A Skeptical Solution to These Doubts

34. The passion for philosophy, like that for religion, seems liable to this inconvenience, that, though it aims at the correction of our manners, and extirpation of our vices, it may only serve, by imprudent management, to foster a predominant inclination, and push the mind, with more determined resolution, towards that side which already draws too much, by the bias and propensity of the natural temper. It is certain that, while we aspire to the magnanimous firmness of the philosophic sage, and endeavour to confine our pleasures altogether within our own minds, we may, at last, render our philosophy like that of Epictetus, and other Stoics, only a more refined system of selfishness, and reason ourselves out of all virtue as well as social enjoyment. While we study with attention the vanity of human life, and turn all our thoughts towards the empty and transitory nature of riches and honours, we are, perhaps, all the while flattering our natural indolence, which, hating the bustle of the world, and drudgery of business, seeks a pretence of reason to give itself a full and uncontrolled indulgence. There is, however, one species of philosophy which seems little liable to this inconvenience, and that because it strikes in with no disorderly passion of the human mind, nor can mingle itself with any natural affection or propensity; and that is the Academic or Sceptical philosophy. The academics always talk of doubt and suspense of judgement, of danger in hasty determinations, of confining to very narrow bounds the enquiries of the understanding, and of renouncing all speculations which lie not within the limits of common life and practice. Nothing, therefore, can be more contrary than such a philosophy to the supine indolence of the mind, its rash arrogance, its lofty pretensions, and its superstitious credulity. Every passion is mortified by it, except the love of truth; and that passion never is, nor can be, carried to too high a degree. It is surprising, therefore, that this philosophy, which, in almost every instance, must be harmless and innocent, should be the subject of so much groundless reproach and obloquy. But, perhaps, the very circumstance which renders it so innocent is what chiefly exposes it to the public hatred and resentment. By flattering no irregular passion, it gains few partizans: By opposing so many vices and follies, it raises to itself abundance of enemies, who stigmatize it as libertine profane, and irreligious.

34. A passion for philosophy, like a passion for religion, seems vulnerable to a drawback. Although it aims to improve our conduct and root out our vices, it may be pursued unwisely. In that case, it may only strengthen a dominant inclination. It may push the mind more resolutely in the direction toward which our natural temperament already draws it too strongly. We may aspire to the noble firmness of the philosophical sage and try to find all our pleasures within our own minds. Yet we may end up making our philosophy like that of Epictetus and other Stoics: merely a more refined system of selfishness. We may reason ourselves out of all virtue as well as social enjoyment. We may study the pointlessness of human life and focus all our thoughts on the emptiness and fleeting nature of riches and honors. Yet perhaps, all the while, we are indulging our natural laziness. Our laziness hates the bustle of the world and the drudgery of business. It seeks a rational excuse to indulge itself fully and without restraint. There is, however, one kind of philosophy that seems hardly vulnerable to this drawback: Academic or Skeptical philosophy. That is because it does not support any unruly passion of the human mind. Nor can it combine with any natural feeling or inclination. The academics always speak of doubt and the need to suspend judgment. They warn of the danger of hasty decisions. They urge us to keep our inquiries within very narrow bounds and abandon speculation that goes beyond ordinary life and practice. Nothing, therefore, could be more contrary to the mind’s idle laziness, rash arrogance, lofty pretensions, and superstitious gullibility. This philosophy restrains every passion except the love of truth. And that passion is never carried too far, nor can it be. It is surprising, therefore, that a philosophy that must be harmless and innocent in almost every case should face so much unjustified criticism and abuse. But perhaps the very thing that makes it so innocent is chiefly responsible for the public’s hatred and resentment of it. Because it flatters no unruly passion, it wins few supporters. Because it opposes so many vices and follies, it makes many enemies. They condemn it as immoral, profane, and irreligious.

Nor need we fear that this philosophy, while it endeavours to limit our enquiries to common life, should ever undermine the reasonings of common life, and carry its doubts so far as to destroy all action, as well as speculation. Nature will always maintain her rights, and prevail in the end over any abstract reasoning whatsoever. Though we should conclude, for instance, as in the foregoing section, that, in all reasonings from experience, there is a step taken by the mind which is not supported by any argument or process of the understanding; there is no danger that these reasonings, on which almost all knowledge depends, will ever be affected by such a discovery. If the mind be not engaged by argument to make this step, it must be induced by some other principle of equal weight and authority; and that principle will preserve its influence as long as human nature remains the same. What that principle is may well be worth the pains of enquiry.

We need not fear that this philosophy will undermine everyday reasoning as it tries to limit our inquiries to everyday life. Nor need we fear that its doubts will go so far as to destroy all action and speculation. Nature will always maintain its rights and prevail in the end over any abstract reasoning. For example, we may reach the conclusion we reached in the previous section. In all reasoning from experience, the mind takes a step unsupported by any argument or process of understanding. Yet this discovery poses no danger to such reasoning, on which almost all knowledge depends. If argument does not lead the mind to take this step, some other principle of equal weight and authority must do so. That principle will retain its influence as long as human nature remains the same. It may well be worth the effort to investigate what this principle is.

