, and derives all its force from that origin.

SECT. I. Of ſcepticiſm with regard to reaſon.

IN all demonſtrative ſciences the rules are certain and infallible; but when we apply them, our fallible and uncertain faculties are very apt to depart from them, and fall into error. We muſt, therefore, in every reaſoning form a new judgment, as a check or con⯑troul on our firſt judgment or belief; and muſt enlarge our view to comprehend a kind of hiſtory of all the inſtances, where⯑in our underſtanding has deceiv'd us, com⯑par'd with thoſe, wherein its teſtimony was juſt and true. Our reaſon muſt be conſi⯑ſider'd [316] as a kind of cauſe, of which truth is the natural effect; but ſuch-a-one as by the irruption of other cauſes, and by the incon⯑ſtancy of our mental powers, may frequent⯑ly be prevented. By this means all know⯑ledge degenerates into probability; and this probability is greater or leſs, according to our experience of the veracity or deceitful⯑neſs of our underſtanding, and according to the ſimplicity or intricacy of the queſtion.

THERE is no Algebraiſt nor Mathema⯑tician ſo expert in his ſcience, as to place entire confidence in any truth immediately upon his diſcovery of it, or regard it as any thing, but a mere probability. Every time he runs over his proofs, his confidence en⯑creaſes; but ſtill more by the approbation of his friends; and is rais'd to its utmoſt perfection by the univerſal aſſent and ap⯑plauſes of the learned world. Now 'tis evident, that this gradual encreaſe of aſſu⯑rance is nothing but the addition of new probabilities, and is deriv'd from the con⯑ſtant union of cauſes and effects, according to paſt experience and obſervation.

IN accompts of any length or impor⯑tance, Merchants ſeldom truſt to the infal⯑lible certainty of numbers for their ſecurity; but by the artificial ſtructure of the accompts, [317] produce a probability beyond what is de⯑riv'd from the ſkill and experience of the accomptant. For that is plainly of itſelf ſome degree of probability; tho' uncertain and variable, according to the degrees of his experience and length of the accompt. Now as none will maintain, that our aſſurance in a long numeration exceeds probability, I may ſafely affirm, that there ſcarce is any propoſition concerning numbers, of which we can have a fuller ſecurity. For 'tis eaſi⯑ly poſſible, by gradually diminiſhing the numbers, to reduce the longeſt ſeries of ad⯑dition to the moſt ſimple queſtion, which can be form'd, to an addition of two ſingle numbers; and upon this ſuppoſi⯑tion we ſhall find it impracticable to ſhew the preciſe limits of knowledge and of pro⯑bability, or diſcover that particular num⯑ber, at which the one ends and the other begins. But knowledge and probability are of ſuch contrary and diſagreeing natures, that they cannot well run inſenſibly into each o⯑ther, and that becauſe they will not divide, but muſt be either entirely preſent, or en⯑tirely abſent. Beſides, if any ſingle addi⯑tion were certain, every one wou'd be ſo, and conſequently the whole or total ſum; unleſs the whole can be different from all [318] its parts. I had almoſt ſaid, that this was certain; but I reflect, that it muſt reduce itſelf, as well as every other reaſoning, and from knowledge degenerate into probabi⯑lity.

SINCE therefore all knowledge reſolves itſelf into probability, and becomes at laſt of the ſame nature with that evidence, which we employ in common life, we muſt now examine this latter ſpecies of reaſoning, and ſee on what foundation it ſtands.

IN every judgment, which we can form concerning probability, as well as concern⯑ing knowledge, we ought always to correct the firſt judgment, deriv'd from the nature of the object, by another judgment, deriv'd from the nature of the underſtanding. 'Tis certain a man of ſolid ſenſe and long ex⯑perience ought to have, and uſually has, a greater aſſurance in his opinions, than one that is fooliſh and ignorant, and that our ſentiments have different degrees of autho⯑rity, even with ourſelves, in proportion to the degrees of our reaſon and experience. In the man of the beſt ſenſe and longeſt ex⯑perience, this authority is never entire; ſince even ſuch-a-one muſt be conſcious of many errors in the paſt, and muſt ſtill dread the like for the future. Here then ariſes a new [319] ſpecies of probability to correct and regulate the firſt, and fix its juſt ſtandard and pro⯑portion. As demonſtration is ſubject to the controul of probability, ſo is probability li⯑able to a new correction by a reflex act of the mind, wherein the nature of our under⯑ſtanding, and our reaſoning from the firſt probability become our objects.

HAVING thus found in every probability, beſide the original uncertainty inherent in the ſubject, a new uncertainty deriv'd from the weakneſs of that faculty, which judges, and having adjuſted theſe two together, we are oblig'd by our reaſon to add a new doubt deriv'd from the poſſibility of error in the eſtimation we make of the truth and fidelity of our faculties. This is a doubt, which immediately occurs to us, and of which, if we wou'd cloſely purſue our rea⯑ſon, we cannot avoid giving a deciſion. But this deciſion, tho' it ſhou'd be favourable to our preceeding judgment, being founded only on probability, muſt weaken ſtill fur⯑ther our firſt evidence, and muſt itſelf be weaken'd by a fourth doubt of the ſame kind, and ſo on in infinitum; till at laſt there remain nothing of the original proba⯑bility, however great we may ſuppoſe it to have been, and however ſmall the diminu⯑tion [320] by every new uncertainty. No finite object can ſubſiſt under a decreaſe repeated in infinitum; and even the vaſteſt quanity, which can enter into human imagination, muſt in this manner be reduc'd to nothing. Let our firſt belief be never ſo ſtrong, it muſt infallibly periſh by paſſing thro' ſo many new examinations, of which each di⯑miniſhes ſomewhat of its force and vigour. When I reflect on the natural fallibility of my judgment, I have leſs confidence in my opinions, than when I only conſider the ob⯑jects concerning which I reaſon; and when I proceed ſtill farther, to turn the ſcrutiny againſt every ſucceſſive eſtimation I make of my faculties, all the rules of logic re⯑quire a continual diminution, and at laſt a total extinction of belief and evidence.

SHOU'D it here be aſk'd me, whether I ſincerely aſſent to this argument, which I ſeem to take ſuch pains to inculcate, and whether I be really one of thoſe ſceptics, who hold that all is uncertain, and that our judgment is not in any thing poſſeſt of any meaſures of truth and falſhood; I ſhou'd reply, that this queſtion is entirely ſuperfluous, and that neither I, nor any other perſon was ever ſincerely and conſtantly of that opinion. Na⯑ture, by an abſolute and uncontroulable ne⯑ceſſity [321] has determin'd us to judge as well as to breathe and feel; nor can we any more forbear viewing certain objects in a ſtronger and fuller light, upon account of their cuſtomary connexion with a preſent impreſſion, than we can hinder ourſelves from thinking as long as we are awake, or ſeeing the ſurrounding bodies, when we turn our eyes towards them in broad ſun⯑ſhine. Whoever has taken the pains to re⯑fute the cavils of this total ſcepticiſm, has really diſputed without an antagoniſt, and endeavour'd by arguments to eſtabliſh a fa⯑culty, which nature has antecedently im⯑planted in the mind, and render'd unavoid⯑able.

MY intention then in diſplaying ſo care⯑fully the arguments of that fantaſtic ſect, is only to make the reader ſenſible of the truth of my hypotheſis, that all our rea⯑ſonings concerning cauſes and effects are de⯑riv'd from nothing but cuſtom; and that be⯑lief is more properly an act of the ſenſitive, than of the cogitative part of our natures. I have here prov'd, that the very ſame prin⯑ciples, which make us form a deciſion up⯑on any ſubject, and correct that deciſion by the conſideration of our genius and capaci⯑ty, and of the ſituation of our mind, when [322] we examin'd that ſubject; I ſay, I have prov'd, that theſe ſame principles, when carry'd farther, and apply'd to every new reflex judgment, muſt, by continually diminiſhing the original evidence, at laſt reduce it to nothing, and utterly ſubvert all belief and o⯑pinion. If belief, therefore, were a ſimple act of the thought, without any peculiar man⯑ner of conception, or the addition of a force and vivacity, it muſt infallibly deſtroy it⯑ſelf, and in every caſe terminate in a total ſuſpenſe of judgment. But as experience will ſufficiently convince any one, who thinks it worth while to try, that tho' he can find no error in the foregoing argu⯑ments, yet he ſtill continues to believe, and think, and reaſon as uſual, he may ſafely conclude, that his reaſoning and belief is ſome ſenſation or peculiar manner of con⯑ception, which 'tis impoſſible for mere ideas and reflections to deſtroy.

BUT here, perhaps, it may be demand⯑ed, how it happens, even upon my hypo⯑theſis, that theſe arguments above-explain'd produce not a total ſuſpenſe of judgment, and after what manner the mind ever re⯑tains a degree of aſſurance in any ſubject? For as theſe new probabilities, which by their repetition perpetually diminiſh the ori⯑ginal [323] evidence, are founded on the very ſame principles, whether of thought or ſen⯑ſation, as the primary judgment, it may ſeem unavoidable, that in either caſe they muſt equally ſubvert it, and by the oppo⯑ſition, either of contrary thoughts or ſenſa⯑tions, reduce the mind to a total uncertain⯑ty. I ſuppoſe, there is ſome queſtion pro⯑pos'd to me, and that after revolving over the impreſſions of my memory and ſenſes, and carrying my thoughts from them to ſuch objects, as are commonly conjoin'd with them, I feel a ſtronger and more for⯑cible conception on the one ſide, than on the other. This ſtrong conception forms my firſt deciſion. I ſuppoſe, that afterwards I examine my judgment itſelf, and obſerving from experience, that 'tis ſometimes juſt and ſometimes erroneous, I conſider it as regu⯑lated by contrary principles or cauſes, of which ſome lead to truth, and ſome to er⯑ror; and in ballancing theſe contrary cauſes, I diminiſh by a new probability the aſſu⯑rance of my firſt deciſion. This new pro⯑bability is liable to the ſame diminution as the foregoing, and ſo on, in infinitum. 'Tis therefore demanded, how it happens, that even after all we retain a degree of belief, [324] which is ſufficient for our purpoſe, either in philoſophy or common life.

I ANSWER, that after the firſt and ſe⯑cond deciſion; as the action of the mind becomes forc'd and unnatural, and the ideas faint and obſcure; tho' the principles of judgment, and the ballancing of oppoſite cauſes be the ſame as at the very beginning; yet their influence on the imagination, and the vigour they add to, or diminiſh from the thought, is by no means equal. Where the mind reaches not its objects with ea⯑ſineſs and facility, the ſame principles have not the ſame effect as in a more na⯑tural conception of the ideas; nor does the imagination feel a ſenſation, which holds any proportion with that which ariſes from its common judgments and opinions. The attention is on the ſtretch: The poſture of the mind is uneaſy; and the ſpirits being diverted from their natural courſe, are not govern'd in their movements by the ſame laws, at leaſt not to the ſame degree, as when they flow in their uſual channel.

IF we deſire ſimilar inſtances, 'twill not be very difficult to find them. The preſent ſubject of metaphyſics will ſupply us abun⯑dantly. The ſame argument, which wou'd have been eſteem'd convincing in a reaſoning [325] concerning hiſtory or politics, has little or no influence in theſe abſtruſer ſubjects, even tho' it be perfectly comprehended; and that becauſe there is requir'd a ſtudy and an ef⯑fort of thought, in order to its being com⯑prehended: And this effort of thought di⯑ſturbs the operation of our ſentiments, on which the belief depends. The caſe is the ſame in other ſubjects. The ſtraining of the imagination always hinders the regular flow⯑ing of the paſſions and ſentiments. A tra⯑gic poet, that wou'd repreſent his heroes as very ingenious and witty in their misfor⯑tunes, wou'd never touch the paſſions. As the emotions of the ſoul prevent any ſubtile reaſoning and reflection, ſo theſe latter ac⯑tions of the mind are equally prejudicial to the former. The mind, as well as the bo⯑dy, ſeems to be endow'd with a certain pre⯑ciſe degree of force and activity, which it never employs in one action, but at the ex⯑pence of all the reſt. This is more evident⯑ly true, where the actions are of quite dif⯑ferent natures; ſince in that caſe the force of the mind is not only diverted, but even the diſpoſition chang'd, ſo as render us in⯑capable of a ſudden tranſition from one ac⯑tion to the other, and ſtill more of per⯑forming both at once. No wonder, then, [326] the conviction, which ariſes from a ſubtile reaſoning, diminiſhes in proportion to the efforts, which the imagination makes to en⯑ter into the reaſoning, and to conceive it in all its parts. Belief, being a lively concep⯑tion, can never be entire, where it is not founded on ſomething natural and eaſy.

THIS I take to be the true ſtate of the queſtion, and cannot approve of that expedi⯑tious way, which ſome take with the ſcep⯑tics, to reject at once all their arguments without enquiry or examination. If the ſceptical reaſonings be ſtrong, ſay they, 'tis a proof, that reaſon may have ſome force and authority: if weak, they can never be ſuffi⯑cient to invalidate all the concluſions of our underſtanding. This argument is not juſt; becauſe the ſceptical reaſonings, were it poſ⯑ſible for them to exiſt, and were they not deſtroy'd by their ſubtility, wou'd be ſuc⯑ceſſively both ſtrong and weak, according to the ſucceſſive diſpoſitions of the mind. Reaſon firſt appears in poſſeſſion of the throne, preſcribing laws, and impoſing max⯑ims, with an abſolute ſway and authority. Her enemy, therefore, is oblig'd to take ſhelter under her protection, and by make⯑ing uſe of rational arguments to prove the fallaciouſneſs and imbecility of reaſon, pro⯑duces, [327] in a manner, a patent under her hand and ſeal. This patent has at firſt an authority, proportion'd to the preſent and immediate authority of reaſon, from which it is deriv'd. But as it is ſuppos'd to be contradictory to reaſon, it gradually dimi⯑niſhes the force of that governing power, and its own at the ſame time; till at laſt they both vaniſh away into nothing, by a regu⯑lar and juſt diminution. The ſceptical and dogmatical reaſons are of the ſame kind, tho' contrary in their operation and tendency; ſo that where the latter is ſtrong, it has an enemy of equal force in the former to encounter; and as their forces were at firſt equal, they ſtill continue ſo, as long as either of them ſubſiſts; nor does one of them loſe any force in the conteſt, without taking as much from its antagoniſt. 'Tis happy, therefore, that nature breaks the force of all ſceptical arguments in time, and keeps them from having any conſiderable influence on the underſtanding. Were we to truſt en⯑tirely to their ſelf-deſtruction, that can ne⯑ver take place, 'till they have firſt ſubverted all conviction, and have totally deſtroy'd human reaſon.

SECT. II. Of ſcepticiſm with regard to the ſenſes.

THUS the ſceptic ſtill continues to reaſon and believe, even tho' he aſ⯑ſerts, that he cannot defend his reaſon by reaſon; and by the ſame rule he muſt aſſent to the principle concerning the exiſtence of body, tho' he cannot pretend by any argu⯑ments of philoſophy to maintain its veracity. Nature has not left this to his choice, and has doubtleſs eſteem'd it an affair of too great importance to be truſted to our uncertain reaſonings and ſpeculations. We may well aſk, What cauſes induce us to be⯑lieve in the exiſtence of body? but 'tis in vain to aſk, Whether there be body or not? That is a point, which we muſt take for granted in all our reaſonings.

THE ſubject, then, of our preſent en⯑quiry is concerning the cauſes which induce us to believe in the exiſtence of body: And my reaſonings on this head I ſhall begin with a diſtinction, which at firſt ſight may ſeem ſuperfluous, but which will contribute very much to the perfect underſtanding of [329] what follows. We ought to examine apart thoſe two queſtions, which are commonly confounded together, viz. Why we attri⯑bute a CONTINU'D exiſtence to objects, even when they are not preſent to the ſen⯑ſes; and why we ſuppoſe them to have an exiſtence DISTINCT from the mind and perception. Under this laſt head I compre⯑hend their ſituation as well as relations, their external poſition as well as the inde⯑pendence of their exiſtence and operation. Theſe two queſtions concerning the con⯑tinu'd and diſtinct exiſtence of body are intimately connected together. For if the objects of our ſenſes continue to exiſt, even when they are not perceiv'd, their exiſtence is of courſe independent of and diſtinct from the perception; and vice verſa, if their ex⯑iſtence be independent of the perception and diſtinct from it, they muſt continue to exiſt, even tho' they be not perceiv'd. But tho' the deciſion of the one queſtion decides the other; yet that we may the more eaſily diſ⯑cover the principles of human nature, from whence the deciſion ariſes, we ſhall carry along with us this diſtinction, and ſhall conſider, whether it be the ſenſes, rea⯑ſon, or the imagination, that produces the opinion of a continu'd or of a diſtinct exiſ⯑tence. [330] Theſe are the only queſtions, that are intelligible on the preſent ſubject. For as to the notion of external exiſtence, when taken for ſomething ſpecifically different from our perceptions,^* we have already ſhewn its abſurdity.

TO begin with the SENSES, 'tis evident theſe faculties are incapable of giving riſe to the notion of the continu'd exiſtence of their objects, after they no longer appear to the ſenſes. For that is a contradiction in terms, and ſuppoſes that the ſenſes continue to operate, even after they have ceas'd all manner of operation. Theſe fa⯑culties, therefore, if they have any influ⯑ence in the preſent caſe, muſt produce the opinion of a diſtinct, not of a con⯑tinu'd exiſtence; and in order to that, muſt preſent their impreſſions either as ima⯑ges and repreſentations, or as theſe very diſ⯑tinct and external exiſtences.

THAT our ſenſes offer not their impreſ⯑ſions as the images of ſomething diſtinct, or independent, and external, is evident; becauſe they convey to us nothing but a ſingle per⯑ception, and never give us the leaſt inti⯑mation of any thing beyond. A ſingle per⯑ception can never produce the idea of a [331] double exiſtence, but by ſome inference either of the reaſon or imagination. When the mind looks farther than what imme⯑diately appears to it, its concluſions can never be put to the account of the ſenſes; and it certainly looks farther, when from a ſingle perception it infers a double exiſtence, and ſuppoſes the relations of reſemblance and cauſation betwixt them.

IF our ſenſes, therefore, ſuggeſt any idea of diſtinct exiſtences, they muſt convey the impreſſions as thoſe very exiſtences, by a kind of fallacy and illuſion. Upon this head we may obſerve, that all ſenſations are felt by the mind, ſuch as they really are, and that when we doubt, whether they preſent themſelves as diſtinct objects, or as mere impreſſions, the difficulty is not con⯑cerning their nature, but concerning their relations and ſituation. Now if the ſenſes preſented our impreſſions as external to, and independent of ourſelves, both the objects and ourſelves muſt be obvious to our ſenſes, otherwiſe they cou'd not be compar'd by theſe faculties. The difficulty, then, is how far we are ourſelves the objects of our ſenſes.

'TIS certain there is no queſtion in phi⯑loſophy more abſtruſe than that concerning identity, and the nature of the uniting prin⯑ciple, [332] which conſtitutes a perſon. So far from being able by our ſenſes merely to de⯑termine this queſtion, we muſt have recourſe to the moſt profound metaphyſics to give a ſatisfactory anſwer to it; and in com⯑mon life 'tis evident theſe ideas of ſelf and perſon are never very fix'd nor determinate. 'Tis abſurd, therefore, to imagine the ſenſes can ever diſtinguiſh betwixt ourſelves and external objects.

ADD to this, that every impreſſion, ex⯑ternal and internal, paſſions, affections, ſen⯑ſations, pains and pleaſures, are originally on the ſame footing; and that whatever other differences we may obſerve among them, they appear, all of them, in their true colours, as impreſſions or perceptions. And indeed, if we conſider the matter aright, 'tis ſcarce poſſible it ſhou'd be otherwiſe, nor is it conceivable that our ſenſes ſhou'd be more capable of deceiving us in the ſituation and relations, than in the nature of our impreſ⯑ſions. For ſince all actions and ſenſations of the mind are known to us by conſciouſ⯑neſs, they muſt neceſſarily appear in every particular what they are, and be what they appear. Every thing that enters the mind, being in reality as the perception, 'tis impoſſi⯑ble any thing ſhou'd to feeling appear dif⯑ferent. [333] This were to ſuppoſe, that even where we are moſt intimately conſcious, we might be miſtaken.

BUT not to loſe time in examining, whe⯑ther 'tis poſſible for our ſenſes to deceive us, and repreſent our perceptions as diſtinct from ourſelves, that is as external to and indepen⯑dent of us; let us conſider whether they re⯑ally do ſo, and whether this error proceeds from an immediate ſenſation, or from ſome other cauſes.

TO begin with the queſtion concerning external exiſtence, it may perhaps be ſaid, that ſetting aſide the metaphyſical queſtion of the identity of a thinking ſubſtance, our own body evidently belongs to us; and as ſeveral impreſſions appear exterior to the body, we ſuppoſe them alſo exterior to our⯑ſelves. The paper, on which I write at preſent, is beyond my hand. The table is beyond the paper. The walls of the cham⯑ber beyond the table. And in caſting my eye towards the window, I perceive a great extent of fields and buildings beyond my chamber. From all this it may be infer'd, that no other faculty is requir'd, beſide the ſenſes, to convince us of the external exiſ⯑tence of body. But to prevent this in⯑ference, we need only weigh the three [334] following conſiderations. Firſt, That, pro⯑perly ſpeaking, 'tis not our body we perceive, when we regard our limbs and members, but certain impreſſions, which enter by the ſenſes; ſo that the aſcribing a real and cor⯑poreal exiſtence to theſe impreſſions, or to their objects, is an act of the mind as diffi⯑cult to explain, as that which we examine at preſent. Secondly, Sounds, and taſtes, and ſmells, tho' commonly regarded by the mind as continu'd independent qualities, appear not to have any exiſtence in extenſion, and conſequently cannot appear to the ſenſes as ſituated externally to the body. The rea⯑ſon, why we aſcribe a place to them, ſhall be conſider'd ^* afterwards. Thirdly, Even our ſight informs us not of diſtance or out⯑neſs (ſo to ſpeak) immediately and without a certain reaſoning and experience, as is ac⯑knowledg'd by the moſt rational philoſo⯑phers.

AS to the independency of our perceptions on ourſelves, this can never be an object of the ſenſes; but any opinion we form con⯑cerning it, muſt be deriv'd from experience and obſervation: And we ſhall ſee after⯑wards, that our concluſions from experience are far from being favourable to the doctrine of [335] the independency of our perceptions. Mean while we may obſerve that when we talk of real diſtinct exiſtences, we have commonly more in our eye their independency than external ſituation in place, and think an object has a ſufficient reality, when its Being is uninterrupted, and independent of the in⯑ceſſant revolutions, which we are conſcious of in ourſelves.

