 FILE 32 OF A TREATUS OF HUMAN NATURE, by David Hume, vol. 1 BOOK I. PART IV. OF THE SKEPTICAL AND OTHER SYSTEMS OF PHILLOSPHY I. OF SKEPTICISM 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 control on our first judgment or belief, and must enlarge our view to comprehend a kind of history of all the instances wherein our understanding has deceived us compared with those wherein its testimony was just and true. Our reason must be considered as a kind of cause of which truth is the natural effect, but such a one as by the eruption of other causes and by the inconstancy of our mental powers may frequently be prevented. By this means all knowledge degenerates into probability, and this probability is greater or less according to our experience of the veracity or deceitfulness of our understanding and according to the simplicity or intricacy of the question. There is no algebraist nor mathematician so expert in his science as to place entire confidence in any truth immediately upon his discovery of it or regard it as anything but a mere probability. Every time he runs over his proofs his confidence increases, but still more by the approbation of his friends, and is raised to its utmost perfection by the universal ascent and applause of the learned world. Now it is evident that this gradual increase of assurance is nothing but the addition of new probabilities and is derived from the constant union of causes and effects according to past experience and observation. In accounts of any length or importance, merchants seldom trust to the infallible certainty of numbers for their security, but by the artificial structure of the accounts produce a probability beyond what is derived from the skill and experience of the accountant. For that is plainly of itself some degree of probability, though uncertain and variable according to the degrees of his experience and length of the account. 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 it is easily possible by gradually diminishing the numbers to reduce the longest series of addition to the most simple question which can be formed, to an addition of two single numbers, and upon this supposition we shall find it impracticable to shoe the precise limits of knowledge and of probability, or discover that particular number 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 other and that because they will not divide but must be either entirely present or entirely absent. Besides, if any single addition were certain, every one would be so, and consequently the whole or total sum, unless the whole can be different from all 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 probability. 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 concerning knowledge, we ought always to correct the first judgment derived from the nature of the object by another judgment derived from the nature of the understanding. It is certain a man of solid sense and long experience 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 authority even with ourselves in proportion to the degrees of our reason and experience. Even the man of the best sense and longest experience, 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 species of probability to correct and regulate the first and fix its just standard and proportion. This demonstration is subject to the control of probability. So is probability liable to a new correction by a reflex act of the mind wherein the nature of our understanding 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 derived from the weakness of that faculty which judges, and having adjusted these two together, we are obliged by our reason to add a new doubt derived 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 would closely pursue our reason we cannot avoid giving a decision. But this decision, though it should be favorable to our preceding judgment being founded only on probability, must weaken still further our first evidence, and must itself be weakened by a fourth doubt of the same kind, and so on, in infinitum, till at last there remain nothing of the original probability, however great we may suppose it to have been, and however small the diminution by every new uncertainty. No finite object can subsist under a decrease repeated in infinitum, and even the vastest quantity which can enter into human imagination must in this manner be reduced to nothing. Let our first belief be never so strong it must infallibly perish by passing through so many new examinations of which each diminishes somewhat of its force and vigor. When I reflect on the natural fallibility of my judgment, I have less confidence in my opinions than when I only consider the objects 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 require a continual diminution, and at last a total extinction of belief and evidence. Should it here be asked 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 skeptics who hold that all is uncertain and that our judgment is not in anything possessed of any measures of truth and falsehood, I should reply that this question is entirely superfluous, and that neither I nor any other person was ever sincerely and constantly of that opinion. Nature by an absolute and uncontrollable necessity has determined 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 connection 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 toward them in broad sunshine. Nature has taken the pains to refute the cavals of this total skepticism, has really disputed without an antagonist, and endeavored by arguments to establish a faculty which nature has antecedently implanted in the mind and rendered unavoidable. My intention then in displaying so carefully the arguments of that fantastic sect is only to make the reader sensible of the truth of my hypothesis, that all our reasonings concerning causes and effects are derived from nothing but custom, and that belief is more properly an act of the sensitive than of the cogitative part of our natures. I have here proved that the very same principles which make us form a decision upon any subject and correct that decision by the consideration of our genius and capacity and of the situation of our mind when we examine that subject, I say I have proved that these same principles when carried further and applied to every new reflex judgment must, by continually diminishing the original evidence at last reduce it to nothing and utterly subvert all belief and opinion. If belief therefore were a simple act of the thought without any peculiar manner of conception or the addition of a force and vivacity it must infallibly destroy itself and in every case terminate in a total suspense of judgment. But as experience will sufficiently convince anyone who thinks it worthwhile to try that though he can find no error in the foregoing arguments, 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 conception which it is impossible for mere ideas and reflections to destroy. But here perhaps it may be demanded how it happens even upon my hypothesis that these arguments above explained produce not a total suspense of judgment and after what manner the mind ever retains a degree of assurance in any subject. Whereas these new probabilities which by their repetition perpetually diminished the original evidence are founded on the very same principles whether of thought or sensation as the primary judgment it may seem unavoidable that in either case they must equally