35. Suppose a person, though endowed with the strongest faculties of reason and reflection, to be brought on a sudden into this world; he would, indeed, immediately observe a continual succession of objects, and one event following another; but he would not be able to discover anything farther. He would not, at first, by any reasoning, be able to reach the idea of cause and effect; since the particular powers, by which all natural operations are performed, never appear to the senses; nor is it reasonable to conclude, merely because one event, in one instance, precedes another, that therefore the one is the cause, the other the effect. Their conjunction may be arbitrary and casual. There may be no reason to infer the existence of one from the appearance of the other. And in a word, such a person, without more experience, could never employ his conjecture or reasoning concerning any matter of fact, or be assured of anything beyond what was immediately present to his memory and senses.

35. Suppose a person with the strongest powers of reason and reflection were suddenly brought into this world. The person would immediately observe a continuous succession of objects and events following one another. But the person would be unable to discover anything more. At first, no reasoning would lead the person to the idea of cause and effect. The particular powers behind all natural operations never appear to the senses. Nor is it reasonable to conclude that one event causes another merely because it precedes the other once. The connection between the events may be arbitrary and accidental. There may be no reason to infer that one event exists from the appearance of the other. In short, without more experience, such a person could never use conjecture or reasoning about any matter of fact. The person could not be certain of anything beyond what was immediately present to memory and the senses.

Suppose, again, that he has acquired more experience, and has lived so long in the world as to have observed familiar objects or events to be constantly conjoined together; what is the consequence of this experience? He immediately infers the existence of one object from the appearance of the other. Yet he has not, by all his experience, acquired any idea or knowledge of the secret power by which the one object produces the other; nor is it, by any process of reasoning, he is engaged to draw this inference. But still he finds himself determined to draw it: And though he should be convinced that his understanding has no part in the operation, he would nevertheless continue in the same course of thinking. There is some other principle which determines him to form such a conclusion.

Suppose, again, that he has gained more experience. He has lived long enough to observe that familiar objects or events are constantly found together. What follows from this experience? As soon as one object appears, he infers that the other exists. Yet all his experience has given him no idea or knowledge of the hidden power by which one object produces the other. Nor does any process of reasoning lead him to draw this inference. Still, he finds himself compelled to draw it. Even if he were convinced that his understanding plays no part in this process, he would continue to think the same way. Some other principle leads him to reach this conclusion.

36. This principle is Custom or Habit. For wherever the repetition of any particular act or operation produces a propensity to renew the same act or operation, without being impelled by any reasoning or process of the understanding, we always say, that this propensity is the effect of Custom. By employing that word, we pretend not to have given the ultimate reason of such a propensity. We only point out a principle of human nature, which is universally acknowledged, and which is well known by its effects. Perhaps we can push our enquiries no farther, or pretend to give the cause of this cause; but must rest contented with it as the ultimate principle, which we can assign, of all our conclusions from experience. It is sufficient satisfaction, that we can go so far, without repining at the narrowness of our faculties because they will carry us no farther. And it is certain we here advance a very intelligible proposition at least, if not a true one, when we assert that, after the constant conjunction of two objects—heat and flame, for instance, weight and solidity—we are determined by custom alone to expect the one from the appearance of the other. This hypothesis seems even the only one which explains the difficulty, why we draw, from a thousand instances, an inference which we are not able to draw from one instance, that is, in no respect, different from them. Reason is incapable of any such variation. The conclusions which it draws from considering one circle are the same which it would form upon surveying all the circles in the universe. But no man, having seen only one body move after being impelled by another, could infer that every other body will move after a like impulse. All inferences from experience, therefore, are effects of custom, not of reasoning⁷.

36. This principle is Custom or Habit. When repeating an action or operation creates a tendency to repeat it again, we call that tendency the effect of Custom. This happens without any reasoning or thought driving us to repeat it. By using the word “Custom,” we do not claim to have explained the ultimate reason for this tendency. We merely point to a universally recognized principle of human nature, whose effects are well known. Perhaps we can take our inquiry no further or explain the cause of custom itself. We may have to accept custom as the ultimate principle we can identify behind all our conclusions from experience. It is enough to be satisfied that we can go this far. We need not complain that our limited faculties cannot take us further. At least, we certainly make a very clear claim, even if it is not true, when we say the following. After two things have constantly appeared together, custom alone leads us to expect one when the other appears. Heat and flame are one example, weight and solidity another. This explanation seems to be the only one that resolves a difficulty. Why do we draw a conclusion from a thousand instances when we cannot draw it from one instance? That single instance is no different from the others in any respect. Reason cannot vary in this way. Its conclusions from considering one circle are the same as those it would reach from examining every circle in the universe. But no one who has seen only one body move after being struck by another could conclude that every other body will move after a similar impact. All inferences from experience, therefore, are effects of custom, not of reasoning⁷.