THUS to reſume what I have ſaid con⯑cerning the ſenſes; they give us no notion of continu'd exiſtence, becauſe they cannot operate beyond the extent, in which they really operate. They as little produce the opinion of a diſtinct exiſtence, becauſe they neither can offer it to the mind as repre⯑ſented, nor as original. To offer it as re⯑preſented, they muſt preſent both an object and an image. To make it appear as ori⯑ginal, they muſt convey a falſhood; and this falſhood muſt lie in the relations and ſituation: In order to which they muſt be able to compare the object with ourſelves; and even in that caſe they do not, nor is it poſſible they ſhou'd, deceive us. We may, therefore, conclude with certainty, that the opinion of a continu'd and of a diſtinct ex⯑iſtence never ariſes from the ſenſes.

[336] TO confirm this we may obſerve, that there are three different kinds of impreſſions convey'd by the ſenſes. The firſt are thoſe of the figure, bulk, motion and ſolidity of bodies. The ſecond thoſe of colours, taſtes, ſmells, ſounds, heat and cold. The third are the pains and pleaſures, that ariſe from the application of objects to our bodies, as by the cutting of our fleſh with ſteel, and ſuch like. Both philoſophers and the vul⯑gar ſuppoſe the firſt of theſe to have a di⯑ſtinct continu'd exiſtence. The vulgar only regard the ſecond as on the ſame footing. Both philoſophers and the vulgar, again, eſteem the third to be merely perceptions; and conſequently interrupted and dependent beings.

NOW 'tis evident, that, whatever may be our philoſophical opinion, colours, ſounds, heat and cold, as far as appears to the ſenſes, exiſt after the ſame manner with motion and ſolidity, and that the difference we make betwixt them in this reſpect, ariſes not from the mere perception. So ſtrong is the prejudice for the diſtinct continu'd exiſt⯑ence of the former qualities, that when the contrary opinion is advanc'd by modern phi⯑loſophers, people imagine they can almoſt refute it from their feeling and experience, [337] and that their very ſenſes contradict this philoſophy. 'Tis alſo evident, that colours, ſounds, &c. are originally on the ſame foot⯑ing with the pain that ariſes from ſteel, and pleaſure that proceeds from a fire; and that the difference betwixt them is founded nei⯑ther on perception nor reaſon, but on the imagination. For as they are confeſt to be, both of them, nothing but perceptions ariſing from the particular configurations and mo⯑tions of the parts of body, wherein poſſibly can their difference conſiſt? Upon the whole, then, we may conclude, that as far as the ſenſes are judges, all perceptions are the ſame in the manner of their exiſtence.

WE may alſo obſerve in this inſtance of ſounds and colours, that we can attribute a diſtinct continu'd exiſtence to objects with⯑out ever conſulting REASON, or weighing our opinions by any philoſophical principles. And indeed, whatever convincing arguments philoſophers may fancy they can produce to eſtabliſh the belief of objects independent of the mind, 'tis obvious theſe arguments are known but to very few, and that 'tis not by them, that children, peaſants, and the greateſt part of mankind are induc'd to attribute objects to ſome impreſſions, and deny them to others. Accordingly we find, [338] that all the concluſions, which the vul⯑gar form on this head, are directly con⯑trary to thoſe, which are confirm'd by phi⯑loſophy. For philoſophy informs us, that every thing, which appears to the mind, is nothing but a perception, and is interrupted, and dependent on the mind; whereas the vulgar confound perceptions and objects, and attribute a diſtinct continu'd exiſtence to the very things they feel or ſee. This ſentiment, then, as it is entirely unreaſon⯑ſonable, muſt proceed from ſome other fa⯑culty than the underſtanding. To which we may add, that as long as we take our perceptions and objects to be the ſame, we can never infer the exiſtence of the one from that of the other, nor form any ar⯑gument from the relation of cauſe and ef⯑fect; which is the only one that can aſſure us of matter of fact. Even after we di⯑ſtinguiſh our perceptions from our objects, 'twill appear preſently, that we are ſtill in⯑capable of reaſoning from the exiſtence of one to that of the other: So that upon the whole our reaſon neither does, nor is it poſ⯑ſible it ever ſhou'd, upon any ſuppoſition, give us an aſſurance of the continu'd and diſtinct exiſtence of body. That opinion muſt be entirely owing to the IMAGINA⯑TION: [339] which muſt now be the ſubject of our enquiry.

SINCE all impreſſions are internal and periſhing exiſtences, and appear as ſuch, the notion of their diſtinct and continu'd exiſtence muſt ariſe from a concurrence of ſome of their qualities with the qualities of the imagination; and ſince this notion does not extend to all of them, it muſt ariſe from certain qualities peculiar to ſome im⯑preſſions. 'Twill therefore be eaſy for us to diſcover theſe qualities by a compariſon of the impreſſions, to which we attribute a diſtinct and continu'd exiſtence, with thoſe, which we regard as internal and periſhing.

WE may obſerve, then, that 'tis neither upon account of the involuntarineſs of cer⯑tain impreſſions, as is commonly ſuppos'd, nor of their ſuperior force and violence, that we attribute to them a reality, and con⯑tinu'd exiſtence, which we refuſe to others, that are voluntary or feeble. For 'tis evi⯑dent our pains and pleaſures, our paſſions and affections, which we never ſuppoſe to have any exiſtence beyond our perception, operate with greater violence, and are equally involuntary, as the impreſſions of figure and extenſion, colour and ſound, which we ſup⯑poſe to be permanent beings. The heat of [340] a fire, when moderate, is ſuppos'd to exiſt in the fire; but the pain, which it cauſes upon a near approach, is not taken to have any being except in the perception.

THESE vulgar opinions, then, being re⯑jected, we muſt ſearch for ſome other hy⯑potheſis, by which we may diſcover thoſe peculiar qualities in our impreſſions, which makes us attribute to them a diſtinct and continu'd exiſtence.

AFTER a little examination, we ſhall find, that all thoſe objects, to which we attribute a continu'd exiſtence, have a peculiar con⯑ſtancy, which diſtinguiſhes them from the impreſſions, whoſe exiſtence depends upon our perception. Thoſe mountains, and houſes, and trees, which lie at preſent under my eye, have always appear'd to me in the ſame order; and when I loſe ſight of them by ſhutting my eyes or turning my head, I ſoon after find them return upon me with⯑out the leaſt alteration. My bed and table, my books and papers, preſent themſelves in the ſame uniform manner, and change not upon account of any interruption in my ſeeing or perceiving them. This is the caſe with all the impreſſions, whoſe objects are ſuppos'd to have an external exiſtence; and is the caſe [341] with no other impreſſions, whether gentle or violent, voluntary or involuntary.

THIS conſtancy, however, is not ſo per⯑fect as not to admit of very conſiderable ex⯑ceptions. Bodies often change their poſi⯑tion and qualities, and after a little abſence or interruption may become hardly know⯑able. But here 'tis obſervable, that even in theſe changes they preſerve a coherence, and have a regular dependence on each other; which is the foundation of a kind of rea⯑ſoning from cauſation, and produces the opinion of their continu'd exiſtence. When I return to my chamber after an hour's ab⯑ſence, I find not my fire in the ſame ſitu⯑ation, in which I left it: But then I am accuſtom'd in other inſtances to ſee a like alteration produc'd in a like time, whether I am preſent or abſent, near or remote. This coherence, therefore, in their changes is one of the characteriſtics of external objects, as well as their conſtancy.

HAVING found that the opinion of the continu'd exiſtence of body depends on the COHERENCE and CONSTANCY of certain impreſſions, I now proceed to examine after what manner theſe qualities give riſe to ſo extraordinary an opinion. To begin with the coherence; we may obſerve, [342] that tho' thoſe internal impreſſions, which we regard as fleeting and periſhing, have alſo a certain coherence or regularity in their ap⯑pearances, yet 'tis of ſomewhat a different nature, from that which we diſcover in bo⯑dies. Our paſſions are found by experience to have a mutual connexion with and de⯑pendance on each other; but on no occa⯑ſion is it neceſſary to ſuppoſe, that they have exiſted and operated, when they were not perceiv'd, in order to preſerve the ſame dependance and connexion, of which we have had experience. The caſe is not the ſame with relation to external objects. Thoſe require a continu'd exiſtence, or otherwiſe loſe, in a great meaſure, the regularity of their operation. I am here ſeated in my chamber with my face to the fire; and all the objects, that ſtrike my ſenſes, are con⯑tain'd in a few yards around me. My me⯑mory, indeed, informs me of the exiſtence of many objects; but then this information extends not beyond their paſt exiſtence, nor do either my ſenſes or memory give any teſtimony to the continuance of their being. When therefore I am thus ſeated, and revolve over theſe thoughts, I hear on a ſudden a noiſe as of a door turning upon its hinges; and a little after ſee a porter, who [343] advances towards me. This gives occaſion to many new reflections and reaſonings. Firſt, I never have obſerv'd, that this noiſe cou'd proceed from any thing but the mo⯑tion of a door; and therefore conclude, that the preſent phaenomenon is a contradiction to all paſt experience, unleſs the door, which I remember on t'other ſide the cham⯑ber, be ſtill in being. Again, I have al⯑ways found, that a human body was poſſeſt of a quality, which I call gravity, and which hinders it from mounting in the air, as this porter muſt have done to arrive at my chamber, unleſs the ſtairs I remember be not annihilated by my abſence. But this is not all. I receive a letter, which upon open⯑ing I perceive by the hand-writing and ſub⯑ſcription to have come from a friend, who ſays he is two hundred leagues diſtant. 'Tis evident I can never account for this phae⯑nomenon, conformable to my experience in other inſtances, without ſpreading out in my mind the whole ſea and continent between us, and ſuppoſing the effects and continu'd exiſtence of poſts and ferries, according to my memory and obſervation. To conſider theſe phaenomena of the porter and letter in a certain light, they are contradictions to common experience, and may be regarded [344] as objections to thoſe maxims, which we form concerning the connexions of cauſes and effects. I am accuſtom'd to hear ſuch a ſound, and ſee ſuch an object in motion at the ſame time. I have not receiv'd in this particular inſtance both theſe perceptions. Theſe obſervations are contrary, unleſs I ſuppoſe that the door ſtill remains, and that it was open'd without my perceiving it: And this ſuppoſition, which was at firſt entirely arbitrary and hypothetical, acquires a force and evidence by its being the only one, upon which I can reconcile theſe contradictions. There is ſcarce a moment of my life, wherein there is not a ſimilar inſtance preſented to me, and I have not occaſion to ſuppoſe the continu'd exiſtence of objects, in order to connect their paſt and preſent appearances, and give them ſuch an union with each other, as I have found by experience to be ſuit⯑able to their particular natures and circum⯑ſtances. Here then I am naturally led to regard the world, as ſomething real and du⯑rable, and as preſerving its exiſtence, even when it is no longer preſent to my per⯑ception.

BUT tho' this concluſion from the cohe⯑rence of appearances may ſeem to be of the ſame nature with our reaſonings concern⯑ing [345] cauſes and effects; as being deriv'd from cuſtom, and regulated by paſt experience; we ſhall find upon examination, that they are at the bottom conſiderably different from each other, and that this inference ariſes from the underſtanding, and from cuſtom in an indirect and oblique manner. For 'twill readily be allow'd, that ſince nothing is ever really preſent to the mind, beſides its own perceptions, 'tis not only impoſſi⯑ble, that any habit ſhou'd ever be acquir'd otherwiſe than by the regular ſucceſſion of theſe perceptions, but alſo that any habit ſhou'd ever exceed that degree of regulari⯑ty. Any degree, therefore, of regularity in our perceptions, can never be a foundation for us to infer a greater degree of regulari⯑ty in ſome objects, which are not perceiv'd; ſince this ſuppoſes a contradiction, viz. a habit acquir'd by what was never preſent to the mind. But 'tis evident, that whenever we infer the continu'd exiſtence of the ob⯑jects of ſenſe from their coherence, and the frequency of their union, 'tis in order to beſtow on the objects a greater regularity than what is obſerv'd in our mere percep⯑tions. We remark a connexion betwixt two kinds of objects in their paſt appear⯑ance to the ſenſes, but are not able to ob⯑ſerve [346] this connexion to be perfectly con⯑ſtant, ſince the turning about of our head, or the ſhutting of our eyes is able to break it. What then do we ſuppoſe in this caſe, but that theſe objects ſtill continue their uſual connexion, notwithſtanding their apparent in⯑terruption, and that the irregular appearances are join'd by ſomething, of which we are inſenſible? But as all reaſoning concerning matters of fact ariſes only from cuſtom, and cuſtom can only be the effect of repeated perceptions, the extending of cuſtom and reaſoning beyond the perceptions can never be the direct and natural effect of the con⯑ſtant repetition and connexion, but muſt ariſe from the co-operation of ſome other principles.

I HAVE already ^* obſerv'd, in examining the foundation of mathematics, that the imagination, when ſet into any train of thinking, is apt to continue, even when its object fails it, and like a galley put in mo⯑tion by the oars, carries on its courſe with⯑out any new impulſe. This I have aſſign'd for the reaſon, why, after conſidering ſeve⯑ral looſe ſtandards of equality, and correct⯑ing them by each other, we proceed to ima⯑gine ſo correct and exact a ſtandard of that [347] relation, as is not liable to the leaſt error or variation. The ſame principle makes us eaſily entertain this opinion of the con⯑tinu'd exiſtence of body. Objects have a certain coherence even as they appear to our ſenſes; but this coherence is much greater and more uniform, if we ſuppoſe the objects to have a continu'd exiſtence; and as the mind is once in the train of ob⯑ſerving an uniformity among objects, it na⯑turally continues, till it renders the unifor⯑mity as compleat as poſſible. The ſimple ſuppoſition of their continu'd exiſtence ſuf⯑fices for this purpoſe, and gives us a notion of a much greater regularity among objects, than what they have when we look no far⯑ther than our ſenſes.

BUT whatever force we may aſcribe to this principle, I am afraid 'tis too weak to ſupport alone ſo vaſt an edifice, as is that of the continu'd exiſtence of all external bodies; and that we muſt join the conſtancy of their appearance to the coherence, in or⯑der to give a ſatisfactory account of that o⯑pinion. As the explication of this will lead me into a conſiderable compaſs of very pro⯑found reaſoning; I think it proper, in order to avoid confuſion, to give a ſhort ſketch or abridgment of my ſyſtem, and after⯑wards [348] draw out all its parts in their full compaſs. This inference from the conſtan⯑cy of our perceptions, like the precedent from their coherence, gives riſe to the opi⯑nion of the continu'd exiſtence of body, which is prior to that of its diſtinct exiſt⯑ence, and produces that latter principle.

WHEN we have been accuſtom'd to ob⯑ſerve a conſtancy in certain impreſſions, and have found, that the perception of the ſun or ocean, for inſtance, returns upon us af⯑ter an abſence or annihilation with like parts and in a like order, as at its firſt appearance, we are not apt to regard theſe interrupted per⯑ceptions as different, (which they really are) but on the contrary conſider them as indivi⯑dually the ſame, upon account of their re⯑ſemblance. But as this interruption of their exiſtence is contrary to their perfect identi⯑ty, and makes us regard the firſt impreſſion as annihilated, and the ſecond as newly created, we find ourſelves ſomewhat at a loſs, and are involv'd in a kind of contradiction. In order to free ourſelves from this difficul⯑ty, we diſguiſe, as much as poſſible, the interruption, or rather remove it entirely, by ſuppoſing that theſe interrupted percep⯑tions are connected by a real exiſtence, of which we are inſenſible. This ſuppoſition, [349] or idea of continu'd exiſtence, acquires a force and vivacity from the memory of theſe broken impreſſions, and from that propen⯑ſity, which they give us, to ſuppoſe them the ſame; and according to the precedent reaſoning, the very eſſence of belief conſiſts in the force and vivacity of the conception.

IN order to juſtify this ſyſtem, there are four things requiſite. Firſt, To explain the principium individuationis, or principle of identity. Secondly, Give a reaſon, why the reſemblance of our broken and interrupted perceptions induces us to attribute an identity to them. Thirdly, Account for that propen⯑ſity, which this illuſion gives, to unite theſe broken appearances by a continu'd exiſtence. Fourthly and laſtly, Explain that force and vivacity of conception, which ariſes from the propenſity.

FIRST, As to the principle of individua⯑tion; we may obſerve, that the view of any one object is not ſufficient to convey the idea of identity. For in that propoſition, an object is the ſame with itſelf, if the idea expreſs'd by the word, object, were no ways diſtinguiſh'd from that meant by itſelf; we really ſhou'd mean nothing, nor wou'd the propoſition contain a predicate and a ſub⯑ject, which however are imply'd in this [350] affirmation. One ſingle object conveys the idea of unity, not that of identity.

ON the other hand, a multiplicity of ob⯑jects can never convey this idea, however re⯑ſembling they may be ſuppos'd. The mind always pronounces the one not to be the o⯑ther, and conſiders them as forming two, three, or any determinate number of objects, whoſe exiſtences are entirely diſtinct and independent.

SINCE then both number and unity are incompatible with the relation of identity, it muſt lie in ſomething that is neither of them. But to tell the truth, at firſt ſight this ſeems utterly impoſſible. Betwixt uni⯑ty and number there can be no medium; no more than betwixt exiſtence and non⯑exiſtence. After one object is ſuppos'd to exiſt, we muſt either ſuppoſe another alſo to exiſt; in which caſe we have the idea of number: Or we muſt ſuppoſe it not to exiſt; in which caſe the firſt object remains at unity.

TO remove this difficulty, let us have recourſe to the idea of time or duration. I have already obſerv'd,^* that time, in a ſtrict ſenſe, implies ſucceſſion, and that when we apply its idea to any unchangeable object, [351] 'tis only by a fiction of the imagination, by which the unchangeable object is ſuppos'd to participate of the changes of the co-ex⯑iſtent objects, and in particular of that of our perceptions. This fiction of the imagination almoſt univerſally takes place; and 'tis by means of it, that a ſingle object, plac'd be⯑fore us, and ſurvey'd for any time without our diſcovering in it any interruption or va⯑riation, is able to give us a notion of iden⯑tity. For when we conſider any two points of this time, we may place them in diffe⯑rent lights: We may either ſurvey them at the very ſame inſtant; in which caſe they give us the idea of number, both by them⯑ſelves and by the object; which muſt be multiply'd, in order to be conceiv'd at once, as exiſtent in theſe two different points of time: Or on the other hand, we may trace the ſucceſſion of time by a like ſucceſſion of ideas, and conceiving firſt one moment, along with the object then exiſtent, imagine afterwards a change in the time without any variation or interruption in the object; in which caſe it gives us the idea of unity. Here then is an idea, which is a medium betwixt unity and number; or more pro⯑perly ſpeaking, is either of them, according to the view, in which we take it: And this [352] idea we call that of identity. We cannot, in any propriety of ſpeech, ſay, that an object is the ſame with itſelf, unleſs we mean, that the object exiſtent at one time is the ſame with itſelf exiſtent at another. By this means we make a difference, be⯑twixt the idea meant by the word, object, and that meant by itſelf, without going the length of number, and at the ſame time without reſtraining ourſelves to a ſtrict and abſolute unity.

THUS the principle of individuation is nothing but the invariableneſs and uninter⯑ruptedneſs of any object, thro' a ſuppos'd vari⯑ation of time, by which the mind can trace it in the different periods of its exiſtence, without any break of the view, and without being oblig'd to form the idea of multipli⯑city or number.

I NOW proceed to explain the ſecond part of my ſyſtem, and ſhew why the con⯑ſtancy of our perceptions makes us aſcribe to them a perfect numerical identity, tho' there be very long intervals betwixt their ap⯑pearance, and they have only one of the eſſential qualities of identity, viz. invari⯑ableneſs. That I may avoid all ambiguity and confuſion on this head, I ſhall obſerve, that I here account for the opinions and be⯑lief [353] of the vulgar with regard to the exiſ⯑tence of body; and therefore muſt entirely conform myſelf to their manner of thinking and of expreſſing themſelves. Now we have already obſerv'd, that however philoſophers may diſtinguiſh betwixt the objects and per⯑ceptions of the ſenſes; which they ſuppoſe co-exiſtent and reſembling; yet this is a diſ⯑tinction, which is not comprehended by the generality of mankind, who as they perceive only one being, can never aſſent to the opi⯑nion of a double exiſtence and repreſenta⯑tion. Thoſe very ſenſations, which enter by the eye or ear, are with them the true objects, nor can they readily conceive that this pen or paper, which is immediately perceiv'd, repreſents another, which is dif⯑ferent from, but reſembling it. In order, therefore, to accommodate myſelf to their notions, I ſhall at firſt ſuppoſe; that there is only a ſingle exiſtence, which I ſhall call indifferently object or perception, according as it ſhall ſeem beſt to ſuit my purpoſe, un⯑derſtanding by both of them what any com⯑mon man means by a hat, or ſhoe, or ſtone, or any other impreſſion, convey'd to him by his ſenſes. I ſhall be ſure to give warn⯑ing, when I return to a more philoſophical way of ſpeaking and thinking.

[354] TO enter, therefore, upon the queſtion concerning the ſource of the error and de⯑ception with regard to identity, when we attribute it to our reſembling perceptions, notwithſtanding their interruption; I muſt here recal an obſervation, which I have al⯑ready prov'd and explain'd ^*. Nothing is more apt to make us miſtake one idea for another, than any relation betwixt them, which aſſociates them together in the ima⯑gination, and makes it paſs with facility from one to the other. Of all relations, that of reſemblance is in this reſpect the moſt effi⯑cacious; and that becauſe it not only cauſes an aſſociation of ideas, but alſo of diſpoſi⯑tions, and makes us conceive the one idea by an act or operation of the mind, ſimilar to that by which we conceive the other. This circumſtance I have obſerv'd to be of great moment; and we may eſtabliſh it for a general rule, that whatever ideas place the mind in the ſame diſpoſition or in ſimilar ones, are very apt to be confounded. The mind readily paſſes from one to the other, and perceives not the change without a ſtrict attention, of which, generally ſpeaking, 'tis wholly incapable.

[355] IN order to apply this general maxim, we muſt firſt examine the diſpoſition of the mind in viewing any object which preſerves a perfect identity, and then find ſome other object, that is confounded with it, by cauſ⯑ing a ſimilar diſpoſition. When we fix our thought on any object, and ſuppoſe it to continue the ſame for ſome time; 'tis evi⯑dent we ſuppoſe the change to lie only in the time, and never exert ourſelves to pro⯑duce any new image or idea of the object. The faculties of the mind repoſe themſelves in a manner, and take no more exerciſe, than what is neceſſary to continue that idea, of which we were formerly poſſeſt, and which ſubſiſts without variation or interruption. The paſſage from one moment to another is ſcarce felt, and diſtinguiſhes not itſelf by a different perception or idea, which may re⯑quire a different direction of the ſpirits, in order to its conception.