subvert it and by the opposition either of contrary thoughts or sensations reduce the mind to a total uncertainty. I suppose there is some question proposed 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 conjoined with them I feel a stronger and more forcible 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 it is sometimes just and sometimes erroneous I consider it as regulated by contrary principles or causes of which some lead to truth and some to error. And in balancing these contrary causes I diminish by a new probability the assurance of my first decision. This new probability is liable to the same diminution as the foregoing and so on in infinitum. It is therefore demanded how it happens that even after all we retain a degree of belief which is sufficient for our purpose either in philosophy or common life. I answer that after the first and second decision as the action of the mind becomes forced and unnatural and the ideas faint and obscure though the principles of judgment and the balancing of opposite causes be the same as at the very beginning yet their influence on the imagination and the vigor they add to or diminish from the thought is by no means equal where the mind reaches not its objects with easiness and facility. The same principles have not the same effect as in a more natural 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 governed 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 it will not be very difficult to find them. The present subject of metaphysics will supply us abundantly. The same argument which would have been esteemed convincing in a reasoning concerning history or politics has little or no influence in these abstruser subjects even though it be perfectly comprehended and that because there is required a study and an effort of thought in order to its being comprehended. And this effort of thought disturbs 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 flowing of the passions and sentiments. A tragic poet that would represent his heroes as very ingenious and witty in their misfortunes would never touch the passions. As the emotions of the soul prevent any subtle reasoning and reflection so these latter actions of the mind are equally prejudicial to the former. The mind as well as the body seems to be endowed with a certain precise degree of force and activity which it never employs in one action but at the expense of all the rest. This is more evidently true where the actions are of quite different natures. Since in that case the force of the mind is not only diverted but even the disposition changed so is to render us incapable of a sudden transition from one action to the other and still more of performing both at once. No wonder then the conviction which arises from a subtle reasoning diminishes in proportion to the efforts which the imagination makes to enter into the reasoning and to conceive it in all its parts. If being a lively conception 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 expeditious way which some take with the skeptics to reject at once all their arguments without inquiry or examination. If the skeptical reasonings be strong, say they, it is a proof that reason may have some force and authority. If weak they can never be sufficient to invalidate all the conclusions of our understanding. This argument is not just because the skeptical reasonings were it possible for them to exist and were they not destroyed by their subtlety would be successively both strong and weak according to the successive dispositions of the mind. Reason first appears in possession of the throne prescribing laws and imposing maxims with an absolute sway and authority. Her enemy therefore is obliged to take shelter under her protection and by making use of rational arguments to prove the fallaciousness and imbecility of reason produces in a manner a patent under her hand and seal. This patent has at first an authority proportion to the present and immediate authority of reason from which it is derived. But as it is supposed to be contradictory to reason it gradually diminishes the force of that governing power and its own at the same time, till at last they both vanish away into nothing by a regular and just diminution. The skeptical and dogmatical reasons are of the same kind, though 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. It is happy therefore that nature breaks the force of all skeptical arguments in time and keeps them from having any considerable influence on the understanding, where we too trust entirely to their self-destruction that can never take place until they have first subverted all conviction and have totally destroyed human reason. End of File 32 of a Treatise of Human Nature by David Hume, Volume 1 This LibriVox recording is in the public domain. Recording by George Yeager. Book 1, Part 4, Section 2 of Skepticism with regard to the senses. First half. Thus the skeptic still continues to reason and believe, even though he asserts that he cannot defend his reason by reason, and by the same rule he must assent to the principle concerning the existence of body, though he cannot pretend by any arguments of philosophy to maintain its veracity. Yeager has not left this to his choice, and has doubtless esteemed 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 believe in the existence of body, but it is in vain to ask whether there be body or not. That is the point which we must take for granted in all our reasonings. The subject then of our present inquiry 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 what follows. We ought to examine apart those two questions which are commonly confounded together. That is, why we attribute a continued existence to objects even when they are not present to the senses, and why we suppose them to have an existence distinct from the mind and perception. After this last head I comprehend their situation as well as relations, their external position as well as the independence of their existence and operation. These two questions concerning the continued and distinct existence of body are intimately connected together, for if the objects of our senses continue to exist even when they are not perceived, their existence is of course independent of and distinct from the perception and vice versa. If their existence be independent of the perception and distinct from it, they must continue to exist even though they be not perceived. But though the decision of the one question decides the other, yet that we may the more easily discover 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, reason, or the imagination that produces the opinion of a continued or of a distinct existence. These are the only questions that are intelligible on the present subject. For as to the notion of external existence when taken for something specially different from our perceptions, see Part 2, Section 6, we have already shown its absurdity. To begin with the senses, it is evident these faculties are incapable of giving rise to the notion of the continued 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 ceased all manner of operation. These faculties therefore, if they have any influence in the present case, must produce the opinion of a distinct, not of a continued existence, and in order to that, must present their impressions either as images and representations or as these very distinct and external existences. That our senses offer not their impressions as the images of something distinct or independent and external is evident, because they convey to us nothing but a single perception and never give us the least intimation of anything beyond. A single perception can never produce the idea of a double existence, but by some inference either of the reason or imagination. When the mind looks farther than what immediately 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. In 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 concerning 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 could not be compared by these faculties. The difficulty then is how far we are ourselves, the objects of our senses. It is certain there is no question in philosophy more abstruse than that concerning identity, and the nature of the uniting principle which constitutes a person. So far from being able by our senses merely to determine this question, we must have recourse to the most profound metaphysics to give a satisfactory answer to it, and in common life it is evident these ideas of self and person are never very fixed nor determinant. It is absurd, therefore, to imagine the senses can ever distinguish betwixt ourselves and external objects. Add to this that every impression, external and internal, passions, affections, sensations, 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 colors as impressions or perceptions. And indeed if we consider the matter a right, it is scarce possible it should be otherwise, nor is it conceivable that our senses should be more capable of deceiving us in the situation and relations than in the nature of our impressions. For since all actions and sensations of the mind are known to us by consciousness, they must necessarily appear in every particular what they are and be what they appear. Anything that enters the mind, being in reality a perception, it is impossible anything should to feeling appear different. This were to suppose that even where we are most intimately conscious we might be mistaken. But not to lose time in examining whether it is possible for our senses to deceive us and represent our perceptions as distinct from ourselves, that is as external to and independent of us. Let us consider whether they really 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 ourselves. The paper on which I write at present is beyond my hand. The table is beyond the paper. The walls of the chamber 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 inferred that no other faculty is required beside the senses to convince us of the external existence of body. To prevent this inference we need only way the three following considerations. First, that properly speaking it is 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 corporeal existence to these impressions or to their objects is an act of the mind as difficult to explain as that which we examine at present. Secondly, sounds and tastes and smells, though commonly regarded by the mind as continued independent qualities, appear not to have any existence in extension and consequently cannot appear to the senses as situated externally to the body. The reason why we ascribe a place to them shall be considered afterwards. Thirdly, even our sight informs us not of distance or outness, so to speak, immediately and without a certain reasoning and experience as is acknowledged by the most rational philosophers. As to the independency of our perceptions on ourselves, this can never be an object of the senses, but any opinion we form concerning it must be derived from experience and observation. And we shall see afterwards that our conclusions from experience are far from being favorable to the doctrine of the independency of our perceptions. Meanwhile, 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 incessant revolutions which we are conscious of in ourselves. Thus, to resume what I have said concerning the senses, they give us no notion of continued 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 represented nor as original. To offer it as represented they must present both an object and an image. To make it appear as original they must convey a falsehood, and this falsehood 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 should deceive us. We may therefore conclude with certainty that the opinion of a continued and of a distinct existence never arises from the senses. To confirm this we may observe that there are three different kinds of impressions conveyed by the senses. The first are those of the figure, bulk, motion, and solidity of bodies. The second those of colors, 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 vulgar suppose the first of these to have a distinct continued 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 it is evident that whatever may be our philosophical opinion, colors, 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 continued existence of the former qualities that when the contrary opinion is advanced by modern philosophers, people imagine they can almost refute it from their feeling and experience, and that their very senses contradict this philosophy. It is also evident that colors, sounds, etc., are originally on the same footing with the pain that arises from steel and pleasure that proceeds from a fire, and that the difference betwixt them is founded neither on perception nor reason, but on the imagination. Whereas they are confessed to be, both of them, nothing but perceptions arising from the particular configurations and motions 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 colors that we can attribute a distinct continued existence to objects without 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. It is obvious these arguments are known, but to very few, and that it is not by them that children, peasants, and the greatest part of mankind are induced to attribute objects to some impressions and deny them to others. Accordingly, we find that all the conclusions which the vulgar form on this head are directly contrary to those which are confirmed by philosophy. For philosophy informs us that everything 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 continued existence to the very things they feel or see. This sentiment then, as it is entirely unreasonable, must proceed from some other faculty 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 argument from the relation of cause and effect, which is the only one that can assure us of matter effect. Even after we distinguish our perceptions from our objects, it will appear presently that we are still incapable of reasoning from the existence of one to that of the other. So that upon the whole our reason neither does nor is it possible it ever should upon any supposition give us an assurance of the continued and distinct existence of body. That opinion must be entirely owing to the imagination, which must now be the subject of our inquiry. Since all impressions are internal and perishing existences and appear as such, the notion of their distinct and continued 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 impressions. It will therefore be easy for us to discover these qualities by a comparison of the impressions to which we attribute a distinct and continued existence with those which we regard as internal and perishing. We may observe, then, that it is neither upon account of the involuntariness of certain impressions as is commonly supposed, nor of