NOW what other objects, beſide identical ones, are capable of placing the mind in the ſame diſpoſition, when it conſiders them, and of cauſing the ſame uninterrupted paſ⯑ſage of the imagination from one idea to another? This queſtion is of the laſt im⯑portance. For if we can find any ſuch ob⯑jects, we may certainly conclude, from the [356] foregoing principle, that they are very na⯑turally confounded with identical ones, and are taken for them in moſt of our rea⯑ſonings. But tho' this queſtion be very im⯑portant, 'tis not very difficult nor doubtful. For I immediately reply, that a ſucceſſion of related objects places the mind in this diſpoſition, and is conſider'd with the ſame ſmooth and uninterrupted progreſs of the imagination, as attends the view of the ſame invariable object. The very nature and eſ⯑ſence of relation is to connect our ideas with each other, and upon the appearance of one, to facilitate the tranſition to its cor⯑relative. The paſſage betwixt related ideas is, therefore, ſo ſmooth and eaſy, that it produces little alteration on the mind, and ſeems like the continuation of the ſame ac⯑tion; and as the continuation of the ſame action is an effect of the continu'd view of the ſame object, 'tis for this reaſon we at⯑tribute ſameneſs to every ſucceſſion of re⯑lated objects. The thought ſlides along the ſucceſſion with equal facility, as if it con⯑ſider'd only one object; and therefore con⯑founds the ſucceſſion with the identity.

WE ſhall afterwards ſee many inſtances of this tendency of relation to make us aſcribe an identity to different objects; but ſhall here [357] confine ourſelves to the preſent ſubject. We find by experience, that there is ſuch a con⯑ſtancy in almoſt all the impreſſions of the ſenſes, that their interruption produces no alteration on them, and hinders them not from returning the ſame in appearance and in ſituation as at their firſt exiſtence. I ſurvey the furniture of my chamber; I ſhut my eyes, and afterwards open them; and find the new perceptions to reſemble per⯑fectly thoſe, which formerly ſtruck my ſen⯑ſes. This reſemblance is obſerv'd in a thou⯑ſand inſtances, and naturally connects to⯑gether our ideas of theſe interrupted per⯑ceptions by the ſtrongeſt relation, and con⯑veys the mind with an eaſy tranſition from one to another. An eaſy tranſition or paſ⯑ſage of the imagination, along the ideas of theſe different and interrupted perceptions, is almoſt the ſame diſpoſition of mind with that in which we conſider one conſtant and uninterrupted perception. 'Tis therefore very natural for us to miſtake the one for the other ^*.

[358] THE perſons, who entertain this opinion concerning the identity of our reſembling perceptions, are in general all the unthinking and unphiloſophical part of mankind, (that is, all of us, at one time or other) and conſe⯑quently ſuch as ſuppoſe their perceptions to be their only objects, and never think of a double exiſtence internal and external, re⯑preſenting and repreſented. The very image, which is preſent to the ſenſes, is with us the real body; and 'tis to theſe interrupted images we aſcribe a perfect identity. But as the interruption of the appearance ſeems contrary to the identity, and naturally leads us to regard theſe reſembling perceptions as different from each other, we here find our⯑ſelves at a loſs how to reconcile ſuch oppo⯑ſite opinions. The ſmooth paſſage of the imagination along the ideas of the reſem⯑bling perceptions makes us aſcribe to them a perfect identity. The interrupted manner [359] of their appearance makes us conſider them as ſo many reſembling, but ſtill diſtinct be⯑ings, which appear after certain intervals. The perplexity ariſing from this contradic⯑tion produces a propenſion to unite theſe broken appearances by the fiction of a con⯑tinu'd exiſtence, which is the third part of that hypotheſis I propos'd to explain.

NOTHING is more certain from expe⯑rience, than that any contradiction either to the ſentiments or paſſions gives a ſenſible un⯑eaſineſs, whether it proceeds from without or from within; from the oppoſition of ex⯑ternal objects, or from the combat of in⯑ternal principles. On the contrary, what⯑ever ſtrikes in with the natural propenſities, and either externally forwards their ſatiſ⯑faction, or internally concurs with their movements, is ſure to give a ſenſible plea⯑ſure. Now there being here an oppoſition betwixt the notion of the identity of re⯑ſembling perceptions, and the interruption of their appearance, the mind muſt be un⯑eaſy in that ſituation, and will naturally ſeek relief from the uneaſineſs. Since the un⯑eaſineſs ariſes from the oppoſition of two contrary principles, it muſt look for relief by ſacrificing the one to the other. But as the ſmooth paſſage of our thought along [360] our reſembling perceptions makes us a⯑ſcribe to them an identity, we can never without reluctance yield up that opinion. We muſt, therefore, turn to the other ſide, and ſuppoſe that our perceptions are no longer interrupted, but preſerve a continu'd as well as an invariable exiſtence, and are by that means entirely the ſame. But here the in⯑terruptions in the appearance of theſe per⯑ceptions are ſo long and frequent, that 'tis impoſſible to overlook them; and as the appearance of a perception in the mind and its exiſtence ſeem at firſt ſight entirely the ſame, it may be doubted, whether we can ever aſſent to ſo palpable a contradiction, and ſuppoſe a perception to exiſt without being preſent to the mind. In order to clear up this matter, and learn how the in⯑terruption in the appearance of a perception implies not neceſſarily an interruption in its exiſtence, 'twill be proper to touch upon ſome principles, which we ſhall have occa⯑ſion to explain more fully afterwards ^*.

WE may begin with obſerving, that the difficulty in the preſent caſe is not concern⯑ing the matter of fact, or whether the mind forms ſuch a concluſion concerning the continu'd exiſtence of its perceptions, but [361] only concerning the manner in which the concluſion is form'd, and principles from which it is deriv'd. 'Tis certain, that al⯑moſt all mankind, and even philoſophers themſelves, for the greateſt part of their lives, take their perceptions to be their only objects, and ſuppoſe, that the very being, which is intimately preſent to the mind, is the real body or material exiſtence. 'Tis alſo certain, that this very perception or ob⯑ject is ſuppos'd to have a continu'd unin⯑terrupted being, and neither to be annihi⯑lated by our abſence, nor to be brought in⯑to exiſtence by our preſence. When we are abſent from it, we ſay it ſtill exiſts, but that we do not feel, we do not ſee it. When we are preſent, we ſay we feel, or ſee it. Here then may ariſe two queſtions; Firſt, How we can ſatisfy ourſelves in ſup⯑poſing a perception to be abſent from the mind without being annihilated. Secondly, After what manner we conceive an object to become preſent to the mind, without ſome new creation of a perception or image; and what we mean by this ſeeing, and feeling, and perceiving.

As to the firſt queſtion; we may ob⯑ſerve, that what we call a mind, is nothing but a heap or collection of different percep⯑tions, [362] united together by certain relations, and ſuppos'd, tho' falſely, to be endow'd with a perfect ſimplicity and identity. Now as every perception is diſtinguiſhable from an⯑other, and may be conſider'd as ſeparately exiſtent; it evidently follows, that there is no abſurdity in ſeparating any particular per⯑ception from the mind; that is, in breaking off all its relations, with that connected maſs of perceptions, which conſtitute a thinking being.

THE ſame reaſoning affords us an an⯑ſwer to the ſecond queſtion. If the name of perception renders not this ſeparation from a mind abſurd and contradictory, the name of object, ſtanding for the very ſame thing, can never render their conjunction impoſſible. External objects are ſeen, and felt, and become preſent to the mind; that is, they acquire ſuch a relation to a con⯑nected heap of perceptions, as to influence them very conſiderably in augmenting their number by preſent reflections and paſſions, and in ſtoring the memory with ideas. The ſame continu'd and uninterrupted Being may, therefore, be ſometimes preſent to the mind, and ſometimes abſent from it, without any real or eſſential change in the Being itſelf. An interrupted appearance to the ſenſes im⯑plies [363] not neceſſarily an interruption in the exiſtence. The ſuppoſition of the continu'd exiſtence of ſenſible objects or perceptions involves no contradiction. We may eaſily indulge our inclination to that ſuppoſition. When the exact reſemblance of our percep⯑tions makes us aſcribe to them an identity, we may remove the ſeeming interruption by feigning a continu'd being, which may fill thoſe intervals, and preſerve a perfect and entire identity to our perceptions.

BUT as we here not only feign but be⯑lieve this continu'd exiſtence, the queſtion is, from whence ariſes ſuch a belief; and this queſtion leads us to the fourth member of this ſyſtem. It has been prov'd already, that belief in general conſiſts in nothing, but the vivacity of an idea; and that an idea may acquire this vivacity by its relation to ſome preſent impreſſion. Impreſſions are naturally the moſt vivid perceptions of the mind; and this quality is in part convey'd by the rela⯑tion to every connected idea. The relation cauſes a ſmooth paſſage from the impreſ⯑ſion to the idea, and even gives a propen⯑ſity to that paſſage. The mind falls ſo eaſi⯑ly from the one perception to the other, that it ſcarce perceives the change, but retains in the ſecond a conſiderable ſhare of the viva⯑city [364] of the firſt. It is excited by the live⯑ly impreſſion; and this vivacity is convey'd to the related idea, without any great di⯑minution in the paſſage, by reaſon of the ſmooth tranſition and the propenſity of the imagination.

BUT ſuppoſe, that this propenſity ariſes from ſome other principle, beſides that of relation; 'tis evident it muſt ſtill have the ſame effect, and convey the vivacity from the impreſſion to the idea. Now this is ex⯑actly the preſent caſe. Our memory pre⯑ſents us with a vaſt number of inſtances of perceptions perfectly reſembling each o⯑ther, that return at different diſtances of time, and after conſiderable interruptions. This reſemblance gives us a propenſion to conſider theſe interrupted perceptions as the ſame; and alſo a propenſion to connect them by a continu'd exiſtence, in order to juſtify this identity, and avoid the contradiction, in which the interrupted appearance of theſe perceptions ſeems neceſſarily to involve us. Here then we have a propenſity to feign the continu'd exiſtence of all ſenſible ob⯑jects; and as this propenſity ariſes from ſome lively impreſſions of the memory, it beſtows a vivacity on that fiction; or in other words, makes us believe the continu'd exiſtence of [365] body. If ſometimes we aſcribe a continu'd exiſtence to objects, which are perfectly new to us, and of whoſe conſtancy and coherence we have no experience, 'tis becauſe the man⯑ner, in which they preſent themſelves to our ſenſes, reſembles that of conſtant and coherent objects; and this reſemblance is a ſource of reaſoning and analogy, and leads us to attribute the ſame qualities to the ſimilar objects.

I BELIEVE an intelligent reader will find leſs difficulty to aſſent to this ſyſtem, than to comprehend it fully and diſtinctly, and will allow, after a little reflection, that every part carries its own proof along with it. 'Tis indeed evident, that as the vulgar ſuppoſe their perceptions to be their only ob⯑jects, and at the ſame time believe the con⯑tinu'd exiſtence of matter, we muſt account for the origin of the belief upon that ſup⯑poſition. Now upon that ſuppoſition, 'tis a falſe opinion that any of our objects, or perceptions, are identically the ſame after an interruption; and conſequently the opinion of their identity can never ariſe from reaſon, but muſt ariſe from the imagination. The imagination is ſeduc'd into ſuch an opinion only by means of the reſemblance of certain perceptions; ſince we find they are only our [366] reſembling perceptions, which we have a propenſion to ſuppoſe the ſame. This pro⯑penſion to beſtow an identity on our re⯑ſembling perceptions, produces the fiction of a continu'd exiſtence; ſince that fiction, as well as the identity, is really falſe, as is ac⯑knowledg'd by all philoſophers, and has no other effect than to remedy the interruption of our perceptions, which is the only cir⯑cumſtance that is contrary to their identity. In the laſt place this propenſion cauſes be⯑lief by means of the preſent impreſſions of the memory; ſince without the remembrance of former ſenſations, 'tis plain we never ſhou'd have any belief of the continu'd ex⯑iſtence of body. Thus in examining all theſe parts, we find that each of them is ſupported by the ſtrongeſt proofs; and that all of them together form a conſiſtent ſyſtem, which is perfectly convincing. A ſtrong propenſity or inclination alone, without any preſent impreſſion, will ſometimes cauſe a belief or opinion. How much more when aided by that circumſtance?

BUT tho' we are led after this manner, by the natural propenſity of the imagination, to aſcribe a continu'd exiſtence to thoſe ſen⯑ſible objects or perceptions, which we find to reſemble each other in their interrupted [367] appearance; yet a very little reflection and philoſophy is ſufficient to make us perceive the fallacy of that opinion. I have already obſerv'd, that there is an intimate connexion betwixt thoſe two principles, of a continu'd and of a diſtinct or independent exiſtence, and that we no ſooner eſtabliſh the one than the other follows, as a neceſſary conſequence. 'Tis the opinion of a continu'd exiſtence, which firſt takes place, and without much ſtudy or reflection draws the other along with it, wherever the mind follows its firſt and moſt natural tendency. But when we compare experiments, and reaſon a little upon them, we quickly perceive, that the doctrine of the independent exiſtence of our ſenſible perceptions is contrary to the plaineſt experience. This leads us backward upon our footſteps to perceive our error in attributing a continu'd exiſtence to our per⯑ceptions, and is the origin of many very curious opinions, which we ſhall here en⯑deavour to account for.

'TWILL firſt be proper to obſerve a few of thoſe experiments, which convince us, that our perceptions are not poſſeſt of any independent exiſtence. When we preſs one eye with a finger, we immediately perceive all the objects to become double, [368] and one half of them to be remov'd from their common and natural poſition. But as we do not attribute a continu'd exiſtence to both theſe perceptions, and as they are both of the ſame nature, we clearly per⯑ceive, that all our perceptions are dependent on our organs, and the diſpoſition of our nerves and animal ſpirits. This opinion is confirm'd by the ſeeming encreaſe and diminution of objects, according to their diſtance; by the apparent alterations in their figure; by the changes in their colour and other qualities from our ſickneſs and diſ⯑tempers; and by an infinite number of o⯑ther experiments of the ſame kind; from all which we learn, that our ſenſible per⯑ceptions are not poſſeſt of any diſtinct or independent exiſtence.

THE natural conſequence of this rea⯑ſoning ſhou'd be, that our perceptions have no more a continu'd than an independent exiſtence; and indeed philoſophers have ſo far run into this opinion, that they change their ſyſtem, and diſtinguiſh, (as we ſhall do for the future) betwixt perceptions and objects, of which the former are ſuppos'd to be interrupted, and periſhing, and different at every different return; the latter to be uninterrupted, and to preſerve a continu'd [369] exiſtence and identity. But however phi⯑loſophical this new ſyſtem may be eſteem'd, I aſſert that 'tis only a palliative remedy, and that it contains all the difficulties of the vulgar ſyſtem, with ſome others, that are peculiar to itſelf. There are no princi⯑ples either of the underſtanding or fan⯑cy, which lead us directly to embrace this opinion of the double exiſtence of per⯑ceptions and objects, nor can we arrive at it but by paſſing thro' the common hypo⯑theſis of the identity and continuance of our interrupted perceptions. Were we not firſt perſwaded, that our perceptions are our only objects, and continue to exiſt even when they no longer make their appearance to the ſenſes, we ſhou'd never be led to think, that our perceptions and objects are different, and that our objects alone preſerve a continu'd exiſtence. ‘The latter hypotheſis has no primary recommendation either to reaſon or the imagination, but acquires all its influence on the imagination from the former.’ This propoſition contains two parts, which we ſhall endeavour to prove as diſtinctly and clearly, as ſuch abſtruſe ſubjects will permit.

As to the firſt part of the propoſition, that this philoſophical hypotheſis has no pri⯑mary [370] recommendation, either to reaſon or the imagination, we may ſoon ſatisfy ourſelves with regard to reaſon by the following reflections. The only exiſtences, of which we are certain, are perceptions, which being immediately preſent to us by conſciouſneſs, command our ſtrongeſt aſſent, and are the firſt foundation of all our concluſions. The only concluſion we can draw from the ex⯑iſtence of one thing to that of another, is by means of the relation of cauſe and effect, which ſhews, that there is a connexion be⯑twixt them, and that the exiſtence of one is dependent on that of the other. The idea of this relation is deriv'd from paſt ex⯑perience, by which we find, that two beings are conſtantly conjoin'd together, and are always preſent at once to the mind. But as no beings are ever preſent to the mind but perceptions; it follows that we may ob⯑ſerve a conjunction or a relation of cauſe and effect between different perceptions, but can never obſerve it between percep⯑tions and objects. 'Tis impoſſible, there⯑fore, that from the exiſtence or any of the qualities of the former, we can ever form any concluſion concerning the exiſtence of the latter, or ever ſatisfy our reaſon in this particular.

[371] 'TIS no leſs certain, that this philoſophi⯑cal ſyſtem has no primary recommendation to the imagination, and that that faculty wou'd never, of itſelf, and by its original tendency, have fallen upon ſuch a principle. I confeſs it will be ſomewhat difficult to prove this to the full ſatisfaction of the reader; becauſe it implies a negative, which in many caſes will not admit of any poſitive proof. If any one wou'd take the pains to examine this queſtion, and wou'd invent a ſyſtem, to account for the direct origin of this opi⯑nion from the imagination, we ſhou'd be able, by the examination of that ſyſtem, to pronounce a certain judgment in the preſent ſubject. Let it be taken for granted, that our perceptions are broken, and interrupted, and however like, are ſtill different from each other; and let any one upon this ſup⯑poſition ſhew why the fancy, directly and immediately, proceeds to the belief of an⯑other exiſtence, reſembling theſe perceptions in their nature, but yet continu'd, and un⯑interrupted, and identical; and after he has done this to my ſatisfaction, I promiſe to renounce my preſent opinion. Mean while I cannot forbear concluding, from the very abſtractedneſs and difficulty of the firſt ſup⯑poſition, that 'tis an improper ſubject for [372] the fancy to work upon. Whoever wou'd explain the origin of the common opinion concerning the continu'd and diſtinct exiſ⯑tence of body, muſt take the mind in its common ſituation, and muſt proceed upon the ſuppoſition, that our perceptions are our only objects, and continue to exiſt even when they are not perceiv'd. Tho' this opinion be falſe, 'tis the moſt natural of any, and has alone any primary recommendation to the fancy.

AS to the ſecond part of the propoſition, that the philoſophical ſyſtem acquires all its influence on the imagination from the vulgar one; we may obſerve, that this is a na⯑tural and unavoidable conſequence of the foregoing concluſion, that it has no primary recommendation to reaſon or the imagination. For as the philoſophical ſyſtem is found by experience to take hold of many minds, and in particular of all thoſe, who reflect ever ſo little on this ſubject, it muſt derive all its authority from the vulgar ſyſtem; ſince it has no original authority of its own. The manner, in which theſe two ſyſtems, tho' directly contrary, are connected together, may be explain'd, as follows.

THE imagination naturally runs on in this train of thinking. Our perceptions are [373] our only objects: Reſembling perceptions are the ſame, however broken or uninterrupted in their appearance: This appearing inter⯑ruption is contrary to the identity: The interruption conſequently extends not be⯑yond the appearance, and the perception or object really continues to exiſt, even when abſent from us: Our ſenſible perceptions have, therefore, a continu'd and uninterrupted exiſtence. But as a little reflection deſtroys this concluſion, that our perceptions have a continu'd exiſtence, by ſhewing that they have a dependent one, 'twou'd naturally be expected, that we muſt altogether reject the opinion, that there is ſuch a thing in nature as a continu'd exiſtence, which is preſerv'd even when it no longer appears to the ſenſes. The caſe, however, is otherwiſe. Philoſo⯑phers are ſo far from rejecting the opinion of a continu'd exiſtence upon rejecting that of the independence and continuance of our ſenſible perceptions, that tho' all ſects agree in the latter ſentiment, the former, which is, in a manner, its neceſſary conſequence, has been peculiar to a few extravagant ſcep⯑tics; who after all maintain'd that opinion in words only, and were never able to bring themſelves ſincerely to believe it.

[374] THERE is a great difference betwixt ſuch opinions as we form after a calm and pro⯑found reflection, and ſuch as we embrace by a kind of inſtinct or natural impulſe, on account of their ſuitableneſs and conformity to the mind. If theſe opinions become con⯑trary, 'tis not difficult to foreſee which of them will have the advantage. As long as our attention is bent upon the ſubject, the philoſophical and ſtudy'd principle may pre⯑vail; but the moment we relax our thoughts, nature will diſplay herſelf, and draw us back to our former opinion. Nay ſhe has ſome⯑times ſuch an influence, that ſhe can ſtop our progreſs, even in the midſt of our moſt pro⯑found reflections, and keep us from run⯑ning on with all the conſequences of any philoſophical opinion. Thus tho' we clear⯑ly perceive the dependence and interruption of our perceptions, we ſtop ſhort in our car⯑reer, and never upon that account reject the notion of an independent and continu'd exiſtence. That opinion has taken ſuch deep root in the imagination, that 'tis impoſſible ever to eradicate it, nor will any ſtrain'd metaphyſical conviction of the dependence of our perceptions be ſufficient for that pur⯑poſe.