their superior force and violence that we attribute to them a reality and continued existence which we refuse to others that are voluntary or feeble. For it is evident 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, color and sound, which we suppose to be permanent beings. The heat of a fire when moderate is supposed 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 rejected, we must search for some other hypothesis by which we may discover those peculiar qualities in our impressions which makes us attribute to them a distinct and continued existence. After a little examination we shall find that all those objects to which we attribute a continued existence have a peculiar constancy 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 appeared 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 without 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 supposed to have an external existence, and is the case with no other impressions whether gentle or violent, voluntary or involuntary. This constancy, however, is not so perfect as not to admit of very considerable exceptions. These often change their position and qualities, and after a little absence or interruption may become hardly knowable. But here it is 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 reasoning from causation and produces the opinion of their continued existence. When I return to my chamber after an hour's absence, I find not my fire in the same situation in which I left it, but then I am accustomed, in other instances, to see a like alteration produced 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 continued 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 that though those internal impressions which we regard as fleeting and perishing have also a certain coherence or regularity in their appearances, yet it is of somewhat a different nature from that which we discover in bodies. Our passions are found by experience to have a mutual connection with and dependence on each other, but on no occasion is it necessary to suppose that they have existed and operated when they were not perceived in order to preserve the same dependence and connection of which we have had experience. The case is not the same with relation to external objects. Those require a continued existence, or otherwise lose in a great measure, the regularity of their operation. I am here, sees it in my chamber with my face to the fire, and all the objects that strike my senses are contained in a few yards around me. My memory 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 advances towards me. This gives occasion to many new reflections and reasonings. First, I never have observed that this noise could proceed from anything but the motion of a door, and therefore conclude that the present phenomenon is a contradiction to all past experience, unless the door, which I remember on the other side of the chamber, be still in being. Again, I have always found that a human body was possessed 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 opening it I perceive by the handwriting and subscription to have come from a friend who says he is two hundred leagues distant. It is evident I can never account for this phenomenon 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 continued existence of posts and fairies according to my memory and observation. To consider these phenomena of the porter and letter in a certain light, they are contradictions to common experience, and may be regarded as objections to those maxims which we form concerning the connections of causes and effects. I am accustomed to hear such a sound, and see such an object in motion at the same time. I have not received in this particular instance both these perceptions. These observations are contrary unless I suppose that the door still remains and that it was opened 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 occasioned to suppose the continued 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 suitable to their particular natures and circumstances. Here then I am naturally led to regard the world as something real and durable, and as preserving its existence even when it is no longer present to my perception. But though this conclusion from the coherence of appearances may seem to be of the same nature with our reasonings concerning causes and effects as being derived 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 it will readily be allowed that since nothing is ever really present to the mind besides its own perceptions, it is not only impossible that any habit should ever be acquired otherwise than by the regular succession of these perceptions, but also that any habit should ever exceed that degree of regularity. Any degree, therefore, of regularity in our perceptions can never be a foundation for us to infer a greater degree of regularity in some objects which are not perceived, since this supposes a contradiction, that is, a habit acquired by what was never present to the mind. But it is evident that whenever we infer the continued existence of the objects of sense from their coherence and the frequency of their union, it is in order to bestow on the objects a greater regularity than what is observed in our mere perceptions. We remark a connection betwixt two kinds of objects in their past appearance to the senses, but are not able to observe this connection to be perfectly constant 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 connection, notwithstanding their apparent interruption, and that the irregular appearances are joined 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 constant repetition and connection, but must arise from the cooperation of some other principles. I have already observed in part two, section four, 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 motion by the oars carries on its course without any new impulse. This I have assigned for the reason why after considering several loose standards of equality and correcting them by each other, we proceed to imagine so correct and exact a standard of that relation as is not liable to the least error or variation. The same principle makes us easily entertain this opinion of the continued 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 continued existence and as the mind is once in the train of observing and uniformity among objects, it naturally continues till it renders the uniformity as complete as possible. The simple supposition of their continued existence suffices for this purpose and gives us a notion of a much greater regularity among objects than what they have when we look no farther than our senses. But whatever force we may ascribe to this principle, I am afraid it is too weak to support alone so vast an edifice as is that of the continued existence of all external bodies and that we must join the constancy of their appearance to the coherence in order to give a satisfactory account of that opinion. As the explication of this will lead me into a considerable compass of very profound reasoning, I think it proper in order to avoid confusion to give a short sketch or abridgment of my system and afterwards draw out all its parts in their full compass. This inference from the constancy of our perceptions, like the precedent from their coherence, gives rise to the opinion of the continued existence of body, which is prior to that of its distinct existence and produces that latter principle. When we have been accustomed to observe a constancy in certain impressions and have found that the perception of the sun or ocean, for instance, returns upon us after 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 perceptions as different, which they really are, but on the contrary consider them as individually the same, upon account of their resemblance. But as this interruption of their existence is contrary to their perfect identity and makes us regard the first impression as annihilated and the second as newly created, we find ourselves somewhat at a loss and are involved in a kind of contradiction. In order to free ourselves from this difficulty, we disguise as much as possible the interruption or rather remove it entirely by supposing that these interrupted perceptions are connected by a real existence of which we are insensible. This supposition or idea of continued existence acquires a force and vivacity from the memory of these broken impressions and from that propensity 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 propensity which this illusion gives to unite these broken appearances by a continued existence. Fourthly and lastly, explain that force and vivacity of conception which arises from the propensity. First, as to the principle of individuation, 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 expressed by the word object were no ways distinguished from that meant by itself, we really should mean nothing, nor would the proposition contain a predicate and a subject, which however are implied in this affirmation. One single object conveys the idea of unity, not that of identity. On the other hand, a multiplicity of objects can never convey this idea, however resembling they may be supposed. The mind always pronounces the one not to be the other and considers them as forming two, three, or any determinant 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 unity and number there can be no medium, no more than betwixt existence and non-existence. After one object is supposed 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 observed, in part two, section five, that time, in a strict sense, implies succession, and that when we apply its idea to any unchangeable object it is only by a fiction of the imagination by which the unchangeable object is supposed to participate of the changes of the co-existent objects and in particular of that of our perceptions. This fiction of the imagination almost universally takes place, and it is by means of it that a single object placed before us and surveyed for any time without our discovering in it any interruption or variation is able to give us a notion of identity. For when we consider any two points of this time we may place them in different lights. We may either survey them at the very same instant in which case they give us the idea of number both by themselves and by the object which must be multiplied in order to be conceived 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 properly speaking is either of them according to the view in which we take it, and this 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 betwixt 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 uninterruptedness of any object through a supposed variation 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 obliged to form the idea of multiplicity or number. End of File 33 File 34 of A Treatise of Human Nature by David Hume, Volume 1 This LibriVox recording is in the public domain. Recording by George Yeager. Book 1, Part 4, Section 2 of Skepticism with Regard to the Senses, Second Half. I now proceed to explain the second part of my system and shoe why the constancy of our perceptions makes us ascribe to them a perfect numerical identity, though there be very long intervals betwixt their appearance and they have only one of the essential qualities of identity, that is, invariableness. That I may avoid all ambiguity and confusion on this head, I shall observe that I hear account for the opinions and belief of the vulgar with regard to the existence of body, and therefore must entirely conform myself to their manner of thinking and of expressing themselves. Now we have already observed that however philosophers may distinguish betwixt the objects and perceptions of the senses which they suppose co-existent and resembling, yet this is a distinction which is not comprehended by the generality of mankind, who as they perceive only one being can never ascent to the opinion of a double existence and representation. 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 perceived represents another, which is different 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, understanding by both of them what any common man means by a hat or shoe or stone or any other impression conveyed to him by his senses. I shall be sure to give warning when I return to a more philosophical way of speaking and thinking. To enter therefore upon the question concerning the source of the error and deception with regard to identity when we attribute it to our resembling perceptions, notwithstanding their interruption, I must here recall an observation which I have already proved and explained in Part 2, Section 5. Nothing is more apt to make us mistake one idea for another than any relation betwixt them which associates them together in the imagination and makes it pass with facility from one to the other. Of all relations that of resemblance is in this respect the most efficacious and that because it not only causes an association of ideas but also of dispositions 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 observed 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 it is wholly incapable. 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 causing a similar disposition. When we fix our thought on any object and suppose it to continue the same for some time it is evident we suppose the change to lie only in the time and never exert ourselves to produce 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 possessed 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 require 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 passage of the imagination from one idea to another? This question is of the last importance. For if we can find any such objects we may certainly conclude from the foregoing principle that they are very naturally confounded with identical ones and are taken for them in most of our reasonings. But though this question be very important it is not very difficult nor doubtful. For I immediately reply that a succession of related objects places the mind in this disposition and is considered with the same smooth and uninterrupted progress of the imagination as attends the view of the same invariable object. The very nature and essence of relation is to connect our ideas with each other and upon the appearance of one to facilitate the transition to its correlative. 