[375] BUT tho' our natural and obvious prin⯑ciples here prevail above our ſtudy'd reflec⯑tions, 'tis certain there muſt be ſome ſtruggle and oppoſition in the caſe; at leaſt ſo long as theſe reflections retain any force or vi⯑vacity. In order to ſet ourſelves at eaſe in this particular, we contrive a new hypotheſis, which ſeems to comprehend both theſe prin⯑ciples of reaſon and imagination. This hy⯑potheſis is the philoſophical one of the double exiſtence of perceptions and objects; which pleaſes our reaſon, in allowing, that our de⯑pendent perceptions are interrupted and dif⯑ferent; and at the ſame time is agreeable to the imagination, in attributing a continu'd exiſtence to ſomething elſe, which we call objects. This philoſophical ſyſtem, therefore, is the monſtrous offspring of two principles, which are contrary to each other, which are both at once embrac'd by the mind, and which are unable mutually to deſtroy each other. The imagination tells us, that our reſembling perceptions have a continu'd and uninterrupted exiſtence, and are not an⯑nihilated by their abſence. Reflection tells us, that even our reſembling perceptions are interrupted in their exiſtence, and different from each other. The contradiction betwixt theſe opinions we elude by a new fiction, [376] which is conformable to the hypotheſes both of reflection and fancy, by aſcribing theſe contrary qualities to different exiſtences; the interruption to perceptions, and the continu⯑ance to objects. Nature is obſtinate, and will not quit the field, however ſtrongly attack'd by reaſon; and at the ſame time reaſon is ſo clear in the point, that there is no poſſi⯑bility of diſguiſing her. Not being able to reconcile theſe two enemies, we endea⯑vour to ſet ourſelves at eaſe as much as poſ⯑ſible, by ſucceſſively granting to each what⯑ever it demands, and by feigning a double exiſtence, where each may find ſomething, that has all the conditions it deſires. Were we fully convinc'd, that our reſembling per⯑ceptions are continu'd, and identical, and in⯑dependent, we ſhou'd never run into this opinion of a double exiſtence; ſince we ſhou'd find ſatisfaction in our firſt ſuppoſition, and wou'd not look beyond. Again, were we fully convinc'd, that our perceptions are de⯑pendent, and interrupted, and different, we ſhou'd be as little inclin'd to embrace the opinion of a double exiſtence; ſince in that caſe we ſhou'd clearly perceive the error of our firſt ſuppoſition of a continu'd exiſtence, and wou'd never regard it any farther. 'Tis therefore from the intermediate ſituation of [377] the mind, that this opinion ariſes, and from ſuch an adherence to theſe two contrary principles, as makes us ſeek ſome pretext to juſtify our receiving both; which happi⯑ly at laſt is found in the ſyſtem of a double exiſtence.

ANOTHER advantage of this philoſophi⯑cal ſyſtem is its ſimilarity to the vulgar one; by which means we can humour our rea⯑ſon for a moment, when it becomes trou⯑bleſome and ſollicitous; and yet upon its leaſt negligence or inattention, can eaſily return to our vulgar and natural notions. Accordingly we find, that philoſophers neg⯑lect not this advantage; but immediately upon leaving their cloſets, mingle with the reſt of manking in thoſe exploded opinions, that our perceptions are our only objects, and continue identically and uninterrupted⯑ly the ſame in all their interrupted appear⯑ances.

THERE are other particulars of this ſyſtem, wherein we may remark its depen⯑dence on the fancy, in a very conſpicuous manner. Of theſe, I ſhall obſerve the two following. Firſt, We ſuppoſe external ob⯑jects to reſemble internal perceptions. I have already ſhewn, that the relation of cauſe and effect can never afford us any [378] juſt concluſion from the exiſtence or quali⯑ties of our perceptions to the exiſtence of external continu'd objects: And I ſhall far⯑ther add, that even tho' they cou'd afford ſuch a concluſion, we ſhou'd never have any reaſon to infer, that our objects reſem⯑ble our perceptions. That opinion, there⯑fore, is deriv'd from nothing but the qua⯑lity of the fancy above-explain'd, that it borrows all its ideas from ſome preccdent per⯑ception. We never can conceive any thing but perceptions, and therefore muſt make every thing reſemble them.

SECONDLY, As we ſuppoſe our objects in general to reſemble our perceptions, ſo we take it for granted, that every particular ob⯑ject reſembles that perception, which it cauſes. The relation of cauſe and effect determines us to join the other of reſemblance; and the ideas of theſe exiſtences being already united together in the fancy by the former relation, we naturally add the latter to com⯑pleat the union. We have a ſtrong pro⯑penſity to compleat every union by joining new relations to thoſe which we have be⯑fore obſerv'd betwixt any ideas, as we ſhall have occaſion to obſerve preſently ^*.

[379] HAVING thus given an account of all the ſyſtems both popular and philoſophical, with regard to external exiſtences, I cannot forbear giving vent to a certain ſentiment, which ariſes upon reviewing thoſe ſyſtems. I begun this ſubject with premiſing, that we ought to have an implicit faith in our ſenſes, and that this wou'd be the conlu⯑ſion, I ſhou'd draw from the whole of my reaſoning. But to be ingenuous, I feel my⯑ſelf at preſent of a quite contrary ſentiment, and am more inclin'd to repoſe no faith at all in my ſenſes, or rather imagination, than to place in it ſuch an implicit confidence. I cannot conceive how ſuch trivial qualities of the fancy, conducted by ſuch falſe ſup⯑poſitions, can ever lead to any ſolid and rational ſyſtem. They are the coherence and conſtancy of our perceptions, which produce the opinion of their continu'd exiſ⯑tence; tho' theſe qualities of perceptions have no perceivable connexion with ſuch an exiſtence. The conſtancy of our per⯑ceptions has the moſt conſiderable effect, and yet is attended with the greateſt diffi⯑culties. 'Tis a groſs illuſion to ſuppoſe, that our reſembling perceptions are nume⯑rically the ſame; and 'tis this illuſion, which leads us into the opinion, that theſe per⯑ceptions [380] are uninterrupted, and are ſtill ex⯑iſtent, even when they are not preſent to the ſenſes. This is the caſe with our po⯑pular ſyſtem. And as to our philoſophical one, 'tis liable to the ſame difficulties; and is over-and-above loaded with this abſurdi⯑ty, that it at once denies and eſtabliſhes the vulgar ſuppoſition. Philoſophers deny our reſembling perceptions to be identically the ſame, and uninterrupted; and yet have ſo great a propenſity to believe them ſuch, that they arbitrarily invent a new ſet of percep⯑tions, to which they attribute theſe quali⯑ties. I ſay, a new ſet of perceptions: For we may well ſuppoſe in general, but 'tis im⯑poſſible for us diſtinctly to conceive, objects to be in their nature any thing but exactly the ſame with perceptions. What then can we look for from this confuſion of ground⯑leſs and extraordinary opinions but error and falſhood? And how can we juſtify to ourſelves any belief we repoſe in them?

THIS ſceptical doubt, both with reſpect to reaſon and the ſenſes, is a malady, which can never be radically cur'd, but muſt re⯑turn upon us every moment, however we may chace it away, and ſometimes may ſeem entirely free from it. 'Tis impoſſible upon any ſyſtem to defend either our un⯑derſtanding [381] or ſenſes; and we but expoſe them farther when we endeavour to juſtify them in that manner. As the ſceptical doubt ariſes naturally from a profound and intenſe reflection on thoſe ſubjects, it al⯑ways encreaſes, the farther we carry our re⯑flections, whether in oppoſition or confor⯑mity to it. Careleſſneſs and in-attention a⯑lone can afford us any remedy. For this reaſon I rely entirely upon them; and take it for granted, whatever may be the reader's opinion at this preſent moment, that an hour hence he will be perſuaded there is both an external and internal world; and going upon that ſuppoſition, I intend to examine ſome general ſyſtems both ancient and modern, which have been propos'd of both, before I proceed to a more particular enquiry concerning our impreſſions. This will not, perhaps, in the end be found fo⯑reign to our preſent purpoſe.

SECT. III. Of the antient philoſophy.

SEVERAL moraliſts have recommended it as an excellent method of becoming acquainted with our own hearts, and know⯑ing our progreſs in virtue, to recollect our dreams in a morning, and examine them with the ſame rigour, that we wou'd our moſt ſerious and moſt deliberate actions. Our character is the ſame throughout, ſay they, and appears beſt where artifice, fear, and policy have no place, and men can neither be hypocrites with themſelves nor others. The generoſity, or baſeneſs of our temper, our meekneſs or cruelty, our courage or puſilanimity, influence the fictions of the imagination with the moſt unbounded li⯑berty, and diſcover themſelves in the moſt glaring colours. In like manner, I am per⯑ſuaded, there might be ſeveral uſeful diſco⯑veries made from a criticiſm of the fictions of the antient philoſophy, concerning ſub⯑ſtances, and ſubſtantial forms, and accidents, and occult qualities; which, however un⯑reaſonable and capricious, have a very in⯑timate [383] connexion with the principles of hu⯑man nature.

'TIS confeſt by the moſt judicious philo⯑ſophers, that our ideas of bodies are nothing but collections form'd by the mind of the ideas of the ſeveral diſtinct ſenſible qualities, of which objects are compos'd, and which we find to have a conſtant union with each o⯑ther. But however theſe qualities may in themſelves be entirely diſtinct, 'tis certain we commonly regard the compound, which they form, as ONE thing, and as continuing the SAME under very conſiderable altera⯑tions. The acknowledg'd compoſition is e⯑vidently contrary to this ſuppos'd ſimplicity, and the variation to the identity. It may, therefore, be worth while to conſider the cauſes, which make us almoſt univerſally fall into ſuch evident contradictions, as well as the means by which we endeavour to conceal them.

'TIS evident, that as the ideas of the ſeveral diſtinct ſucceſſive qualities of objects are united together by a very cloſe relation, the mind, in looking along the ſucceſſion, muſt be carry'd from one part of it to an⯑other by an eaſy tranſition, and will no more perceive the change, than if it contemplated the ſame unchangeable object. This eaſy [384] tranſition is the effect, or rather eſſence of relation; and as the imagination readily takes one idea for another, where their influence on the mind is ſimilar; hence it proceeds, that any ſuch ſucceſſion of related qualities is readily conſider'd as one continu'd object, exiſting without any variation. The ſmooth and uninterrupted progreſs of the thought, being alike in both caſes, readily deceives the mind, and makes us aſcribe an identity to the changeable ſucceſſion of connected qualities.

BUT when we alter our method of con⯑ſidering the ſucceſſion, and inſtead of trace⯑ing it gradually thro' the ſucceſſive points of time, ſurvey at once any two diſtinct periods of its duration, and compare the dif⯑ferent conditions of the ſucceſſive qualities; in that caſe the variations, which were in⯑ſenſible when they aroſe gradually, do now appear of conſequence, and ſeem entirely to deſtroy the identity. By this means there ariſes a kind of contrariety in our method of thinking, from the different points of view, in which we ſurvey the object, and from the nearneſs or remoteneſs of thoſe inſtants of time, which we compare together. When we gradually follow an object in its ſucceſſive changes, the ſmooth progreſs of the thought [385] makes us aſcribe an identity to the ſucceſ⯑ſion; becauſe 'tis by a ſimilar act of the mind we conſider an unchangeable object. When we compare its ſituation after a con⯑ſiderable change the progreſs of the thought is broke; and conſequently we are preſented with the idea of diverſity: In order to re⯑concile which contradictions the imagination is apt to feign ſomething unknown and in⯑viſible, which it ſuppoſes to continue the ſame under all theſe variations; and this unintelligible ſomething it calls a ſubſtance, or original and firſt matter.

WE entertain a like notion with regard to the ſimplicity of ſubſtances, and from like cauſes. Suppoſe an object perfectly ſimple and indiviſible to be preſented, along with another object, whoſe co-exiſtent parts are connected together by a ſtrong relation, 'tis evident the actions of the mind, in conſi⯑dering theſe two objects, are not very different. The imagination conceives the ſimple object at once, with facility, by a ſingle effort of thought, without change or variation. The connexion of parts in the compound object has almoſt the ſame effect, and ſo unites the object within itſelf, that the fancy feels not the tranſition in paſſing from one part to another. Hence the colour, taſte, figure, [386] ſolidity, and other qualities, combin'd in a peach or melon, are conceiv'd to form one thing; and that on account of their cloſe relation, which makes them affect the thought in the ſame manner, as if perfect⯑ly uncompounded. But the mind reſts not here. Whenever it views the object in an⯑other light, it finds that all theſe qualities are different, and diſtinguiſhable, and ſepa⯑rable from each other; which view of things being deſtructive of its primary and more natural notions, obliges the imagination to feign an unknown ſomething, or original ſub⯑ſtance and matter, as a principle of union or coheſion among theſe qualities, and as what may give the compound object a title to be call'd one thing, notwithſtanding its diverſity and compoſition.

THE peripatetic philoſophy aſſerts the original matter to be perfectly homogeneous in all bodies, and conſiders fire, water, earth, and air, as of the very ſame ſubſtance; on account of their gradual revolutions and changes into each other. At the ſame time it aſſigns to each of theſe ſpecies of objects a diſtinct ſubſtantial form, which it ſuppoſes to be the ſource of all thoſe different qua⯑lities they poſſeſs, and to be a new foun⯑dation of ſimplicity and identity to each par⯑icular [387] ſpecies. All depends on our manner of viewing the objects. When we look a⯑long the inſenſible changes of bodies, we ſuppoſe all of them to be of the ſame ſub⯑ſtance or eſſence. When we conſider their ſenſible differences, we attribute to each of them a ſubſtantial and eſſential difference. And in order to indulge ourſelves in both theſe ways of conſidering our objects, we ſuppoſe all bodies to have at once a ſubſtance and a ſubſtantial form.

THE notion of accidents is an unavoid⯑able conſequence of this method of thinking with regard to ſubſtances and ſubſtantial forms; nor can we forbear looking upon colours, ſounds, taſtes, figures, and other properties of bodies, as exiſtences, which can⯑not ſubſiſt apart, but require a ſubject of inhe⯑ſion to ſuſtain and ſupport them. For having never diſcover'd any of theſe ſenſible qualities, where, for the reaſons above mention'd, we did not likewiſe fancy a ſubſtance to exiſt; the ſame habit, which makes us infer a con⯑nexion betwixt cauſe and effect, makes us here infer a dependance of every quality on the unknown ſubſtance. The cuſtom of imagining a dependance has the ſame effect as the cuſtom of obſerving it wou'd have. This conceit, however, is no more reaſon⯑able [388] than any of the foregoing. Every qua⯑lity being a diſtinct thing from another, may be conceiv'd to exiſt apart, and may exiſt apart, not only from every other quality, but from that unintelligible chimera of a ſubſtance.

BUT theſe philoſophers carry their fictions ſtill farther in their ſentiments concerning oc⯑cult qualities, and both ſuppoſe a ſubſtance ſupporting, which they do not underſtand, and an accident ſupported, of which they have as imperfect an idea. The whole ſy⯑ſtem, therefore, is entirely incomprehenſible, and yet is deriv'd from principles as natural as any of theſe above-explain'd.

IN conſidering this ſubject we may ob⯑ſerve a gradation of three opinions, that riſe above each other, according as the per⯑ſons, who form them, acquire new degrees of reaſon and knowledge. Theſe opinions are that of the vulgar, that of a falſe phi⯑loſophy, and that of the true; where we ſhall find upon enquiry, that the true phi⯑loſophy approaches nearer to the ſentiments of the vulgar, than to thoſe of a miſtaken knowledge. 'Tis natural for men, in their common and careleſs way of thinking, to imagine they perceive a connexion betwixt ſuch objects as they have conſtantly found [389] united together; and becauſe cuſtom has render'd it difficult to ſeparate the ideas, they are apt to fancy ſuch a ſeparation to be in itſelf impoſſible and abſurd. But philoſo⯑phers, who abſtract from the effects of cuſ⯑tom, and compare the ideas of objects, im⯑mediately perceive the falſhood of theſe vul⯑gar ſentiments, and diſcover that there is no known connexion among objects. Every dif⯑ferent object appears to them entirely diſtinct and ſeparate; and they perceive, that 'tis not from a view of the nature and qualities of objects we infer one from another, but only when in ſeveral inſtances we obſerve them to have been conſtantly conjoin'd. But theſe philoſophers, inſtead of drawing a juſt in⯑ference from this obſervation, and conclud⯑ing, that we have no idea of power or agency, ſeparate from the mind, and be⯑longing to cauſes; I ſay, inſtead of drawing this concluſion, they frequently ſearch for the qualities, in which this agency conſiſts, and are diſpleas'd with every ſyſtem, which their reaſon ſuggeſts to them, in order to explain it. They have ſufficient force of genius to free them from the vulgar error, that there is a natural and perceivable con⯑nexion betwixt the ſeveral ſenſible qualities and actions of matter; but not ſufficient to [390] keep them from ever ſeeking for this con⯑nexion in matter, or cauſes. Had they fal⯑len upon the juſt concluſion, they wou'd have return'd back to the ſituation of the vulgar, and wou'd have regarded all theſe diſquiſitions with indolence and indifference. At preſent they ſeem to be in a very la⯑mentable condition, and ſuch as the poets have given us but a faint notion of in their deſcriptions of the puniſhment of Siſyphus and Tantalus. For what can be imagin'd more tormenting, than to ſeek with eager⯑neſs, what for ever flies us; and ſeek for it in a place, where 'tis impoſſible it can ever exiſt?

BUT as nature ſeems to have obſerv'd a kind of juſtice and compenſation in every thing, ſhe has not neglected philoſophers more than the reſt of the creation; but has reſerv'd them a conſolation amid all their diſ⯑appointments and afflictions. This conſola⯑tion principally conſiſts in their invention of the words faculty and occult quality. For it being uſual, after the frequent uſe of terms, which are really ſignificant and intelligible, to omit the idea, which we wou'd expreſs by them, and to preſerve only the cuſtom, by which we recal the idea at pleaſure; ſo it naturally happens, that after the frequent uſe [391] of terms, which are wholly inſignificant and unintelligible, we fancy them to be on the ſame footing with the precedent, and to have a ſecret meaning, which we might diſ⯑cover by reflection. The reſemblance of their appearance deceives the mind, as is uſual, and makes us imagine a thorough re⯑ſemblance and conformity. By this means theſe philoſophers ſet themſelves at eaſe, and arrive at laſt, by an illuſion, at the ſame in⯑difference, which the people attain by their ſtupidity, and true philoſophers by their mo⯑derate ſcepticiſm. They need only ſay, that any phaenomenon, which puzzles them, a⯑riſes from a faculty or an occult quality, and there is an end of all diſpute and enquiry upon the matter.

BUT among all the inſtances, wherein the Peripatetics have ſhewn they were guided by every trivial propenſity of the imagination, no one is more remarkable than their ſym⯑pathies, antipathies, and horrors of a vacuum. There is a very remarkable inclination in human nature, to beſtow on external ob⯑jects the ſame emotions, which it obſerves in itſelf; and to find every where thoſe ideas, which are moſt preſent to it. This inclination, 'tis true, is ſuppreſs'd by a little reflection, and only takes place in children, [392] poets, and the antient philoſophers. It ap⯑pears in children, by their deſire of beating the ſtones, which hurt them: In poets, by their readineſs to perſonify every thing: And in the antient philoſophers, by theſe fictions of ſympathy and antipathy. We muſt par⯑don children, becauſe of their age; poets, be⯑cauſe they profeſs to follow implicitly the ſuggeſtions of their fancy: But what ex⯑cuſe ſhall we find to juſtify our philoſophers in ſo ſignal a weakneſs?

SECT. IV. Of the modern philoſophy.

BUT here it may be objected, that the imagination, according to my own confeſſion, being the ultimate judge of all ſyſtems of philoſophy, I am unjuſt in blaming the antient philoſophers for make⯑ing uſe of that faculty, and allowing them⯑ſelves to be entirely guided by it in their reaſonings. In order to juſtify myſelf, I muſt diſtinguiſh in the imagination betwixt the principles which are permanent, irre⯑ſiſtable, and univerſal; ſuch as the cuſto⯑mary tranſition from cauſes to effects, and [393] from effects to cauſes: And the principles, which are changeable, weak, and irregular; ſuch as thoſe I have juſt now taken notice of. The former are the foundation of all our thoughts and actions, ſo that upon their removal human nature muſt immediately periſh and go to ruin. The latter are nei⯑ther unavoidable to mankind, nor neceſſary, or ſo much as uſeful in the conduct of life; but on the contrary are obſerv'd only to take place in weak minds, and being oppoſite to the other principles of cuſtom and reaſon⯑ing, may eaſily be ſubverted by a due con⯑traſt and oppoſition. For this reaſon the former are received by philoſophy, and the latter rejected. One who concludes ſome⯑body to be near him, when he hears an articulate voice in the dark, reaſons juſtly and naturally; tho' that concluſion be de⯑riv'd from nothing but cuſtom, which in⯑fixes and inlivens the idea of a human crea⯑ture, on account of his uſual conjunction with the preſent impreſſion. But one, who is tormented he knows not why, with the apprehenſion of ſpectres in the dark, may, perhaps, be ſaid to reaſon, and to reaſon naturally too: But then it muſt be in the ſame ſenſe, that a malady is ſaid to be na⯑tural; as ariſing from natural cauſes, tho' [394] it be contrary to health, the moſt agreea⯑ble and moſt natural ſituation of man.

THE opinions of the antient philoſo⯑phers, their fictions of ſubſtance and acci⯑dent, and their reaſonings concerning ſub⯑ſtantial forms and occult qualities, are like the ſpectres in the dark, and are deriv'd from principles, which, however common, are neither univerſal nor unavoidable in human nature. The modern philoſophy pretends to be entirely free from this defect, and to a⯑riſe only from the ſolid, permanent, and conſiſtent principles of the imagination. Up⯑on what grounds this pretenſion is founded muſt now be the ſubject of our enquiry.

THE fundamental principle of that phi⯑loſophy is the opinion concerning colours, ſounds, taſtes, ſmells, heat and cold; which it aſſerts to be nothing but impreſſions in the mind, deriv'd from the operation of exter⯑nal objects, and without any reſemblance to the qualities of the objects. Upon examina⯑tion, I find only one of the reaſons com⯑monly produc'd for this opinion to be ſatis⯑factory, viz. that deriv'd from the varia⯑tions of thoſe impreſſions, even while the external object, to all appearance, continues the ſame. Theſe variations depend upon ſeveral circumſtances. Upon the different [395] ſituations of our health: A man in a mala⯑dy feels a diſagreeable taſte in meats, which before pleas'd him the moſt. Upon the different complexions and conſtitutions of men: That ſeems bitter to one, which is ſweet to another. Upon the difference of their external ſituation and poſition: Colours reflected from the clouds change according to the diſtance of the clouds, and accord⯑ing to the angle they make with the eye and luminous body. Fire alſo communicates the ſenſation of pleaſure at one diſtance, and that of pain at another. Inſtances of this kind are very numerous and frequent.

THE concluſion drawn from them, is likewiſe as ſatisfactory as can poſſibly be imagin'd. 'Tis certain, that when different impreſſions of the ſame ſenſe ariſe from any object, every one of theſe impreſſions has not a reſembling quality exiſtent in the ob⯑ject. For as the ſame object cannot, at the ſame time, be endow'd with different qua⯑lities of the ſame ſenſe, and as the ſame qua⯑lity cannot reſemble impreſſions entirely dif⯑ferent; it evidently follows, that many of our impreſſions have no external model or archetype. Now from like effects we pre⯑ſume like cauſes. Many of the impreſſions of colour, ſound, &c. are confeſt to be no⯑thing [396] but internal exiſtences, and to ariſe from cauſes, which no ways reſemble them. Theſe impreſſions are in appearance no⯑thing different from the other impreſſions of colour, ſound, &c. We conclude, there⯑fore, that they are, all of them, deriv'd from a like origin.