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 action and as the continuation of the same action is an effect of the continued view of the same object it is for this reason we attribute sameness to every succession of related objects. The thought slides along the succession with equal facility as if it considered only one object and therefore confounds 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 confine ourselves to the present subject. We find by experience that there is such a constancy 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 perfectly those which formerly struck my senses. This resemblance is observed in a thousand instances and naturally connects together our ideas of these interrupted perceptions by the strongest relation and conveys the mind with an easy transition from one to another. An easy transition or passage 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. It is therefore very natural for us to mistake the one for the other. Footnote 9 This reasoning it must be confessed is somewhat abstruse and difficult to be comprehended but it is remarkable that this very difficulty may be converted into a proof of the reasoning. We may observe that there are two relations and both of them resemblances which contribute to our mistaking the succession of our interrupted perceptions for an identical object. The first is the resemblance of the perceptions. The second is the resemblance which the act of the mind in surveying a succession of resembling objects bears to that in surveying an identical object. Now these resemblances we are at to confound with each other and it is natural we should according to this very reasoning. But let us keep them distinct and we shall find no difficulty in conceiving the precedent argument. End of footnote 9 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 another and consequently such as suppose their perceptions to be their only objects and never think of a double existence internal and external representing and represented. The very image which is present to the senses is with us the real body and it is 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 ourselves at a loss how to reconcile such opposite opinions. The smooth passage of the imagination along the ideas of the resembling perceptions makes us ascribe to them a perfect identity. The interrupted manner of their appearance makes us consider them as so many resembling but still distinct beings which appear after certain intervals. The perplexity arising from this contradiction produces a propension to unite these broken appearances by the fiction of a continued existence which is the third part of that hypothesis I propose to explain. Nothing is more certain from experience than that any contradiction either to the sentiments or passions gives a sensible uneasiness whether it proceeds from without or from within from the opposition of external objects or from the combat of internal principles. On the contrary, whatever strikes in with the natural propensities and either externally forwards their satisfaction or internally concurs with their movements is sure to give a sensible pleasure. Now there being here an opposition betwixt the notion of the identity of resembling perceptions and the interruption of their appearance the mind must be uneasy in that situation and will naturally seek relief from the uneasiness. Since the uneasiness 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 our resembling perceptions makes us ascribe 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 continued as well as an invariable existence and are by that means entirely the same. But here the interruptions in the appearance of these perceptions are so long and frequent that it is 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 interruption in the appearance of a perception implies not necessarily an interruption in its existence it will be proper to touch upon some principles which we shall have occasion to explain more fully afterwards. We may begin with observing that the difficulty in the present case is not concerning the matter of fact or whether the mind forms such a conclusion concerning the continued existence of its perceptions but only concerning the manner in which the conclusion is formed. And principles from which it is derived. It is certain that almost 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. It is also certain that this very perception or object is supposed to have a continued uninterrupted being and neither to be annihilated by our absence nor to be brought into 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 can we satisfy ourselves in supposing 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 observe that what we call a mind is nothing but a heap or collection of different perceptions united together by certain relations and supposed, though falsely, to be endowed with a perfect simplicity and identity. Now as every perception is distinguishable from another and may be considered as separately existent it evidently follows that there is no absurdity in separating any particular perception 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 answer 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 connected 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 continued 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 implies not necessarily an interruption in the existence. The supposition of the continued existence of sensible objects or perceptions involves no contradiction. We may easily indulge our inclination to that supposition. When the exact resemblance of our perceptions makes us ascribe to them an identity we may remove the seeming interruption by feigning a continued being which may fill those intervals and preserve a perfect and entire identity to our perceptions. But as we hear not only fame but believe this continued 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 proved 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 conveyed by the relation to every connected idea. The relation causes a smooth passage from the impression to the idea and even gives a propensity to that passage. The mind falls so easily from the one perception to the other that it scarce perceives the change but retains in the second a considerable share of the vivacity of the first. It is excited by the lively impression and this vivacity is conveyed to the related idea without any great diminution 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. It is evident it must still have the same effect and convey the vivacity from the impression to the idea. Now this is exactly the present case. Our memory presents us of instances of perceptions perfectly resembling each other 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 continued existence in order to justify this identity and a prediction in which the interrupted appearance of these perceptions seems necessarily to involve us. Here then we have a propensity to feign the continued existence of all sensible objects 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 continued existence of body. If sometimes we ascribe a continued existence to objects which are perfectly new to us and of whose constancy and coherence we have no experience it is because the manner 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 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. It is indeed evident that as the vulgar suppose their perceptions to be their only objects and at the same time believe the continued existence of matter we must account for the origin of the belief upon that supposition. Now upon that supposition it is 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 seduced into such an opinion only by means of the resemblance of certain perceptions since we find they are only our resembling perceptions which we have a propension to suppose the same. This propension to bestow an identity on our resembling