THIS principle being once admitted, all the other doctrines of that philoſophy ſeem to follow by an eaſy conſequence. For upon the removal of ſounds, colours, heat, cold, and other ſenſible qualities, from the rank of continu'd independent exiſtences, we are reduc'd merely to what are called primary qualities, as the only real ones, of which we have any adequate notion. Theſe primary qualities are extenſion and ſolidi⯑ty, with their different mixtures and modi⯑fications; figure, motion, gravity, and cohe⯑ſion. The generation, encreaſe, decay, and corruption of animals and vegetables, are nothing but changes of figure and motion; as alſo the operations of all bodies on each o⯑ther; of fire, of light, water, air, earth, and of all the elements and powers of nature. One figure and motion produces another figure and motion; nor does there remain in the material univerſe any other principle, either [397] active or paſſive, of which we can form the moſt diſtant idea.

I BELIEVE many objections might be made to this ſyſtem: But at preſent I ſhall confine myſelf to one, which is in my opi⯑nion very deciſive. I aſſert, that inſtead of explaining the operations of external ob⯑jects by its means, we utterly annihilate all theſe objects, and reduce ourſelves to the opinions of the moſt extravagant ſcepticiſm concerning them. If colours, ſounds, taſtes, and ſmells be merely perceptions, nothing we can conceive is poſſeſt of a real, con⯑tinu'd, and independent exiſtence; not even motion, extenſion and ſolidity, which are the primary qualities chiefly inſiſted on.

TO begin with the examination of mo⯑tion; 'tis evident this is a quality altogether inconceivable alone, and without a reference to ſome other object. The idea of motion neceſſarily ſuppoſes that of a body moving. Now what is our idea of the moving body, without which motion is incomprehenſible? It muſt reſolve itſelf into the idea of ex⯑tenſion or of ſolidity; and conſequently the reality of motion depends upon that of theſe other qualities.

THIS opinion, which is univerſally ac⯑knowledg'd concerning motion, I have [398] prov'd to be true with regard to extenſion; and have ſhewn that 'tis impoſſible to con⯑ceive extenſion, but as compo'd of parts, endow'd with colour or ſolidity. The idea of extenſion is a compound idea; but as it is not compounded of an infinite number of parts or inferior ideas, it muſt at laſt re⯑ſolve itſelf into ſuch as are perfectly ſimple and indiviſible. Theſe ſimple and indiviſi⯑ble parts, not being ideas of extenſion, muſt be non-entities, unleſs conceiv'd as colour'd or ſolid. Colour is excluded from any real exiſtence. The reality, therefore, of our idea of extenſion depends upon the reality of that of ſolidity, nor can the former be juſt while the latter is chimerical. Let us, then, lend our attention to the examination of the idea of ſolidity.

THE idea of ſolidity is that of two ob⯑jects, which being impell'd by the utmoſt force, cannot penetrate each other; but ſtill maintain a ſeparate and diſtinct exiſtence. Solidity, therefore, is perfectly incomprehenſi⯑ble alone, and without the conception of ſome bodies, which are ſolid, and maintain this ſeparate and diſtinct exiſtence. Now what idea have we of theſe bodies? The ideas of colours, ſounds, and other ſecondary qualities are excluded. The idea of mo⯑tion [399] depends on that of extenſion, and the idea of extenſion on that of ſolidity. 'Tis impoſſible, therefore, that the idea of ſoli⯑dity can depend on either of them. For that wou'd be to run in a circle, and make one idea depend on another, while at the ſame time the latter depends on the former. Our modern philoſophy, therefore, leaves us no juſt nor ſatisfactory idea of ſolidity; nor conſequently of matter.

THIS argument will appear entirely con⯑cluſive to every one that comprehends it; but becauſe it may ſeem abſtruſe and intri⯑cate to the generality of readers, I hope to be excus'd, if I endeavour to render it more obvious by ſome variation of the expreſſion. In order to form an idea of ſolidity, we muſt conceive two bodies preſſing on each other without any penetration; and 'tis im⯑poſſible to arrive at this idea, when we confine ourſelves to one object, much more without conceiving any. Two non-entities cannot ex⯑clude each other from their places; becauſe they never poſſeſs any place, nor can be endow'd with any quality. Now I aſk, what idea do we form of theſe bodies or objects, to which we ſuppoſe ſolidity to be⯑long? To ſay, that we conceive them mere⯑ly as ſolid, is to run on in infinitum. To [400] affirm, that we paint them out to ourſelves as extended, either reſolves all into a falſe idea, or returns in a circle. Extenſion muſt neceſſarily be conſider'd either as colour'd, which is a falſe idea; or as ſolid, which brings us back to the firſt queſtion. We may make the ſame obſervation concerning mobility and figure; and upon the whole muſt conclude, that after the excluſion of colours, ſounds, heat and cold from the rank of external exiſtences, there remains nothing, which can afford us a juſt and con⯑ſiſtent idea of body.

ADD to this, that, properly ſpeaking, ſolidity or impenetrability is nothing, but an impoſſibility of annihilation, as ^* has been already obſerv'd: For which reaſon 'tis the more neceſſary for us to form ſome diſtinct idea of that object, whoſe annihila⯑tion we ſuppoſe impoſſible. An impoſſibi⯑lity of being annihilated cannot exiſt, and can never be conceived to exiſt, by itſelf; but neceſſarily requires ſome object or real exiſtence, to which it may belong. Now the difficulty ſtill remains, how to form an idea of this object or exiſtence, without having recourſe to the ſecondary and ſenſi⯑ble qualities.

[401] NOR muſt we omit on this occaſion our accuſtom'd method of examining ideas by conſidering thoſe impreſſions, from which they are deriv'd. The impreſſions, which enter by the ſight and hearing, the ſmell and taſte, are affirm'd by modern philoſophy to be without any reſembling objects; and con⯑ſequently the idea of ſolidity, which is ſuppos'd to be real, can never be deriv'd from any of theſe ſenſes. There remains, therefore, the feeling as the only ſenſe, that can convey the impreſſion, which is original to the idea of ſolidity; and indeed we na⯑turally imagine, that we feel the ſolidity of bodies, and need but touch any object in or⯑der to perceive this quality. But this me⯑thod of thinking is more popular than phi⯑loſophical; as will appear from the follow⯑ing reflections.

FIRST, 'Tis eaſy to obſerve, that tho' bodies are felt by means of their ſolidity, yet the feeling is a quite different thing from the ſolidity; and that they have not the leaſt reſemblance to each other. A man, who has the palſey in one hand, has as per⯑fect an idea of impenetrability, when he obſerves that hand to be ſupported by the table, as when he feels the ſame table with the other hand. An object, that preſſes upon [402] any of our members, meets with reſiſtance; and that reſiſtance, by the motion it gives to the nerves and animal ſpirits, conveys a cer⯑tain ſenſation to the mind; but it does not follow, that the ſenſation, motion, and reſi⯑ſtance are any ways reſembling.

SECONDLY, The impreſſions of touch are ſimple impreſſions, except when conſider'd with regard to their extenſion; which makes nothing to the preſent purpoſe: And from this ſimplicity I infer, that they neither re⯑preſent ſolidity, nor any real object. For let us put two caſes, viz. that of a man, who preſſes a ſtone, or any ſolid body, with his hand, and that of two ſtones, which preſſes each other; 'twill readily be allow'd, that theſe two caſes are not in every reſpect alike, but that in the former there is con⯑join'd with the ſolidity, a feeling or ſenſa⯑tion, of which there is no appearance in the latter. In order, therefore, to make theſe two caſes alike, 'tis neceſſary to remove ſome part of the impreſſion, which the man feels by his hand, or organ of ſenſation; and that being impoſſible in a ſimple im⯑preſſion, obliges us to remove the whole, and proves that this whole impreſſion has no archetype or model in external objects. To which we may add, that ſolidity neceſ⯑ſarily [403] ſuppoſes two bodies, along with con⯑tiguity and impulſe; which being a com⯑pound object, can never be repreſented by a ſimple impreſſion. Not to mention, that tho' ſolidity continues always invariably the ſame, the impreſſions of touch change eve⯑ry moment upon us; which is a clear proof that the latrer are not repreſentations of the former.

THUS there is a direct and total oppo⯑ſition betwixt our reaſon and our ſenſes; or more properly ſpeaking, betwixt thoſe con⯑cluſions we form from cauſe and effect, and thoſe that perſuade us of the continu'd and independent exiſtence of body. When we reaſon from cauſe and effect, we con⯑clude, that neither colour, ſound, taſte, nor ſmell have a continu'd and independent exiſ⯑tence. When we exclude theſe ſenſible qualities there remains nothing in the uni⯑verſe, which has ſuch an exiſtence.

SECT. V. Of the immateriality of the ſoul.

HAVING found ſuch contradicti⯑ons and difficulties in every ſyſtem concerning external objects, and in the idea of matter, which we fancy ſo clear and de⯑terminate, we ſhall naturally expect ſtill greater difficulties and contradictions in eve⯑ry hypotheſis concerning our internal per⯑ceptions, and the nature of the mind, which we are apt to imagine ſo much more ob⯑ſcure, and uncertain. But in this we ſhou'd deceive ourſelves. The intellectual world, tho' involv'd in infinite obſcurities, is not perplex'd with any ſuch contradictions, as thoſe we have diſcover'd in the natu⯑ral. What is known concerning it, agrees with itſelf; and what is unknown, we muſt be contented to leave ſo.

'TIS true, wou'd we hearken to certain philoſophers, they promiſe to diminiſh our ignorance; but I am afraid 'tis at the ha⯑zard of running us into contradictions, from which the ſubject is of itſelf exempted. Theſe philoſophers are the curious reaſoners concerning the material or immaterial ſub⯑ſtances, [405] in which they ſuppoſe our percep⯑tions to inhere. In order to put a ſtop to theſe endleſs cavils on both ſides, I know no better method, than to aſk theſe philo⯑ſophers in a few words, What they mean by ſubſtance and inheſion? And after they have anſwer'd this queſtion, 'twill then be reaſon⯑able, and not till then, to enter ſeriouſly in⯑to the diſpute.

THIS queſtion we have found impoſſi⯑ble to be anſwer'd with regard to matter and body: But beſides that in the caſe of the mind, it labours under all the ſame dif⯑ficulties, 'tis burthen'd with ſome additional ones, which are peculiar to that ſubject. As every idea is deriv'd from a precedent im⯑preſſion, had we any idea of the ſubſtance of our minds, we muſt alſo have an impreſſion of it; which is very difficult, if not impoſ⯑ſible, to be conceiv'd. For how can an impreſſion repreſent a ſubſtance, otherwiſe than by reſembling it? And how can an im⯑preſſion reſemble a ſubſtance, ſince, accord⯑ing to this philoſophy, it is not a ſubſtance, and has none of the peculiar qualities or characteriſtics of a ſubſtance?

BUT leaving the queſtion of what may or may not be, for that other what actually is, I deſire thoſe philoſophers, who pretend [406] that we have an idea of the ſubſtance of our minds, to point out the impreſſion that produces it, and tell diſtinctly after what manner that impreſſion operates, and from what object it is deriv'd. Is it an impreſſion of ſenſation or of reflection? Is it pleaſant, or painful, or indifferent? Does it attend us at all times, or does it only return at inter⯑vals? If at intervals, at what times princi⯑pally does it return, and by what cauſes is it produc'd?

IF inſtead of anſwering theſe queſtions, any one ſhou'd evade the difficulty, by ſay⯑ing, that the definition of a ſubſtance is ſomething which may exiſt by itſelf; and that this definition ought to ſatisfy us: Shou'd this be ſaid, I ſhou'd obſerve, that this de⯑finition agrees to every thing, that can poſ⯑ſibly be conceiv'd; and never will ſerve to diſtinguiſh ſubſtance from accident, or the ſoul from its perceptions. For thus I reaſon. Whatever is clearly conceiv'd may exiſt; and whatever is clearly conceiv'd, after any manner, may exiſt after the ſame manner. This is one principle, which has been al⯑ready acknowledg'd. Again, every thing, which is different, is diſtinguiſhable, and every thing which is diſtinguiſhable, is ſe⯑parable by the imagination. This is ano⯑ther [407] principle. My concluſion from both is, that ſince all our perceptions are different from each other, and from every thing elſe in the univerſe, they are alſo diſtinct and ſeparable, and may be conſider'd as ſepa⯑rately exiſtent, and may exiſt ſeparately, and have no need of any thing elſe to ſup⯑port their exiſtence. They are, therefore, ſubſtances, as far as this definition explains a ſubſtance.

THUS neither by conſidering the firſt origin of ideas, nor by means of a defini⯑tion are we able to arrive at any ſatisfactory notion of ſubſtance; which ſeems to me a ſufficient reaſon for abandoning utterly that diſpute concerning the materiality and im⯑materiality of the ſoul, and makes me abſo⯑lutely condemn even the queſtion itſelf. We have no perfect idea of any thing but of a perception. A ſubſtance is entirely dif⯑ferent from a perception. We have, there⯑fore, no idea of a ſubſtance. Inheſion in ſomething is ſuppos'd to be requiſite to ſup⯑port the exiſtence of our perceptions. No⯑thing appears requiſite to ſupport the exiſ⯑tence of a perception. We have, therefore, no idea of inheſion. What poſſibility then of anſwering that queſtion, Whether percep⯑tions inhere in a material or immaterial ſub⯑ſtance, [408] when we do not ſo much as under⯑ſtand the meaning of the queſtion?

THERE is one argument commonly em⯑ploy'd for the immateriality of the ſoul, which ſeems to me remarkable. Whatever is extend⯑ed conſiſts of parts; and whatever conſiſts of parts is diviſible, if not in reality, at leaſt in the imagination. But 'tis impoſſible any thing diviſible can be conjoin'd to a thought or perception, which is a being altogether inſeparable and indiviſible. For ſuppoſing ſuch a conjunction, wou'd the indiviſible though exiſt on the left or on the right hand of this extended diviſible body? On the ſurface or in the middle? On the back⯑or fore-ſide of it? If it be conjoin'd with the extenſion, it muſt exiſt ſomewhere with⯑in its dimenſions. If it exiſt within its di⯑menſions, it muſt either exiſt in one parti⯑cular part; and then that particular part is indiviſible, and the perception is conjoin'd only with it, not with the extenſion: Or if the thought exiſts in every part, it muſt al⯑ſo be extended, and ſeparable, and diviſible, as well as the body; which is utterly ab⯑ſurd and contradictory. For can any one conceive a paſſion of a yard in length, a foot in breadth, and an inch in thickneſs? Thought, therefore, and extenſion are qua⯑lities [409] wholly incompatible, and never can incorporate together into one ſubject.

THIS argument affects not the queſtion concerning the ſubſtance of the ſoul, but on⯑ly that concerning its local conjunction with matter; and therefore it may not be impro⯑per to conſider in general what objects are, or are not ſuſceptible of a local conjunction. This is a curious queſtion and may lead us to ſome diſcoveries of conſiderable moment.

THE firſt notion of ſpace and extenſion is deriv'd ſolely from the ſenſes of ſight and feeling; nor is there any thing, but what is colour'd or tangible, that has parts diſpos'd after ſuch a manner, as to convey that idea. When we diminiſh or encreaſe a reliſh, 'tis not after the ſame manner that we diminiſh or increaſe any viſible object; and when ſeveral ſounds ſtrike our hearing at once, cuſtom and reflection alone make us form an idea of the degrees of the diſtance and contiguity of thoſe bodies, from which they are deriv'd. Whatever marks the place of its exiſtence either muſt be extended, or muſt be a mathematical point, without parts or compoſition. What is extended muſt have a particular figure, as ſquare, round, triangular; none of which will agree to a deſire, or indeed to any impreſſion or idea, [410] except of theſe two ſenſes above-men⯑tion'd. Neither ought a deſire, tho' indivi⯑ſible, to be conſider'd as a mathematical point. For in that caſe 'twou'd be poſſible, by the addition of others, to make two, three, four deſires, and theſe diſpos'd and ſituated in ſuch a manner, as to have a determinate length, breadth and thickneſs; which is e⯑vidently abſurd.

'TWILL not be ſurprizing after this, if I deliver a maxim, which is condemn'd by ſeveral metaphyſicians, and is eſteem'd con⯑trary to the moſt certain principles of hu⯑man reaſon. This maxim is that an object may exiſt, and yet be no where: and I aſ⯑ſert, that this is not only poſſible, but that the greateſt part of beings do and muſt ex⯑iſt after this manner. An object may be ſaid to be no where, when its parts are not ſo ſituated with reſpect to each other, as to form any figure or quantity; nor the whole with reſpect to other bodies ſo as to anſwer to our notions of contiguity or diſtance. Now this is evidently the caſe with all our perceptions and objects, except thoſe of the ſight and feeling. A moral reflection can⯑not be plac'd on the right or on the left hand of a paſſion, nor can a ſmell or ſound be either of a circular or a ſquare figure. [411] Theſe objects and perceptions, ſo far from requiring any particular place, are abſolutely incompatible with it, and even the imagi⯑nation cannot attribute it to them. And as to the abſurdity of ſuppoſing them to be no where, we may conſider, that if the paſſions and ſentiments appear to the per⯑ception to have any particular place, the idea of extenſion might be deriv'd from them, as well as from the ſight and touch; con⯑trary to what we have already eſtabliſh'd. If they appear not to have any particular place, they may poſſibly exiſt in the ſame manner; ſince whatever we conceive is poſ⯑ſible.

'TWILL not now be neceſſary to prove, that thoſe perceptions, which are ſimple, and exiſt no where, are incapable of any con⯑junction in place with matter or body, which is extended and diviſible; ſince 'tis impoſſible to found a relation ^* but on ſome common quality. It may be better worth our while to remark, that this queſtion of the local conjunction of objects does not only occur in metaphyſical diſputes concern⯑ing the nature of the ſoul, but that even in common life we have every moment oc⯑caſion to examine it. Thus ſuppoſing we [412] conſider a fig at one end of the table, and an olive at the other, 'tis evident, that in forming the complex ideas of theſe ſub⯑ſtances, one of the moſt obvious is that of their different reliſhes; and 'tis as evident, that we incorporate and conjoin theſe qua⯑lities with ſuch as are colour'd and tangible. The bitter taſte of the one, and ſweet of the other are ſuppos'd to lie in the very vi⯑ſible body, and to be ſeparated from each other by the whole length of the table. This is ſo notable and ſo natural an illuſion, that it may be proper to conſider the prin⯑ciples, from which it is deriv'd.

THO' an extended object be incapable of a conjunction in place with another, that exiſts without any place or extenſion, yet are they ſuſceptible of many other relations. Thus the taſte and ſmell of any fruit are inſeparable from its other qualities of colour and tangibility; and which-ever of them be the cauſe or effect, 'tis certain they are al⯑ways co-exiſtent. Nor are they only co-exiſtent in general, but alſo co-temporary in their appearance in the mind; and 'tis upon the application of the extended body to our ſenſes we perceive its particular taſte and ſmell. Theſe relations, then, of cauſation, and contiguity in the time of their appear⯑ance, [413] betwixt the extended object and the quality, which exiſts without any particular place, muſt have ſuch an effect on the mind, that upon the appearance of one it will im⯑mediately turn its thought to the conception of the other. Nor is this all. We not only turn our thought from one to the other upon account of their relation, but likewiſe en⯑deavour to give them a new relation, viz. that of a conjunction in place, that we may render the tranſition more eaſy and natural. For 'tis a quality, which I ſhall often have occaſion to remark in human nature, and ſhall explain more fully in its proper place, that when objects are united by any rela⯑tion, we have a ſtrong propenſity to add ſome new relation to them, in order to com⯑pleat the union. In our arrangement of bo⯑dies we never fail to place ſuch as are re⯑ſembling, in contiguity to each other, or at leaſt in correſpondent points of view: Why? but becauſe we feel a ſatisfaction in joining the relation of contiguity to that of reſem⯑blance, or the reſemblance of ſituation to that of qualities. The effects of this pro⯑penſity have been ^* already obſerv'd in that reſemblance, which we ſo readily ſuppoſe betwixt particular impreſſions and their ex⯑ternal [414] cauſes. But we ſhall not find a more evident effect of it, than in the preſent in⯑ſtance, where from the relations of cauſa⯑tion and contiguity in time betwixt two objects, we feign likewiſe that of a con⯑junction in place, in order to ſtrengthen the connextion.

BUT whatever confus'd notions we may form of an union in place betwixt an ex⯑tended body, as a fig, and its particular taſte, 'tis certain that upon reflection we muſt ob⯑ſerve in this union ſomething altogether un⯑intelligible and contradictory. For ſhou'd we aſk ourſelves one obvious queſtion, viz. if the taſte, which we conceive to be con⯑tain'd in the circumference of the body, is in every part of it or in one only, we muſt quickly find ourſelves at a loſs, and perceive the impoſſibility of ever giving a ſatisfactory anſwer. We cannot reply, that 'tis only in one part: For experience convinces us, that every part has the ſame reliſh. We can as little reply, that it exiſts in every part: For then we muſt ſuppoſe it figur'd and extended; which is abſurd and incompre⯑henſible. Here then we are influenc'd by two principles directly contrary to each o⯑ther, viz. that inclination of our fancy by which we are determin'd to incorporate the [415] taſte with the extended object, and our rea⯑ſon, which ſhows us the impoſſibility of ſuch an union. Being divided betwixt theſe op⯑poſite principles, we renounce neither one nor the other, but involve the ſubject in ſuch confuſion and obſcurity, that we no longer perceive the oppoſition. We ſup⯑poſe, that the taſte exiſts within the cir⯑cumference of the body, but in ſuch a manner, that it fills the whole without ex⯑tenſion, and exiſts entire in every part with⯑out ſeparation. In ſhort, we uſe in our moſt familiar way of thinking, that ſcholaſtic prin⯑ciple, which, when crudely propos'd, appears ſo ſhocking, of totum in toto & totum in qua⯑libet parte: Which is much the ſame, as if we ſhou'd ſay, that a thing is in a certain place, and yet is not there.

ALL this abſurdity proceeds from our en⯑deavouring to beſtow a place on what is utterly incapable of it; and that endeavour again ariſes from our inclination to compleat an union, which is founded on cauſation, and a contiguity of time, by attributing to the objects a conjunction in place. But if ever reaſon be of ſufficient force to over⯑come prejudice, 'tis certain, that in the pre⯑ſent caſe it muſt prevail. For we have only this choice left, either to ſuppoſe that ſome be⯑ings [416] ings exiſt without any place; or that they are figur'd and extended; or that when they are incorporated with extended objects, the whole is in the whole, and the whole in every part. The abſurdity of the two laſt ſuppoſitions proves ſufficiently the veracity of the firſt. Nor is there any fourth opi⯑nion. For as to the ſuppoſition of their ex⯑iſtence in the manner of mathematical points, it reſolves itſelf into the ſecond opinion, and ſuppoſes, that ſeveral paſſions may be plac'd in a circular figure, and that a certain num⯑ber of ſmells, conjoin'd with a certain num⯑ber of ſounds, may make a body of twelve cubic inches; which appears ridiculous upon the bare mentioning of it.

BUT tho' in this view of things we can⯑not refuſe to condemn the materialiſts, who conjoin all thought with extenſion; yet a little reflection will ſhow us equal reaſon for blam⯑ing their antagoniſts, who conjoin all thought with a ſimple and indiviſible ſubſtance. The moſt vulgar philoſophy informs us, that no external object can make itſelf known to the mind immediately, and without the interpoſition of an image or perception. That table, which juſt now appears to me, is only a perception, and all its qualities are qualities of a perception. Now the moſt [417] obvious of all its qualities is extenſion. The perception conſiſts of parts. Theſe parts are ſo ſituated, as to afford us the notion of diſtance and contiguity; of length, breadth, and thickneſs. The termination of theſe three dimenſions is what we call figure. This figure is moveable, ſeparable, and divi⯑ſible. Mobility, and ſeparability are the diſtin⯑guiſhing properties of extended objects. And to cut ſhort all diſputes, the very idea of extenſion is copy'd from nothing but an impreſſion, and conſequently muſt perfectly agree to it. To ſay the idea of extenſion agrees to any thing, is to ſay it is extended.

THE free-thinker may now triumph in his turn; and having found there are impreſ⯑ſions and ideas really extended, may aſk his antagoniſts, how they can incorporate a ſimple and indiviſible ſubject with an ex⯑tended perception? All the arguments of Theologians may here be retorted upon them. Is the indiviſible ſubject, or immaterial ſub⯑ſtance, if you will, on the left or on the right hand of the perception? Is it in this particular part, or in that other? Is it in every part without being extended? Or is it entire in any one part without deſerting the reſt? 'Tis impoſſible to give any anſwer to theſe queſtions, but what will both be ab⯑ſurd [418] in itſelf, and will account for the union of our indiviſible perceptions with an extend⯑ed ſubſtance.

THIS gives me an occaſion to take a-new into conſideration the queſtion concerning the ſubſtance of the ſoul; and tho' I have con⯑demn'd that queſtion as utterly unintelligible, yet I cannot forbear propoſing ſome farther reflections concerning it. I aſſert, that the doctrine of the immateriality, ſimplicity, and indiviſibility of a thinking ſubſtance is a true atheiſm, and will ſerve to juſtify all thoſe ſentiments, for which Spinoza is ſo univer⯑ſally infamous. From this topic, I hope at leaſt to reap one advantage, that my adver⯑ſaries will not have any pretext to render the preſent doctrine odious by their decla⯑mations, when they ſee that they can be ſo eaſily retorted on them.

THE fundamental principle of the athe⯑iſm of Spinoza is the doctrine of the ſim⯑plicity of the univerſe, and the unity of that ſubſtance, in which he ſuppoſes both thought and matter to inhere. There is only one ſubſtance, ſays he, in the world; and that ſubſtance is perfectly ſimple and indiviſible, and exiſts every where, without any local preſence. Whatever we diſcover externally [419] by ſenſation; whatever we feel internally by reflection; all theſe are nothing but mo⯑difications of that one, ſimple, and neceſſa⯑rily exiſtent being, and are not poſſeſt of any ſeparate or diſtinct exiſtence. Every paſſion of the ſoul; every configuration of matter, however different and various, in⯑here in the ſame ſubſtance, and preſerve in themſelves their characters of diſtinction, without communicating them to that ſubject, in which they inhere. The ſame ſubſtratum, if I may ſo ſpeak, ſupports the moſt dif⯑ferent modifications, without any difference in itſelf; and varies them, without any va⯑riation. Neither time, nor place, nor all the diverſity of nature are able to produce any compoſition or change in its perfect ſimpli⯑city and identity.

I BELIEVE this brief expoſition of the principles of that famous atheiſt will be ſuf⯑ficient for the preſent purpoſe, and that without entering farther into theſe gloomy and obſcure regions, I ſhall be able to ſhew, that this hideous hypotheſis is almoſt the ſame with that of the immateriality of the ſoul, which has become ſo popular. To make this evident, let us ^* remember, that [420] as every idea is deriv'd from a preceding perception, 'tis impoſſible our idea of a per⯑ception, and that of an object or external exiſtence can ever repreſent what are ſpeci⯑fically different from each other. Whatever difference we may ſuppoſe betwixt them, 'tis ſtill incomprehenſible to us; and we are oblig'd either to conceive an external object merely as a relation without a relative, or to make it the very ſame with a perception or impreſſion.

THE conſequence I ſhall draw from this may, at firſt ſight, appear a mere ſophiſm; but upon the leaſt examination will be found ſolid and ſatisfactory. I ſay then, that ſince we may ſuppoſe, but never can conceive a ſpecific difference betwixt an object and im⯑preſſion; any concluſion we form concern⯑ing the connexion and repugnance of im⯑preſſions, will not be known certainly to be applicable to objects; but that on the other hand, whatever concluſions of this kind we form concerning objects, will moſt certainly be applicable to impreſſions. The reaſon is not difficult. As an object is ſuppos'd to be different from an impreſſion, we cannot be ſure, that the circumſtance, upon which we found our reaſoning, is common to both, ſuppoſing we form the reaſoning upon the [421] impreſſion. 'Tis ſtill poſſible, that the ob⯑ject may differ from it in that particular. But when we firſt form our reaſoning con⯑cerning the object, 'tis beyond doubt, that the ſame reaſoning muſt extend to the impreſ⯑ſion: And that becauſe the quality of the object, upon which the argument is founded, muſt at leaſt be conceiv'd by the mind; and cou'd not be conceiv'd, unleſs it were com⯑mon to an impreſſion; ſince we have no idea but what is deriv'd from that origin. Thus we may eſtabliſh it as a certain maxim, that we can never, by any principle, but by an irregular kind ^* of reaſoning from experi⯑ence, diſcover a connexion or repugnance betwixt objects, which extends not to im⯑preſſions; tho' the inverſe propoſition may not be equally true, that all the diſcoverable relations of impreſſions are common to ob⯑jects.

To apply this to the preſent caſe; there are two different ſyſtems of beings preſented, to which I ſuppoſe myſelf under a neceſſity of aſſigning ſome ſubſtance, or ground of inheſion. I obſerve firſt the univerſe of ob⯑jects or of body: The ſun, moon and ſtars; the earth, ſeas, plants, animals, men, ſhips, [422] houſes, and other productions either of art or nature. Here Spinoza appears, and tells me, that theſe are only modifications; and that the ſubject, in which they inhere, is ſimple, incompounded, and indiviſible. After this I conſider the other ſyſtem of beings, viz. the univerſe of thought, or my impreſ⯑ſions and ideas. There I obſerve another ſun, moon and ſtars; an earth, and ſeas, cover'd and inhabited by plants and ani⯑mals; towns, houſes, mountains, rivers; and in ſhort every thing I can diſcover or con⯑ceive in the firſt ſyſtem. Upon my en⯑quiring concerning theſe, Theologians pre⯑ſent themſelves, and tell me, that theſe alſo are modifications, and modifications of one ſimple, uncompounded, and indiviſible ſub⯑ſtance. Immediately upon which I am deafen'd with the noiſe of a hundred voices, that treat the firſt hypotheſis with deteſta⯑tion and ſcorn, and the ſecond with ap⯑plauſe and veneration. I turn my attention to theſe hypotheſes to ſee what may be the reaſon of ſo great a partiality; and find that they have the ſame fault of being unintel⯑ligible, and that as far as we can under⯑ſtand them, they are ſo much alike, that 'tis impoſſible to diſcover any abſurdity in one, which is not common to both of them. We [423] have no idea of any quality in an object, which does not agree to, and may not re⯑preſent a quality in an impreſſion; and that becauſe all our ideas are deriv'd from our impreſſions. We can never, therefore, find any repugnance betwixt an extended object as a modification, and a ſimple uncom⯑pounded eſſence, as its ſubſtance, unleſs that repugnance takes place equally betwixt the perception or impreſſion of that extended object, and the ſame uncompounded eſſence. Every idea of a quality in an object paſſes thro' an impreſſion; and therefore every per⯑ceivable relation, whether of connexion or repugnance, muſt be common both to ob⯑jects and impreſſions.

BUT tho' this argument, conſider'd in general, ſeems evident beyond all doubt and contradiction, yet to make it more clear and ſenſible, let us ſurvey it in detail; and ſee whether all the abſurdities, which have been found in the ſyſtem of Spinoza, may not like⯑wiſe be diſcover'd in that of Theologians ^*.

FIRST, It has been ſaid againſt Spinoza, according to the ſcholaſtic way of talking, rather than thinking, that a mode, not be⯑ing any diſtinct or ſeparate exiſtence, muſt be the very ſame with its ſubſtance, and [424] conſequently the extenſion of the univerſe, muſt be in a manner identify'd with that ſimple, uncompounded eſſence, in which the univerſe is ſuppos'd to inhere. But this, it may be pretended, is utterly impoſſible and inconceivable unleſs the indiviſible ſubſtance expand itſelf, ſo as to correſpond to the extenſion, or the extenſion contract itſelf, ſo as to anſwer to the indiviſible ſubſtance. This argument ſeems juſt, as far as we can underſtand it; and 'tis plain nothing is re⯑quir'd, but a change in the terms, to apply the ſame argument to our extended percep⯑tions, and the ſimple eſſence of the ſoul; the ideas of objects and perceptions being in every reſpect the ſame, only attended with the ſuppoſition of a difference, that is un⯑known and incomprehenſible.

SECONDLY, It has been ſaid, that we have no idea of ſubſtance, which is not applicable to matter; nor any idea of a diſ⯑tinct ſubſtance, which is not applicable to every diſtinct portion of matter. Matter, therefore, is not a mode but a ſubſtance, and each part of matter is not a diſtinct mode, but a diſtinct ſubſtance. I have al⯑ready prov'd, that we have no perfect idea of ſubſtance; but that taking it for ſome⯑thing, that can exiſt by itſelf, 'tis evident [425] every perception is a ſubſtance, and every diſtinct part of a perception a diſtinct ſub⯑ſtance: And conſequently the one hypo⯑theſis labours under the ſame difficulties in this reſpect with the other.

THIRDLY, It has been objected to the ſyſtem of one ſimple ſubſtance in the uni⯑verſe, that this ſubſtance being the ſupport or ſubſtratum of every thing, muſt at the very ſame inſtant be modify'd into forms, which are contrary and incompatible. The round and ſquare figures are incompatible in the ſame ſubſtance at the ſame time. How then is it poſſible, that the ſame ſub⯑ſtance can at once be modify'd into that ſquare table, and into this round one? I aſk the ſame queſtion concerning the impreſſions of theſe tables; and find that the anſwer is no more ſatisfactory in one caſe than in the other.

IT appears, then, that to whatever ſide we turn, the ſame difficulties follow us, and that we cannot advance one ſtep towards the eſtabliſhing the ſimplicity and immate⯑riality of the ſoul, without preparing the way for a dangerous and irrecoverable atheiſm. 'Tis the ſame caſe, if inſtead of calling thought a modification of the ſoul, we ſhou'd give it the more antient, and yet more modiſh name of an action. By an [426] action we mean much the ſame thing, as what is commonly call'd an abſtract mode; that is, ſomething, which, properly ſpeak⯑ing, is neither diſtinguiſhable, nor ſeparable from its ſubſtance, and is only conceiv'd by a diſtinction of reaſon, or an abſtraction. But nothing is gain'd by this change of the term of modification, for that of action; nor do we free ourſelves from one ſingle difficulty by its means; as will appear from the two following reflections.

FIRST, I obſerve, that the word, action, according to this explication of it, can never juſtly be apply'd to any perception, as de⯑riv'd from a mind or thinking ſubſtance. Our perceptions are all really different, and ſeparable, and diſtinguiſhable from each o⯑ther, and from every thing elſe, which we can imagine; and therefore 'tis impoſſible to conceive, how they can be the action or ab⯑ſtract mode of any ſubſtance. The inſtance of motion, which is commonly made uſe of to ſhew after what manner perception de⯑pends, as an action, upon its ſubſtance, ra⯑ther confounds than inſtructs us. Motion to all appearance induces no real nor eſſen⯑tial change on the body, but only varies its relation to other objects. But betwixt a perſon in the morning walking in a garden [427] with company, agreeable to him; and a perſon in the afternoon inclos'd in a dun⯑geon, and full of terror, deſpair, and reſent⯑ment, there ſeems to be a radical difference, and of quite another kind, than what is produc'd on a body by the change of its ſi⯑tuation. As we conclude from the diſtinc⯑tion and ſeparability of their ideas, that ex⯑ternal objects have a ſeparate exiſtence from each other; ſo when we make theſe ideas themſelves our objects, we muſt draw the ſame concluſion concerning them, accord⯑ing to the precedent reaſoning. At leaſt it muſt be confeſt, that having no idea of the ſubſtance of the ſoul, 'tis impoſſible for us to tell how it can admit of ſuch differences, and even contrarieties of perception without any fundamental change; and conſequently can never tell in what ſenſe perceptions are actions of that ſubſtance. The uſe, therefore, of the word, action, unaccom⯑pany'd with any meaning, inſtead of that of modification, makes no addition to our knowledge, nor is of any advantage to the doctrine of the immateriality of the ſoul.

I ADD in the ſecond place, that if it brings any advantage to that cauſe, it muſt bring an equal to the cauſe of atheiſm. For do our Theologians pretend to make a mo⯑nopoly [428] of the word, action, and may not the atheiſts likewiſe take poſſeſſion of it, and af⯑firm that plants, animals, men, &c. are nothing but particular actions of one ſimple univerſal ſubſtance, which exerts itſelf from a blind and abſolute neceſſity? This you'll ſay is utterly abſurd. I own 'tis unintel⯑ligible; but at the ſame time aſſert, ac⯑cording to the principles above-explain'd, that 'tis impoſſible to diſcover any abſurdity in the ſuppoſition, that all the various ob⯑jects in nature are actions of one ſimple ſub⯑ſtance, which abſurdity will not be appli⯑cable to a like ſuppoſition concerning im⯑preſſions and ideas.

FROM theſe hypotheſes concerning the ſubſtance and local conjunction of our per⯑ceptions, we may paſs to another, which is more intelligible than the former, and more important than the latter, viz. concerning the cauſe of our perceptions. Matter and mo⯑tion, 'tis commonly ſaid in the ſchools, however vary'd, are ſtill matter and motion, and produce only a difference in the po⯑ſition and ſituation of objects. Divide a body as often as you pleaſe, 'tis ſtill body. Place it in any figure, nothing ever reſults but figure, or the relation of parts. Move it in any manner, you ſtill find motion or [429] a change of relation. 'Tis abſurd to ima⯑gine, that motion in a circle, for inſtance, ſhou'd be nothing but merely motion in a circle; while motion in another direction, as in an ellipſe, ſhou'd alſo be a paſſion or moral reflection: That the ſhocking of two globular particles ſhou'd become a ſenſation of pain, and that the meeting of two tri⯑angular ones ſhou'd afford a pleaſure. Now as theſe different ſhocks, and variations, and mixtures are the only changes, of which matter is ſuſceptible, and as theſe never af⯑ford us any idea of thought or perception, 'tis concluded to be impoſſible, that thought can ever be caus'd by matter.

FEW have been able to withſtand the ſeeming evidence of this argument; and yet nothing in the world is more eaſy than to refute it. We need only reflect on what has been prov'd at large, that we are never ſenſible of any connexion betwixt cauſes and effects, and that 'tis only by our experience of their conſtant conjunction, we can arrive at any knowledge of this re⯑lation. Now as all objects, which are not contrary, are ſuſceptible of a conſtant con⯑junction, and as no real objects are contrary; ^* I have inferr'd from theſe principles, that [430] to conſider the matter a priori, any thing may produce any thing, and that we ſhall never diſcover a reaſon, why any object may or may not be the cauſe of any other, however great, or however little the reſem⯑blance may be betwixt them. This evi⯑dently deſtroys the precedent reaſoning con⯑cerning the cauſe of thought or perception. For tho' there appear no manner of con⯑nexion betwixt motion or thought, the caſe is the ſame with all other cauſes and effects. Place one body of a pound weight on one end of a lever, and another body of the ſame weight on another end; you will never find in theſe bodies any principle of motion dependent on their diſtances from the cen⯑ter, more than of thought and perception. If you pretend, therefore, to prove a priori, that ſuch a poſition of bodies can never cauſe thought; becauſe turn it which way you will, 'tis nothing but a poſition of bodies; you muſt by the ſame courſe of reaſoning conclude, that it can never produce mo⯑tion; ſince there is no more apparent con⯑nexion in the one caſe than in the other. But as this latter concluſion is contrary to evident experience, and as 'tis poſſible we may have a like experience in the opera⯑tions of the mind, and may perceive a con⯑ſtant [431] conjunction of thought and motion; you reaſon too haſtily, when from the mere con⯑ſideration of the ideas, you conclude that 'tis impoſſible motion can ever produce thought, or a different poſition of parts give riſe to a different paſſion or reflection. Nay 'tis not only poſſible we may have ſuch an experience, but 'tis certain we have it; ſince every one may perceive, that the different diſpoſitions of his body change his thoughts and ſenti⯑ments. And ſhou'd it be ſaid, that this depends on the union of ſoul and body; I wou'd anſwer, that we muſt ſeparate the queſtion concerning the ſubſtance of the mind from that concerning the cauſe of its thought; and that confining ourſelves to the latter queſtion we find by the compar⯑ing their ideas, that thought and motion are different from each other, and by experi⯑ence, that they are conſtantly united; which being all the circumſtances, that enter into the idea of cauſe and effect, when apply'd to the operations of matter, we may cer⯑tainly conclude, that motion may be, and actually is, the cauſe of thought and per⯑ception.

THERE ſeems only this dilemma left us in the preſent caſe; either to aſſert, that nothing can be the cauſe of another, but where [432] the mind can perceive the connexion in its idea of the objects: Or to maintain, that all objects, which we find conſtantly conjoin'd, are upon that account to be regarded as cauſes and effects. If we chooſe the firſt part of the dilemma, theſe are the conſe⯑quences. Firſt, We in reality affirm, that there is no ſuch thing in the univerſe as a cauſe or productive principle, not even the deity himſelf; ſince our idea of that ſu⯑preme Being is deriv'd from particular im⯑preſſions, none of which contain any effi⯑cacy, nor ſeem to have any connexion with any other exiſtence. As to what may be ſaid, that the connexion betwixt the idea of an infinitely powerful being, and that of any effect, which he wills, is ne⯑ceſſary and unavoidable; I anſwer, that we have no idea of a being endow'd with any power, much leſs of one endow'd with in⯑finite power. But if we will change ex⯑preſſions, we can only define power by con⯑nexion; and then in ſaying, that the idea of an infinitely powerful being is connected with that of every effect, which he wills, we really do no more than aſſert, that a being, whoſe volition is connected with e⯑very effect, is connected with every effect; which is an identical propoſition, and gives [433] us no inſight into the nature of this power or connexion. But, ſecondly, ſuppoſing, that the deity were the great and efficacious prin⯑ciple, which ſupplies the deficiency of all cauſes, this leads us into the groſſeſt impie⯑ties and abſurdities. For upon the ſame ac⯑count, that we have recourſe to him in na⯑tural operations, and aſſert that matter can⯑not of itſelf communicate motion, or pro⯑duce thought, viz. becauſe there is no ap⯑parent connexion betwixt theſe objects; I ſay, upon the very ſame account, we muſt acknowledge that the deity is the author of all our volitions and perceptions; ſince they have no more apparent connexion ei⯑ther with one another, or with the ſup⯑pos'd but unknown ſubſtance of the ſoul. This agency of the ſupreme Being we know to have been aſſerted by ^* ſeveral philoſo⯑phers with relation to all the actions of the mind, except volition, or rather an inconſi⯑derable part of volition; tho' 'tis eaſy to perceive, that this exception is a mere pre⯑text, to avoid the dangerous conſequences of that doctrine. If nothing be active but what has an apparent power, thought is in no caſe any more active than matter; and if this inactivity muſt make us have recourſe to a [434] deity, the ſupreme being is the real cauſe of all our actions, bad as well as good, vi⯑cious as well as virtuous.

THUS we are neceſſarily reduc'd to the other ſide of the dilemma, viz. that all ob⯑jects, which are found to be conſtantly con⯑join'd, are upon that account only to be re⯑garded as cauſes and effects. Now as all objects, which are not contrary, are ſuſcep⯑tible of a conſtant conjunction, and as no real objects are contrary; it follows, that for ought we can determine by the mere ideas, any thing may be the cauſe or effect of any thing; which evidently gives the advantage to the materialiſts above their antagoniſts.

TO PRONOUNCE, then, the final deci⯑ſion upon the whole; the queſtion concern⯑ing the ſubſtance of the ſoul is abſolutely unintelligible: All our perceptions are not ſuſceptible of a local union, either with what is extended or unextended; there being ſome of them of the one kind, and ſome of the other: And as the conſtant conjunction of objects conſtitutes the very eſſence of cauſe and effect, matter and motion may often be regarded as the cauſes of thought, as far as we have any notion of that rela⯑tion.

[435] 'TIS certainly a kind of indignity to phi⯑loſophy, whoſe ſovereign authority ought every where to be acknowledg'd, to oblige her on every occaſion to make apologies for her concluſions, and juſtify herſelf to every particular art and ſcience, which may be offended at her. This puts one in mind of a king arraign'd for high-treaſon againſt his ſubjects. There is only one occaſion, when philoſophy will think it neceſſary and even honourable to juſtify herſelf, and that is, when religion may ſeem to be in the leaſt offended; whoſe rights are as dear to her as her own, and are indeed the ſame. If any one, therefore, ſhou'd imagine that the foregoing arguments are any ways dangerous to religion, I hope the following apology will remove his apprehenſions.