perceptions produces the fiction of a continued existence since that fiction as well as the identity is really false as is acknowledged by all philosophers and has no other effect than to remedy the interruption of our perceptions which is the only circumstance that is contrary to their identity. In the last place this propension causes belief by means of the present impressions of the memory since without the remembrance of former sensations it is plain we never should have any belief of the continued existence 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 though we are led after this manner by the natural propensity of the imagination to ascribe a continued existence to those sensible objects or perceptions which we find to resemble each other in their interrupted appearance yet a very little reflection in philosophy is sufficient to make us perceive the fallacy of that opinion. I have already observed that there is an intimate connection betwixt those two principles of a continued and of a distinct or independent existence and that we no sooner establish the one than the other follows as a necessary consequence. It is the opinion of a continued 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 continued existence to our perceptions and is the origin of many very curious opinions which we shall here endeavor to account for. It will first be proper to observe a few of those experiments which convince us that our perceptions are not possessed of any independent existence. When we press one eye with a finger we immediately perceive all the objects to become double and one half of them to be removed from their common and natural position. But as we do not attribute a continued existence to both these perceptions and as they are both of the same nature we clearly perceive that all our perceptions are dependent on our organs and the disposition of our nerves and animal spirits. This opinion is confirmed by the seeming increase and diminution of objects according to their distance by the apparent alterations in their figure by the changes in their color and other qualities from our sickness and distempers and by an infinite number of other experiments of the same kind from all which we learn that our sensible perceptions are not possessed of any distinct or independent existence. The natural consequence of this reasoning should be that our perceptions have no more a continued 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 supposed to be interrupted and perishing and different at every different return, the latter to be uninterrupted and to preserve a continued existence and identity. But however philosophical this new system may be esteemed, I assert that it is 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 principles either of the understanding or fancy that can lead us directly to embrace this opinion of the double existence of perceptions and objects. Nor can we arrive at it but by passing through the common hypothesis of the identity and continuance of our interrupted perceptions. We're we not first persuaded that our perceptions are our only objects and continue to exist and we no longer make their appearance to the senses. We should never be led to think that our perceptions and objects are different and that our objects alone preserve a continued 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. The proposition contains two parts which we shall endeavor 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 primary 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 ascent and are the first foundation of all our conclusions. The only conclusion we can draw from the existence of one thing to that of another is by means of the relation of cause and defect which shows that there is a connection between them and that the existence of one is dependent on that of the other. The idea of this relation is derived from past experience by which we find that two beings are constantly conjoined 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 observe a conjunction or a relation of cause and defect between different perceptions but can never observe it between perceptions and objects. It is impossible therefore 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. It is no less certain that this philosophical system has no primary recommendation to the imagination and that that faculty would 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 anyone would take the pains to examine this question and would invent a system to account for the direct origin of this opinion from the imagination we should 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 anyone upon this supposition shoe-wide the fancy directly and immediately proceeds to the belief of another existence resembling these perceptions in their nature but yet continued and uninterrupted and identical and after he has done this to my satisfaction as an opinion. Meanwhile I cannot forbear concluding from the very abstractness and difficulty of the first supposition that it is an improper subject for the fancy to work upon. Whoever would explain the origin of the common opinion concerning the continued and distinct existence of body must take the mind in its common situation to proceed upon the supposition that our perceptions are our only objects and continue to exist even when they are not perceived. Though this opinion be false it is 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 natural 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 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 though directly contrary are connected together may be explained as follows the imagination naturally runs on in this train of thinking our perceptions are our only objects resembling perceptions are the same however broken or uninterrupted in their appearance this appearing interruption is contrary to the identity the interruption consequently extends not beyond the appearance and the perception or object really continues to exist even when absent from us our sensible perceptions have therefore a continued and uninterrupted existence but as a little reflection destroys this conclusion that our perceptions have a continued existence by shooing that they have a dependent one it would naturally be expected that we must altogether reject the opinion that there is such a thing in nature as a continued existence which is preserved even when it no longer appears to the senses the case however is otherwise philosophers are so far from rejecting the opinion of a continued existence upon rejecting that of the independence and continuance of our sensible perceptions that though all sects agree in the latter sentiment the former which is in a manner its necessary consequence has been peculiar to a few extravagant skeptics who after all maintain that opinion in words only and were never able to bring themselves sincerely to believe it there is a great difference betwixt such opinions as we form after a calm and profound reflection and such as we embrace by a kind of instinct or natural impulse on account of their suitableness to the mind if these opinions become contrary it is not difficult to foresee which of them will have the advantage as long as our attention is bent upon the subject the philosophical and studied principle may prevail but the moment we relax our thoughts nature will display herself and draw us back to our former opinion nay, she has sometimes such an influence