THERE is no foundation for any conclu⯑ſion a priori, either concerning the opera⯑tions or duration of any object, of which 'tis poſſible for the human mind to form a conception. Any object may be imagin'd to become entirely inactive, or to be anni⯑hilated in a moment; and 'tis an evident principle, that whatever we can imagine, is poſſible. Now this is no more true of mat⯑ter, than of ſpirit; of an extended com⯑pounded ſubſtance, than of a ſimple and [436] unextended. In both caſes the metaphyſi⯑cal arguments for the immortality of the ſoul are equally inconcluſive; and in both caſes the moral arguments and thoſe deriv'd from the analogy of nature are equally ſtrong and convincing. If my philoſophy, therefore, makes no addition to the argu⯑ments for religion, I have at leaſt the ſatisfac⯑tion to think it takes nothing from them, but that every thing remains preciſely as before.

SECT. VI. Of perſonal identity.

THERE are ſome philoſophers, who imagine we are every moment inti⯑mately conſcious of what we call our SELF; that we feel its exiſtence and its continuance in exiſtence; and are certain, beyond the evidence of a demonſtration, both of its perfect identity and ſimplicity. The ſtrong⯑eſt ſenſation, the moſt violent paſſion, ſay they, inſtead of diſtracting us from this view, only fix it the more intenſely, and make us conſider their influence on ſelf either by their pain or pleaſure. To attempt a farther proof of this were to weaken its evidence; ſince no proof can be deriv'd from any fact, of [437] which we are ſo intimately conſcious; nor is there any thing, of which we can be cer⯑tain, if we doubt of this.

UNLUCKILY all theſe poſitive aſſertions are contrary to that very experience, which is pleaded for them, nor have we any idea of ſelf, after the manner it is here explain'd. For from what impreſſion cou'd this idea be deriv'd? This queſtion 'tis impoſſible to an⯑ſwer without a manifeſt contradiction and abſurdity; and yet 'tis a queſtion, which muſt neceſſarily be anſwer'd, if we wou'd have the idea of ſelf paſs for clear and in⯑telligible. It muſt be ſome one impreſſion, that gives riſe to every real idea. But ſelf or perſon is not any one impreſſion, but that to which our ſeveral impreſſions and ideas are ſuppos'd to have a reference. If any impreſſion gives riſe to the idea of ſelf, that impreſſion muſt continue invariably the ſame, thro' the whole courſe of our lives; ſince ſelf is ſuppos'd to exiſt after that man⯑ner. But there is no impreſſion conſtant and invariable. Pain and pleaſure, grief and joy, paſſions and ſenſations ſucceed each o⯑ther, and never all exiſt at the ſame time. It cannot, therefore, be from any of theſe impreſſions, or from any other, that the [438] idea of ſelf is deriv'd; and conſequently there is no ſuch idea.

BUT farther, what muſt become of all our particular perceptions upon this hypo⯑theſis? All theſe are different, and diſtin⯑guiſhable, and ſeparable from each other, and may be ſeparately conſider'd, and may exiſt ſeparately, and have no need of any thing to ſupport their exiſtence. After what man⯑ner, therefore, do they belong to ſelf; and how are they connected with it? For my part, when I enter moſt intimately into what I call myſelf, I always ſtumble on ſome par⯑ticular perception or other, of heat or cold, light or ſhade, love or hatred, pain or plea⯑ſure. I never can catch myſelf at any time without a perception, and never can obſerve any thing but the perception. When my perceptions are remov'd for any time, as by ſound ſleep; ſo long am I inſenſible of myſelf, and may truly be ſaid not to exiſt. And were all my perceptions remov'd by death, and cou'd I neither think, nor feel, nor ſee, nor love, nor hate after the diſſo⯑lution of my body, I ſhou'd be entirely an⯑nihilated, nor do I conceive what is farther requiſite to make me a perfect non-entity. If any one upon ſerious and unprejudic'd reflection, thinks he has a different notion [439] of himſelf, I muſt confeſs I can reaſon no longer with him. All I can allow him is, that he may be in the right as well as I, and that we are eſſentially different in this particular. He may, perhaps, perceive ſome⯑thing ſimple and continu'd, which he calls himſelf; tho' I am certain there is no ſuch principle in me.

BUT ſetting aſide ſome metaphyſicians of this kind, I may venture to affirm of the reſt of mankind, that they are nothing but a bundle or collection of different percep⯑tions, which ſucceed each other with an in⯑conceivable rapidity, and are in a perpetual flux and movement. Our eyes cannot turn in their ſockets without varying our per⯑ceptions. Our thought is ſtill more variable than our ſight; and all our other ſenſes and faculties contribute to this change; nor is there any ſingle power of the ſoul, which remains unalterably the ſame, perhaps for one moment. The mind is a kind of the⯑atre, where ſeveral perceptions ſucceſſively make their appearance; paſs, re-paſs, glide away, and mingle in an infinite variety of poſtures and ſituations. There is properly no ſimplicity in it at one time, nor identity in different; whatever natural propenſion we may have to imagine that ſimplicity and [440] identity. The compariſon of the theatre muſt not miſlead us. They are the ſucceſ⯑ſive perceptions only, that conſtitute the mind; nor have we the moſt diſtant notion of the place, where theſe ſcenes are repre⯑ſented, or of the materials, of which it is compos'd.

WHAT then gives us ſo great a propen⯑ſion to aſcribe an identity to theſe ſucceſſive perceptions, and to ſuppoſe ourſelves poſſeſt of an invariable and uninterrupted exiſtence thro' the whole courſe of our lives? In order to anſwer this queſtion, we muſt diſtinguiſh betwixt perſonal identity, as it regards our thought or imagination, and as it regards our paſſions or the concern we take in our⯑ſelves. The firſt is our preſent ſubject; and to explain it perfectly we muſt take the matter pretty deep, and account for that identity, which we attribute to plants and animals; there being a great analogy betwixt it, and the identity of a ſelf or perſon.

WE have a diſtinct idea of an object, that remains invariable and uninterrupted thro' a ſuppos'd variation of time; and this idea we call that of identity or ſameneſs. We have alſo a diſtinct idea of ſeveral different objects exiſting in ſucceſſion, and connected together by a cloſe relation; and this to an [441] accurate view affords as perfect a notion of diverſity, as if there was no manner of re⯑lation among the objects. But tho' theſe two ideas of identity, and a ſucceſſion of related objects be in themſelves perfectly diſ⯑tinct, and even contrary, yet 'tis certain, that in our common way of thinking they are gene⯑rally confounded with each other. That action of the imagination, by which we conſider the uninterrupted and invariable object, and that by which we reflect on the ſucceſſion of related objects, are almoſt the ſame to the feeling, nor is there much more effort of thought requir'd in the latter caſe than in the former. The relation facilitates the tran⯑ſition of the mind from one object to an⯑other, and renders its paſſage as ſmooth as if it contemplated one continu'd object. This reſemblance is the cauſe of the confuſion and miſtake, and makes us ſubſtitute the notion of identity, inſtead of that of related objects. However at one inſtant we may conſider the related ſucceſſion as variable or interrupted, we are ſure the next to aſcribe to it a perfect identity, and regard it as in⯑variable and uninterrupted. Our propenſity to this miſtake is ſo great from the reſem⯑blance above-mention'd, that we fall into it before we are aware; and tho' we inceſ⯑ſantly [442] correct ourſelves by reflection, and return to a more accurate method of think⯑ing, yet we cannot long ſuſtain our philo⯑ſophy, or take off this biaſs from the ima⯑gination. Our laſt reſource is to yield to it, and boldly aſſert that theſe different re⯑lated objects are in effect the ſame, how⯑ever interrupted and variable. In order to juſtify to ourſelves this abſurdity, we often feign ſome new and unintelligible principle, that connects the objects together, and pre⯑vents their interruption or variation. Thus we feign the continu'd exiſtence of the percep⯑tions of our ſenſes, to remove the interrup⯑tion; and run into the notion of a ſoul, and ſelf, and ſubſtance, to diſguiſe the variation. But we may farther obſerve, that where we do not give riſe to ſuch a fiction, our pro⯑penſion to confound identity with relation is ſo great, that we are apt to imagine ^* ſome⯑thing unknown and myſterious, connecting the parts, beſide their relation; and this I take to be the caſe with regard to the iden⯑tity [443] we aſcribe to plants and vegetables. And even when this does not take place, we ſtill feel a propenſity to confound theſe ideas, tho' we are not able fully to ſatisfy ourſelves in that particular, nor find any thing invariable and uninterrupted to juſtify our notion of identity.

THUS the controverſy concerning iden⯑tity is not merely a diſpute of words. For when we attribute identity, in an improper ſenſe, to variable or interrupted objects, our miſtake is not confin'd to the expreſſion, but is commonly attended with a fiction, either of ſomething invariable and uninter⯑rupted, or of ſomething myſterious and in⯑explicable, or at leaſt with a propenſity to ſuch fictions. What will ſuffice to prove this hypotheſis to the ſatisfaction of every fair enquirer, is to ſhew from daily expe⯑rience and obſervation, that the objects, which are variable or interrupted, and yet are ſuppos'd to continue the ſame, are ſuch only as conſiſt of a ſucceſſion of parts, con⯑nected together by reſemblance, contiguity, or cauſation. For as ſuch a ſucceſſion an⯑ſwers evidently to our notion of diverſity, it can only be by miſtake we aſcribe to it an identity; and as the relation of parts, which leads us into this miſtake, is really nothing [444] but a quality, which produces an aſſociation of ideas, and an eaſy tranſition of the ima⯑gination from one to another, it can only be from the reſemblance, which this act of the mind bears to that, by which we con⯑template one continu'd object, that the er⯑ror ariſes. Our chief buſineſs, then, muſt be to prove, that all objects, to which we aſcribe identity, without obſerving their in⯑variableneſs and uninterruptedneſs, are ſuch as conſiſt of a ſucceſſion of related objects.

IN order to this, ſuppoſe any maſs of matter, of which the parts are contiguous and connected, to be plac'd before us; 'tis plain we muſt attribute a perfect identity to this maſs, provided all the parts continue uninterruptedly and invariably the ſame, whatever motion or change of place we may obſerve either in the whole or in any of the parts. But ſuppoſing ſome very ſmall or inconſiderable part to be added to the maſs, or ſubſtracted from it; tho' this abſolutely deſtroys the identity of the whole, ſtrictly ſpeaking; yet as we ſeldom think ſo accurately, we ſcruple not to pronounce a maſs of matter the ſame, where we find ſo trivial an alteration. The paſſage of the thought from the object before the change to the object after it, is ſo ſmooth and eaſy, that we ſcarce perceive [445] the tranſition, and are apt to imagine, that 'tis nothing but a continu'd ſurvey of the ſame object.

THERE is a very remarkable circum⯑ſtance, that attends this experiment; which is, that tho' the change of any conſiderable part in a maſs of matter deſtroys the iden⯑tity of the whole, yet we muſt meaſure the greatneſs of the part, not abſolutely, but by its proportion to the whole. The addition or diminution of a mountain wou'd not be ſufficient to produce a diverſity in a planet; tho' the change of a very few inches wou'd be able to deſtroy the identity of ſome bo⯑dies. 'Twill be impoſſible to account for this, but by reflecting that objects operate upon the mind, and break or interrupt the continuity of its actions not according to their real greatneſs, but according to their proportion to each other: And therefore, ſince this interruption makes an object ceaſe to appear the ſame, it muſt be the unin⯑terrupted progreſs of the thought, which conſtitutes the imperfect identity.

THIS may be confirm'd by another phae⯑nomenon. A change in any conſiderable part of a body deſtroys its identity; but 'tis remarkable, that where the change is pro⯑duc'd gradually and inſenſibly we are leſs apt [446] to aſcribe to it the ſame effect. The rea⯑ſon can plainly be no other, than that the mind, in following the ſucceſſive changes of the body, feels an eaſy paſſage from the ſurveying its condition in one moment to the viewing of it in another, and at no particular time perceives any interruption in its actions. From which continu'd percep⯑tion, it aſcribes a continu'd exiſtence and identity to the object.

BUT whatever precaution we may uſe in introducing the changes gradually, and ma⯑king them proportionable to the whole, 'tis certain, that where the changes are at laſt obſerv'd to become conſiderable, we make a ſcruple of aſcribing identity to ſuch different objects. There is, however, another arti⯑fice, by which we may induce the imagina⯑tion to advance a ſtep farther; and that is, by producing a reference of the parts to each other, and a combination to ſome common end or purpoſe. A ſhip, of which a con⯑ſiderable part has been chang'd by frequent reparations, is ſtill conſider'd as the ſame; nor does the difference of the materials hin⯑der us from aſcribing an identity to it. The common end, in which the parts conſpire, is the ſame under all their variations, and affords [447] an eaſy tranſition of the imagination from one ſituation of the body to another.

BUT this is ſtill more remarkable, when we add a ſympathy of parts to their com⯑mon end, and ſuppoſe that they bear to each other, the reciprocal relation of cauſe and effect in all their actions and operations. This is the caſe with all animals and vege⯑tables; where not only the ſeveral parts have a reference to ſome general purpoſe, but alſo a mutual dependance on, and connexion with each other. The effect of ſo ſtrong a relation is, that tho' every one muſt allow, that in a very few years both vegetables and animals endure a total change, yet we ſtill attribute identity to them, while their form, ſize, and ſubſtance are entirely alter'd. An oak, that grows from a ſmall plant to a large tree, is ſtill the ſame oak; tho' there be not one particle of matter, or figure of its parts the ſame. An infant becomes a man, and is ſometimes fat, ſometimes lean, without any change in his identity.

WE may alſo conſider the two follow⯑ing phaenomena, which are remarkable in their kind. The firſt is, that tho' we com⯑monly be able to diſtinguiſh pretty exactly betwixt numerical and ſpecific identity, yet it ſometimes happens, that we confound [448] them, and in our thinking and reaſoning employ the one for the other. Thus a man, who hears a noiſe, that is frequently inter⯑rupted and renew'd, ſays, it is ſtill the ſame noiſe; tho' 'tis evident the ſounds have only a ſpecific identity or reſemblance, and there is nothing numerically the ſame, but the cauſe, which produc'd them. In like man⯑ner it may be ſaid without breach of the propriety of language, that ſuch a church, which was formerly of brick, fell to ruin, and that the pariſh rebuilt the ſame church of free-ſtone, and according to modern architecture. Here neither the form nor materials are the ſame, nor is there any thing common to the two objects, but their rela⯑tion to the inhabitants of the pariſh; and yet this alone is ſufficient to make us de⯑nominate them the ſame. But we muſt ob⯑ſerve, that in theſe caſes the firſt object is in a manner annihilated before the ſecond comes into exiſtence; by which means, we are never preſented in any one point of time with the idea of difference and multi⯑plicity; and for that reaſon are leſs ſcru⯑pulous in calling them the ſame.

SECONDLY, We may remark, that tho' in a ſucceſſion of related objects, it be in a manner requiſite, that the change of parts [449] be not ſudden nor entire, in order to pre⯑ſerve the identity, yet where the objects are in their nature changeable and incon⯑ſtant, we admit of a more ſudden tranſition, than wou'd otherwiſe be conſiſtent with that relation. Thus as the nature of a river con⯑ſiſts in the motion and change of parts; tho' in leſs than four and twenty hours theſe be totally alter'd; this hinders not the river from continuing the ſame during ſe⯑veral ages. What is natural and eſſential to any thing is, in a manner, expected; and what is expected makes leſs impreſſion, and appears of leſs moment, than what is un⯑uſual and extraordinary. A conſiderable change of the former kind ſeems really leſs to the imagination, than the moſt trivial al⯑teration of the latter; and by breaking leſs the continuity of the thought, has leſs influ⯑ence in deſtroying the identity.

WE now proceed to explain the nature of perſonal identity, which has become ſo great a queſtion in philoſophy, eſpecially of late years in England, where all the ab⯑ſtruſer ſciences are ſtudy'd with a peculiar ardour and application. And here 'tis evi⯑dent, the ſame method of reaſoning muſt be continu'd, which has ſo ſucceſsfully explain'd the identity of plants, and animals, and [450] ſhips, and houſes, and of all the compound⯑ed and changeable productions either of art or nature. The identity, which we aſcribe to the mind of man, is only a fictitious one, and of a like kind with that which we aſcribe to vegetables and animal bodies. It cannot, therefore, have a different origin, but muſt proceed from a like operation of the imagination upon like objects.

BUT leſt this argument ſhou'd not con⯑vince the reader; tho' in my opinion per⯑fectly deciſive; let him weigh the following reaſoning, which is ſtill cloſer and more immediate. 'Tis evident, that the identity, which we attribute to the human mind, however perfect we may imagine it to be, is not able to run the ſeveral different per⯑ceptions into one, and make them loſe their characters of diſtinction and difference, which are eſſential to them. 'Tis ſtill true, that every diſtinct perception, which enters into the compoſition of the mind, is a diſtinct exiſtence, and is different, and diſtinguiſha⯑ble, and ſeparable from every other percep⯑tion, either contemporary or ſucceſſive. But, as, notwithſtanding this diſtinction and ſe⯑parability, we ſuppoſe the whole train of perceptions to be united by identity, a que⯑ſtion naturally ariſes concerning this relation [451] of identity; whether it be ſomething that really binds our ſeveral perceptions together, or only aſſociates their ideas in the imagi⯑nation. That is, in other words, whether in pronouncing concerning the identity of a perſon, we obſerve ſome real bond among his perceptions, or only feel one among the ideas we form of them. This queſtion we might eaſily decide, if we wou'd re⯑collect what has been already prov'd at large, that the underſtanding never obſerves any real connexion among objects, and that even the union of cauſe and effect, when ſtrictly examin'd, reſolves itſelf into a cuſ⯑tomary aſſociation of ideas. For from thence it evidently follows, that identity is nothing really belonging to theſe different percep⯑tions, and uniting them together; but is merely a quality, which we attribute to them, becauſe of the union of their ideas in the imagination, when we reflect upon them. Now the only qualities, which can give ideas an union in the imagination, are theſe three relations above-mention'd. Theſe are the uniting principles in the ideal world, and without them every diſtinct object is ſeparable by the mind, and may be ſeparate⯑ly conſider'd, and appears not to have any more connexion with any other object, than [452] if disjoin'd by the greateſt difference and re⯑moteneſs. 'Tis, therefore, on ſome of theſe three relations of reſemblance, contiguity and cauſation, that identity depends; and as the very eſſence of theſe relations conſiſts in their producing an eaſy tranſition of ideas; it follows, that our notions of perſonal iden⯑tity, proceed entirely from the ſmooth and uninterrupted progreſs of the thought along a train of connected ideas, according to the principles above-explain'd.

THE only queſtion, therefore, which re⯑mains, is, by what relations this uninterrup⯑ted progreſs of our thought is produc'd, when we conſider the ſucceſſive exiſtence of a mind or thinking perſon. And here 'tis evident we muſt confine ourſelves to re⯑ſemblance and cauſation, and muſt drop contiguity, which has little or no influence in the preſent caſe.

TO begin with reſemblance; ſuppoſe we cou'd ſee clearly into the breaſt of another, and obſerve that ſucceſſion of perceptions, which conſtitutes his mind or thinking prin⯑ciple, and ſuppoſe that he always preſerves the memory of a conſiderable part of paſt perceptions; 'tis evident that nothing cou'd more contribute to the beſtowing a relation on this ſucceſſion amidſt all its variations. [453] For what the memory but a faculty, by which we raiſe up the images of paſt per⯑ceptions? And as an image neceſſarily re⯑ſembles its object, muſt not the frequent placing of theſe reſembling perceptions in the chain of thought, convey the imagina⯑tion more eaſily from one link to another, and make the whole ſeem like the continu⯑ance of one object? In this particular, then, the memory not only diſcovers the identity, but alſo contributes to its production, by producing the relation of reſemblance among the perceptions. The caſe is the ſame whether we conſider ourſelves or others.

As to cauſation; we may obſerve, that the true idea of the human mind, is to con⯑ſider it as a ſyſtem of different perceptions or different exiſtences, which are link'd to⯑gether by the relation of cauſe and effect, and mutually produce, deſtroy, influence, and modify each other. Our impreſſions give riſe to their correſpondent ideas; and theſe ideas in their turn produce other im⯑preſſions. One thought chaces another, and draws after it a third, by which it is ex⯑pell'd in its turn. In this reſpect, I cannot compare the ſoul more properly to any thing than to a republic or commonwealth, in which the ſeveral members are united by [454] the reciprocal ties of government and ſub⯑ordination, and give riſe to other perſons, who propagate the ſame republic in the in⯑ceſſant changes of its parts. And as the ſame individual republic may not only change its members, but alſo its laws and con⯑ſtitutions; in like manner the ſame perſon may vary his character and diſpoſition, as well as his impreſſions and ideas, without loſing his identity. Whatever changes he endures, his ſeveral parts are ſtill connect⯑ed by the relation of cauſation. And in this view our identity with regard to the paſ⯑ſions ſerves to corroborate that with regard to the imagination, by the making our diſtant perceptions influence each other, and by giv⯑ing us a preſent concern for our paſt or future pains or pleaſures.

As memory alone acquaints us with the continuance and extent of this ſucceſſion of perceptions, 'tis to be conſider'd, upon that account chiefly, as the ſource of perſonal identity. Had we no memory, we never ſhou'd have any notion of cauſation, nor conſequently of that chain of cauſes and effects, which conſtitute our ſelf or perſon. But having once acquir'd this notion of cau⯑ſation from the memory, we can extend the ſame chain of cauſes, and conſequently [455] the identity of our perſons beyond our me⯑mory, and can comprehend times, and cir⯑cumſtances, and actions, which we have entirely forgot, but ſuppoſe in general to have exiſted. For how few of our paſt ac⯑tions are there, of which we have any me⯑mory? Who can tell me, for inſtance, what were his thoughts and actions on the firſt of January 1715, the 11th of March 1719, and the 3d of Auguſt 1733? Or will he affirm, becauſe he has entirely forgot the incidents of theſe days, that the preſent ſelf is not the ſame perſon with the ſelf of that time; and by that means overturn all the moſt e⯑ſtabliſh'd notions of perſonal identity? In this view, therefore, memory does not ſo much produce as diſcover perſonal identity, by ſhewing us the relation of cauſe and ef⯑fect among our different perceptions. 'Twill be incumbent on thoſe, who affirm that me⯑mory produces entirely our perſonal identi⯑ty, to give a reaſon why we can thus extend our identity beyond our memory.

THE whole of this doctrine leads us to a concluſion, which is of great impor⯑tance in the preſent affair, viz. that all the nice and ſubtile queſtions concerning perſo⯑nal identity can never poſſibly be decided, and are to be regarded rather as grammati⯑cal [456] than as philoſophical difficulties. Iden⯑tity depends on the relations of ideas; and theſe relations produce identity, by means of that eaſy tranſition they occaſion. But as the relations, and the eaſineſs of the tranſi⯑tion may diminiſh by inſenſible degrees, we have no juſt ſtandard, by which we can decide any diſpute concerning the time, when they acquire or loſe a title to the name of identity. All the diſputes concern⯑ing the identity of connected objects are merely verbal, except ſo far as the relation of parts gives riſe to ſome fiction or imagi⯑nary principle of union, as we have already obſerv'd.

WHAT I have ſaid concerning the firſt origin and uncertainty of our notion of iden⯑tity, as apply'd to the human mind, may be extended with little or no variation to that of ſimplicity. An object, whoſe dif⯑ferent co-exiſtent parts are bound together by a cloſe relation, operates upon the ima⯑gination after much the ſame manner as one perfectly ſimple and indiviſible, and requires not a much greater ſtretch of thought in order to its conception. From this ſimila⯑rity of operation we attribute a ſimplicity to it, and feign a principle of union as the ſupport of this ſimplicity, and the center [457] of all the different parts and qualities of the object.

THUS we have finiſh'd our examination of the ſeveral ſyſtems of philoſophy, both of the intellectual and moral world; and in our miſcellaneous way of reaſoning have been led into ſeveral topics; which will either illuſtrate and confirm ſome pre⯑ceding part of this diſcourſe, or prepare the way for our following opinions. 'Tis now time to return to a more cloſe examination of our ſubject, and to proceed in the accu⯑rate anatomy of human nature, having fully explain'd the nature of our judgment and underſtanding.

SECT. VII. Concluſion of this book.

BUT before I launch out into thoſe im⯑menſe depths of philoſophy, which lie before me, I find myſelf inclin'd to ſtop a moment in my preſent ſtation, and to ponder that voyage, which I have under⯑taken, and which undoubtedly requires the utmoſt art and induſtry to be brought to a happy concluſion. Methinks I am like a man, who having ſtruck on many ſhoals, [458] and having narrowly eſcap'd ſhip-wreck in paſſing a ſmall frith, has yet the temerity to put out to ſea in the ſame leaky wea⯑ther-beaten veſſel, and even carries his am⯑bition ſo far as to think of compaſſing the globe under theſe diſadvantageous circum⯑ſtances. My memory of paſt errors and perplexities, makes me diffident for the fu⯑ture. The wretched condition, weakneſs, and diſorder of the faculties, I muſt employ in my enquiries, encreaſe my apprehen⯑ſions. And the impoſſibility of amending or correcting theſe faculties, reduces me almoſt to deſpair, and makes me reſolve to periſh on the barren rock, on which I am at preſent, rather than venture myſelf upon that boundleſs ocean, which runs out into immenſity. This ſudden view of my danger ſtrikes me with melancholy; and as 'tis uſual for that paſſion, above all others, to indulge itſelf; I cannot forbear feeding my deſpair, with all thoſe deſponding re⯑flections, which the preſent ſubject furniſhes me with in ſuch abundance.

I AM firſt affrighted and confounded with that forelorn ſolitude, in which I am plac'd in my philoſophy, and fancy myſelf ſome ſtrange uncouth monſter, who not being able to mingle and unite in ſociety, has [459] been expell'd all human commerce, and left utterly abandon'd and diſconſolate. Fain wou'd I run into the crowd for ſhelter and warmth; but cannot prevail with myſelf to mix with ſuch deformity. I call upon others to join me, in order to make a com⯑pany apart; but no one will hearken to me. Every one keeps at a diſtance, and dreads that ſtorm, which beats upon me from every ſide. I have expos'd myſelf to the enmity of all metaphyſicians, logicians, mathema⯑ticians, and even theologians; and can I wonder at the inſults I muſt ſuffer? I have declar'd my diſ-approbation of their ſyſtems; and can I be ſurpriz'd, if they ſhou'd ex⯑preſs a hatred of mine and of my perſon? When I look abroad, I foreſee on every ſide, diſpute, contradiction, anger, calumny and detraction. When I turn my eye in⯑ward, I find nothing but doubt and igno⯑rance. All the world conſpires to oppoſe and contradict me; tho' ſuch is my weak⯑neſs, that I feel all my opinions looſen and fall of themſelves, when unſupported by the approbation of others. Every ſtep I take is with heſitation, and every new reflection makes me dread an error and abſurdity in my reaſoning.

[460] FOR with what confidence can I venture upon ſuch bold enterprizes, when beſide thoſe numberleſs infirmities peculiar to my⯑ſelf, I find ſo many which are common to human nature? Can I be ſure, that in leav⯑ing all eſtabliſh'd opinions I am following truth; and by what criterion ſhall I diſtin⯑guiſh her, even if fortune ſhou'd at laſt guide me on her foot-ſteps? After the moſt accu⯑rate and exact of my reaſonings, I can give no reaſon why I ſhou'd aſſent to it; and feel nothing but a ſtrong propenſity to con⯑ſider objects ſtrongly in that view, under which they appear to me. Experience is a principle, which inſtructs me in the ſeveral conjunctions of objects for the paſt. Habit is another principle, which determines me to expect the ſame for the future; and both of them conſpiring to operate upon the ima⯑gination, make me form certain ideas in a more intenſe and lively manner, than others, which are not attended with the ſame ad⯑vantages. Without this quality, by which the mind enlivens ſome ideas beyond others (which ſeemingly is ſo trivial, and ſo little founded on reaſon) we cou'd never aſſent to any argument, nor carry our view be⯑yond thoſe few objects, which are preſent to our ſenſes. Nay, even to theſe ob⯑jects [461] we cou'd never attribute any exiſtence, but what was dependent on the ſenſes; and muſt comprehend them entirely in that ſuc⯑ceſſion of perceptions, which conſtitutes our ſelf or perſon. Nay farther, even with re⯑lation to that ſucceſſion, we cou'd only ad⯑mit of thoſe perceptions, which are imme⯑diately preſent to our conſciouſneſs, nor cou'd thoſe lively images, with which the memory preſents us, be ever receiv'd as true pictures of paſt perceptions. The memory, ſenſes, and underſtanding are, therefore, all of them founded on the imagination, or the vivacity of our ideas.

NO wonder a principle ſo inconſtant and fallacious ſhou'd lead us into errors, when implicitely follow'd (as it muſt be) in all its variations. 'Tis this princple, which makes us reaſon from cauſes and effects; and 'tis the ſame principle, which convinces us of the continu'd exiſtence of external objects, when abſent from the ſenſes. But tho' theſe two operations be equally natural and ne⯑ceſſary in the human mind, yet in ſome circumſtances they are ^* directly contrary, nor is it poſſible for us to reaſon juſtly and regularly from cauſes and effects, and at the ſame time believe the continu'd exiſtence of [462] matter. How then ſhall we adjuſt thoſe principles together? Which of them ſhall we prefer? Or in caſe we prefer neither of them, but ſucceſſively aſſent to both, as is uſual among philoſophers, with what con⯑fidence can we afterwards uſurp that glorious title, when we thus knowingly embrace a manifeſt contradiction?

THIS ^* contradiction wou'd be more ex⯑cuſable, were it compenſated by any degree of ſolidity and ſatisfaction in the other parts of our reaſoning. But the caſe is quite con⯑trary. When we trace up the human un⯑derſtanding to its firſt principles, we find it to lead us into ſuch ſentiments, as ſeem to turn into ridicule all our paſt pains and induſtry, and to diſcourage us from future enquiries. Nothing is more curiouſly enquir'd after by the mind of man, than the cauſes of every phaenomenon; nor are we content with knowing the immediate cauſes, but puſh on our enquiries, till we arrive at the ori⯑ginal and ultimate principle. We wou'd not willingly ſtop before we are acquainted with that energy in the cauſe, by which it operates on its effect; that tie, which con⯑nects them together; and that efficacious quality, on which the tie depends. This [463] is our aim in all our ſtudies and reflections: And how muſt we be diſappointed, when we learn, that this connexion, tie, or ener⯑gy lies merely in ourſelves, and is nothing but that determination of the mind, which is acquir'd by cuſtom, and cauſes us to make a tranſition from an object to its u⯑ſual attendant, and from the impreſſion of one to the lively idea of the other? Such a diſcovery not only cuts off all hope of ever attaining ſatisfaction, but even prevents our very wiſhes; ſince it appears, that when we ſay we deſire to know the ultimate and operating principle, as ſomething, which re⯑ſides in the external object, we either con⯑tradict ourſelves, or talk without a mean⯑ing.

THIS deficiency in our ideas is not, in⯑deed, perceiv'd in common life, nor are we ſenſible, that in the moſt uſual conjunctions of cauſe and effect we are as ignorant of the ultimate principle, which binds them toge⯑ther, as in the moſt unuſual and extraor⯑dinary. But this proceeds merely from an illuſion of the imagination; and the queſtion is, how far we ought to yield to theſe il⯑luſions. This queſtion is very difficult, and reduces us to a very dangerous dilemma, which-ever way we anſwer it. For if we [464] aſſent to every trivial ſuggeſtion of the fancy; beſide that theſe ſuggeſtions are often con⯑trary to each other; they lead us into ſuch errors, abſurdities, and obſcurities, that we muſt at laſt become aſham'd of our credu⯑lity. Nothing is more dangerous to reaſon than the flights of the imagination, and no⯑thing has been the occaſion of more miſ⯑takes among philoſophers. Men of bright fancies may in this reſpect be compar'd to thoſe angels, whom the ſcripture repreſents as covering their eyes with their wings. This has already appear'd in ſo many in⯑ſtances, that we may ſpare ourſelves the trouble of enlarging upon it any farther.

BUT on the other hand, if the conſide⯑ration of theſe inſtances makes us take a reſolution to reject all the trivial ſuggeſtions of the fancy, and adhere to the underſtand⯑ing, that is, to the general and more eſ⯑tabliſh'd properties of the imagination; even this reſolution, if ſteadily executed, wou'd be dangerous, and attended with the moſt fatal conſequences. For I have already ſhewn,^* that the underſtanding, when it acts alone, and according to its moſt general principles, entirely ſubverts itſelf, and leaves not the loweſt degree of evidence in any [465] propoſition, either in philoſophy or com⯑mon life. We ſave ourſelves from this to⯑tal ſcepticiſm only by means of that ſin⯑gular and ſeemingly trivial property of the fancy, by which we enter with difficulty into remote views of things, and are not able to accompany them with ſo ſenſible an impreſſion, as we do thoſe, which are more eaſy and natural. Shall we, then, eſ⯑tabliſh it for a general maxim, that no re⯑fin'd or elaborate reaſoning is ever to be re⯑ceiv'd? Conſider well the conſequences of ſuch a principle. By this means you cut off entirely all ſcience and philoſophy: You proceed upon one ſingular quality of the imagination, and by a parity of reaſon muſt embrace all of them: And you expreſly contradict yourſelf; ſince this maxim muſt be built on the preceding reaſoning, which will be allow'd to be ſufficiently refin'd and metaphyſical. What party, then, ſhall we chooſe among theſe difficulties? If we em⯑brace this principle, and condemn all re⯑fin'd reaſoning, we run into the moſt ma⯑nifeſt abſurdities. If we reject it in favour of theſe reaſonings, we ſubvert entirely the human underſtanding. We have, therefore, no choice left but betwixt a falſe reaſon and none at all. For my part, I know not [466] ought to be done in the preſent caſe. I can only obſerve what is commonly done; which is, that this difficulty is ſeldom or never thought of; and even where it has once been preſent to the mind, is quickly forgot, and leaves but a ſmall impreſſion behind it. Very refin'd reflections have little or no in⯑fluence upon us; and yet we do not, and cannot eſtabliſh it for a rule, that they ought not to have any influence; which implies a manifeſt contradiction.

BUT what have I here ſaid, that reflec⯑tions very refin'd and metaphyſical have lit⯑tle or no influence upon us? This opinion I can ſcarce forbear retracting, and condemn⯑ing from my preſent feeling and experience. The intenſe view of theſe manifold contra⯑dictions and imperfections in human reaſon has ſo wrought upon me, and heated my brain, that I am ready to reject all belief and reaſoning, and can look upon no opi⯑nion even as more probable or likely than another. Where am I, or what? From what cauſes do I derive my exiſtence, and to what condition ſhall I return? Whoſe fa⯑vour ſhall I court, and whoſe anger muſt I dread? What beings ſurround me? and on whom have I any influence, or who have any influence on me? I am confound⯑ed [467] with all theſe queſtions, and begin to fancy myſelf in the moſt deplorable condi⯑tion imaginable, inviron'd with the deepeſt darkneſs, and utterly depriv'd of the uſe of every member and faculty.

MOST fortunately it happens, that ſince reaſon is incapable of diſpelling theſe clouds, nature herſelf ſuffices to that purpoſe, and cures me of this philoſophical melancholy and delirium, either by relaxing this bent of mind, or by ſome avocation, and lively impreſſion of my ſenſes, which obliterate all theſe chimeras. I dine, I play a game of back-gammon, I converſe, and am merry with my friends; and when after three or four hour's amuſement, I wou'd return to theſe ſpeculations, they appear ſo cold, and ſtrain'd, and ridiculous, that I cannot find in my heart to enter into them any farther.

HERE then I find myſelf abſolutely and neceſſarily determin'd to live, and talk, and act like other people in the common affairs of life. But notwithſtanding that my na⯑tural propenſity, and the courſe of my ani⯑mal ſpirits and paſſions reduce me to this indolent belief in the general maxims of the world, I ſtill feel ſuch remains of my for⯑mer diſpoſition, that I am ready to throw all my books and papers into the fire, and re⯑ſolve [468] never more to renounce the pleaſures of life for the ſake of reaſoning and philoſophy. For thoſe are my ſentiments in that ſple⯑netic humour, which governs me at preſent. I may, nay I muſt yield to the current of nature, in ſubmitting to my ſenſes and under⯑ſtanding; and in this blind ſubmiſſion I ſhew moſt perfectly my ſceptical diſpoſition and principles. But does it follow, that I muſt ſtrive againſt the current of nature, which leads me to indolence and pleaſure; that I muſt ſeclude myſelf, in ſome meaſure, from the commerce and ſociety of men, which is ſo agreeable; and that I muſt torture my brain with ſubtilities and ſophiſtries, at the very time that I cannot ſatisfy myſelf con⯑cerning the reaſonableneſs of ſo painful an application, nor have any tolerable proſpect of arriving by its means at truth and cer⯑tainty. Under what obligation do I lie of making ſuch an abuſe of time? And to what end can it ſerve either for the ſervice of mankind, or for my own private intereſt? No: If I muſt be a fool, as all thoſe who reaſon or believe any thing certainly are, my follies ſhall at leaſt be natural and agree⯑able. Where I ſtrive againſt my inclina⯑tion, I ſhall have a good reaſon for my reſiſtance; and will no more be led a wan⯑dering [469] into ſuch dreary ſolitudes, and rough paſſages, as I have hitherto met with.

THESE are the ſentiments of my ſpleen and indolence; and indeed I muſt confeſs, that philoſophy has nothing to oppoſe to them, and expects a victory more from the returns of a ſerious good-humour'd diſ⯑poſition, than from the force of reaſon and conviction. In all the incidents of life we ought ſtill to preſerve our ſcepticiſm. If we believe, that fire warms, or water re⯑freſhes, 'tis only becauſe it coſts us too much pains to think otherwiſe. Nay if we are philoſophers, it ought only to be upon ſcepti⯑cal principles, and from an inclination, which we feel to the employing ourſelves after that manner. Where reaſon is lively, and mixes itſelf with ſome propenſity, it ought to be aſſented to. Where it does not, it never can have any title to operate upon us.

AT the time, therefore, that I am tir'd with amuſement and company, and have indulg'd a reverie in my chamber, or in a ſolitary walk by a river-ſide, I feel my mind all collected within itſelf, and am naturally inclin'd to carry my view into all thoſe ſubjects, about which I have met with ſo many diſputes in the courſe of my reading and converſation. I cannot forbear having [470] a curioſity to be acquainted with the prin⯑ciples of moral good and evil, the nature and foundation of government, and the cauſe of thoſe ſeveral paſſions and inclinations, which actuate and govern me. I am un⯑eaſy to think I approve of one object, and diſapprove of another; call one thing beau⯑tiful, and another deform'd; decide con⯑cerning truth and falſhood, reaſon and folly, without knowing upon what principles I proceed. I am concern'd for the condition of the learned world, which lies under ſuch a deplorable ignorance in all theſe particulars. I feel an ambition to ariſe in me of contri⯑buting to the inſtruction of mankind, and of acquiring a name by my inventions and diſcoveries. Theſe ſentiments ſpring up na⯑turally in my preſent diſpoſition; and ſhou'd I endeavour to baniſh them, by attaching myſelf to any other buſineſs or diverſion, I feel I ſhou'd be a loſer in point of plea⯑ſure; and this is the origin of my philo⯑ſophy.

BUT even ſuppoſe this curioſity and am⯑bition ſhou'd not tranſport me into ſpecu⯑lations without the ſphere of common life, it wou'd neceſſarily happen, that from my very weakneſs I muſt be led into ſuch en⯑quiries. 'Tis certain, that ſuperſtition is [471] much more bold in its ſyſtems and hypo⯑theſes than philoſophy; and while the latter contents itſelf with aſſigning new cauſes and principles to the phaenomena, which appear in the viſible world, the former opens a world of its own, and preſents us with ſcenes, and beings, and objects, which are altogether new. Since therefore 'tis al⯑moſt impoſſible for the mind of man to reſt, like thoſe of beaſts, in that narrow circle of objects, which are the ſubject of daily con⯑verſation and action, we ought only to de⯑liberate concerning the choice of our guide, and ought to prefer that which is ſafeſt and moſt agreeable. And in this repect I make bold to recommend philoſophy, and ſhall not ſcruple to give it the preference to ſuperſtition of every kind or denomination. For as ſuperſtition ariſes naturally and eaſily from the popular opinions of mankind, it ſeizes more ſtrongly on the mind, and is often able to diſturb us in the conduct of our lives and actions. Philoſophy on the contrary, if juſt, can preſent us only with mild and moderate ſentiments; and if falſe and extravagant, its opinions are merely the objects of a cold and general ſpeculation, and ſeldom go ſo far as to interrupt the courſe of our natural propenſities. The CYNICS [472] are an extraordinary inſtance of philoſophers, who from reaſonings purely philoſophical ran into as great extravagancies of conduct as any Monk or Derviſe that ever was in the world. Generally ſpeaking, the errors in religion are dangerous; thoſe in philo⯑ſophy only ridiculous.

I AM ſenſible, that theſe two caſes of the ſtrength and weakneſs of the mind will not comprehend all mankind, and that there are in England, in particular, many honeſt gentlemen, who being always employ'd in their domeſtic affairs, or amuſing themſelves in common recreations, have carried their thoughts very little beyond thoſe objects, which are every day expos'd to their ſenſes. And indeed, of ſuch as theſe I pretend not to make philoſophers, nor do I expect them either to be aſſociates in theſe reſearches or auditors of theſe diſcoveries. They do well to keep themſelves in their preſent ſi⯑tuation; and inſtead of refining them into philoſophers, I wiſh we cou'd communi⯑cate to our founders of ſyſtems, a ſhare of this groſs earthy mixture, as an ingredient, which they commonly ſtand much in need of, and which wou'd ſerve to temper thoſe fiery particles, of which they are compos'd. While a warm imagination is allow'd to en⯑ter [473] into philoſophy, and hypotheſes embrac'd merely for being ſpecious and agreeable, we can never have any ſteady principles, nor any ſentiments, which will ſuit with common practice and experience. But were theſe hypotheſes once remov'd, we might hope to eſtabliſh a ſyſtem or ſet of opinions, which if not true (for that, perhaps, is too much to be hop'd for) might at leaſt be ſatiſ⯑factory to the human mind, and might ſtand the teſt of the moſt critical examination. Nor ſhou'd we deſpair of attaining this end, becauſe of the many chimerical ſyſtems, which have ſucceſſively ariſen and decay'd away among men, wou'd we conſider the ſhortneſs of that period, wherein theſe queſtions have been the ſubjects of enquiry and reaſoning. Two thouſand years with ſuch long inter⯑ruptions, and under ſuch mighty diſcou⯑ragements are a ſmall ſpace of time to give any tolerable perfection to the ſciences; and perhaps we are ſtill in too early an age of the world to diſcoyer any princi⯑ples, which will bear the examination of the lateſt poſterity. For my part, my only hope is, that I may contribute a little to the advancement of knowledge, by giving in ſome particulars a different turn to the ſpeculations of philoſophers, and pointing [474] out to them more diſtinctly thoſe ſubjects, where alone they can expect aſſurance and conviction. Human Nature is the only ſci⯑ence of man; and yet has been hitherto the moſt neglected. 'Twill be ſufficient for me, if I can bring it a little more into faſhion; and the hope of this ſerves to com⯑poſe my temper from that ſpleen, and in⯑vigorate it from that indolence, which ſome⯑times prevail upon me. If the reader finds himſelf in the ſame eaſy diſpoſition, let him follow me in my future ſpeculations. If not, let him follow his inclination, and wait the returns of application and good hu⯑mour. The conduct of a man, who ſtu⯑dies philoſophy in this careleſs manner, is more truly ſceptical than that of one, who feeling in himſelf an inclination to it, is yet ſo over-whelm'd with doubts and ſcru⯑ples, as totally to reject it. A true ſceptic will be diffident of his philoſophical doubts, as well as of his philoſophical conviction; and will never refuſe any innocent ſatisfac⯑tion, which offers itſelf, upon account of either of them.

NOR is it only proper we ſhou'd in ge⯑neral indulge our inclination in the moſt elaborate philoſophical reſearches, notwith⯑ſtanding our ſceptical principles, but alſo [475] that we ſhou'd yield to that propenſity, which inclines us to be poſitive and certain in particular points, according to the light, in which we ſurvey them in any particu⯑lar inſtant. 'Tis eaſier to forbear all exa⯑mination and enquiry, than to check our⯑ſelves in ſo natural a propenſity, and guard againſt that aſſurance, which always ariſes from an exact and full ſurvey of an object. On ſuch an occaſion we are apt not only to forget our ſcepticiſm, but even our mo⯑deſty too; and make uſe of ſuch terms as theſe, 'tis evident, 'tis certain, 'tis undeniable; which a due deference to the public ought, perhaps, to prevent. I may have fallen in⯑to this fault after the example of others; but I here enter a caveat againſt any ob⯑jections, which may be offer'd on that head; and declare that ſuch expreſſions were extorted from me by the preſent view of the object, and imply no dogmatical ſpirit, nor conceited idea of my own judgment, which are ſentiments that I am ſenſible can become no body, and a ſceptic ſtill leſs than any other.