that she can stop our progress even in the midst of our most profound reflections and keep us from running on with all the consequences of any philosophical opinion thus though we clearly perceive the dependence and interruption of our perceptions we stop short in our career and never upon that account reject the notion of an independent and continued existence that opinion has taken such deep root in the imagination that it is impossible ever to eradicate it nor will any strained metaphysical conviction of the dependence of our perceptions be sufficient for that purpose but though our natural and obvious principles here prevail in our studied reflections it is certain there must be some struggle and opposition in the case at least so long as these rejections retain any force or vivacity in order to set ourselves at ease in this particular we can thrive a new hypothesis which seems to comprehend both these principles of reason and imagination this hypothesis is a philosophical one of the double existence of perceptions and objects which pleases our reason in allowing that our dependent perceptions are interrupted and different and at the same time is agreeable to the imagination in attributing a continued existence to something else which we call objects this philosophical system therefore of offspring of two principles which are contrary to each other which are both at once embraced by the mind and which are unable mutually to destroy each other the imagination tells us that our resembling perceptions have a continued and uninterrupted existence and are not annihilated 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 which is conformable to the hypothesis both of reflection and fancy by ascribing these contrary qualities to different existences the interruption to perceptions and continuance to objects nature is obstinate and will not quit the field however strongly attacked by reason and at the same time reason is so clear in the point that there is no possibility of disguising her not being able to reconcile these two enemies we endeavor to set ourselves at ease as much as possible by successively granting to each whatever it demands and by feigning a double existence where each may find something that has all the conditions it desires were we fully convinced that our resembling perceptions are continued and identical and independent we should never run into this opinion of a double existence since we should find satisfaction in our first supposition and would not look beyond again where we fully convinced that our perceptions are dependent and interrupted and different we should be as little inclined to embrace the opinion of a double existence since in that case we should clearly perceive the error of our first supposition of a continued existence further it is therefore from the intermediate situation of 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 happily at last is found in the system of a double existence another advantage of this philosophical system is its similarity to the vulgar one by which means we can humor our reason for a moment when it becomes troublesome and solicitous and yet upon its least negligence or inattention can easily return to our vulgar and natural notions accordingly we find that philosophers neglect not this advantage but immediately upon leaving their closets mingle with the rest of mankind in those exploded opinions that our perceptions are our only objects and continue identically and uninterruptedly the same in all their interrupted appearances there are other particulars of this system wherein we may remark its dependence on the fancy in a very conspicuous manner of these I shall observe to following first we suppose external objects to resemble internal perceptions I have already shown that the relation of cause and effect can never afford us any just conclusion from the existence or qualities of our perceptions to the existence of external continued objects and I shall further add that even though we afford such a conclusion we should never have any reason to infer that our objects resemble our perceptions that opinion therefore is derived from nothing but the quality of the fancy above explained that it borrows all its ideas from some precedent perception we can never conceive anything but perceptions and therefore must make everything resemble them secondly as we suppose our objects in general to resemble our perceptions so we take it for granted that every particular object 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 further in the fancy by the former relation we naturally add the latter to complete the union we have a strong propensity to complete every union by joining new relations to those which we have before observed betwixt any ideas as we shall have occasion to observe presently in section 5 having thus given an account 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 premises that we ought to have an implicit faith in our senses and that this would be the conclusion I should draw from the whole of my reasoning to be ingenuous I feel myself at present of a quite contrary sentiment and am more inclined 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 suppositions can ever lead to any solid and rational system they are the coherence and constancy of our perceptions which produce the opinion of their continued existence though these qualities of perceptions have no perceivable connection with such an existence the constancy of our perceptions has the most considerable effect and yet is attended with the greatest difficulties it is a gross illusion to suppose that our resembling perceptions are numerically the same and it is this illusion which leads us into the opinion that these perceptions are uninterrupted and are still existent even when they are not present to the senses this is the case with our popular system and as to our philosophical one it is liable to the same difficulties and is over and above loaded with this absurdity 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 create a new set of perceptions to which they attribute these qualities I say a new set of perceptions for we may well suppose in general but it is impossible for us distinctly to conceive objects to be in their nature anything but exactly the same with perceptions what then can we look for from this confusion of groundless and extraordinary opinions but error and falsehood and how can we justify to ourselves any belief we repose in them this skeptical doubt both with respect to reason and the senses is a malady which can never be radically cured but must return upon us every moment however we may chase it away and sometimes may seem entirely free from it it is impossible upon any system to defend either our understanding or senses and we but expose them farther when we endeavor to justify them in that manner as the skeptical doubt arises naturally from a profound and intense reflection on those subjects it always increases the farther we carry our reflections whether in opposition or conformity to it carelessness and inattention alone 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 world and going upon that supposition I intend to examine some general systems both ancient and modern which have been proposed of both before I proceed to a more particular inquiry concerning our impressions this will not perhaps in the end be found foreign to our present purpose End of file 34