Custom, then, is the great guide of human life. It is that principle alone which renders our experience useful to us, and makes us expect, for the future, a similar train of events with those which have appeared in the past.

Habit, then, is the great guide of human life. Habit alone makes our experience useful. It leads us to expect events in the future to follow a pattern similar to those in the past.

Without the influence of custom, we should be entirely ignorant of every matter of fact beyond what is immediately present to the memory and senses. We should never know how to adjust means to ends, or to employ our natural powers in the production of any effect. There would be an end at once of all action, as well as of the chief part of speculation.

Without the influence of habit, we would know nothing about facts beyond what we can immediately remember or perceive. We would never know how to choose the means to achieve our goals, or use our natural abilities to produce any effect. All action would end at once, as would most of our reasoning.

37. But here it may be proper to remark, that though our conclusions from experience carry us beyond our memory and senses, and assure us of matters of fact which happened in the most distant places and most remote ages, yet some fact must always be present to the senses or memory, from which we may first proceed in drawing these conclusions. A man, who should find in a desert country the remains of pompous buildings, would conclude that the country had, in ancient times, been cultivated by civilized inhabitants; but did nothing of this nature occur to him, he could never form such an inference. We learn the events of former ages from history; but then we must peruse the volumes in which this instruction is contained, and thence carry up our inferences from one testimony to another, till we arrive at the eyewitnesses and spectators of these distant events. In a word, if we proceed not upon some fact, present to the memory or senses, our reasonings would be merely hypothetical; and however the particular links might be connected with each other, the whole chain of inferences would have nothing to support it, nor could we ever, by its means, arrive at the knowledge of any real existence. If I ask why you believe any particular matter of fact, which you relate, you must tell me some reason; and this reason will be some other fact, connected with it. But as you cannot proceed after this manner, in infinitum, you must at last terminate in some fact, which is present to your memory or senses; or must allow that your belief is entirely without foundation.

37. But it may be worth noting a point here. Our conclusions from experience go beyond what we remember or perceive. They assure us of facts from the most distant places and the most remote ages. Yet we must always start from some fact present to our senses or memory. From that starting point, we can draw our conclusions. Suppose a man found the remains of grand buildings in a deserted country. He would conclude that civilized people had cultivated the country in ancient times. But if he found nothing of this kind, he could never draw that conclusion. We learn about events of earlier ages from history. But we must read the books that tell us about them. Then we must trace our conclusions back from one account to another, until we reach those who witnessed the distant events. In short, our reasoning would be merely hypothetical unless it began with a fact present to our memory or senses. The individual links might be connected to one another. But the whole chain of conclusions would have nothing to support it. Nor could we ever use it to gain knowledge of anything that actually exists. Suppose I ask why you believe some particular fact you have reported. You must give me a reason. That reason will be some other fact connected with the one you reported. But you cannot go on this way forever. You must finally reach some fact present to your memory or senses. Otherwise, you must admit that your belief has no foundation at all.

38. What, then, is the conclusion of the whole matter? A simple one; though, it must be confessed, pretty remote from the common theories of philosophy. All belief of matter of fact or real existence is derived merely from some object, present to the memory or senses, and a customary conjunction between that and some other object. Or in other words; having found, in many instances, that any two kinds of objects—flame and heat, snow and cold—have always been conjoined together; if flame or snow be presented anew to the senses, the mind is carried by custom to expect heat or cold, and to believe that such a quality does exist, and will discover itself upon a nearer approach. This belief is the necessary result of placing the mind in such circumstances. It is an operation of the soul, when we are so situated, as unavoidable as to feel the passion of love, when we receive benefits; or hatred, when we meet with injuries. All these operations are a species of natural instincts, which no reasoning or process of the thought and understanding is able either to produce or to prevent.

38. What, then, is the conclusion of the whole matter? It is simple, though admittedly quite far from common philosophical theories. All belief in matters of fact or real existence comes solely from an object present to memory or the senses, together with a customary connection between that object and another. In other words, we have found that two kinds of objects, such as flame and heat or snow and cold, have always appeared together in many instances. If flame or snow is presented to our senses again, custom leads the mind to expect heat or cold. It also leads us to believe that the expected quality exists and will reveal itself on closer approach. This belief necessarily results when the mind is placed in such circumstances. It is an operation of the soul that is unavoidable in those circumstances. It is as unavoidable as feeling love when we receive benefits or hatred when we suffer injuries. All these operations are kinds of natural instincts. No reasoning or process of thought and understanding can either produce or prevent them.

At this point, it would be very allowable for us to stop our philosophical researches. In most questions we can never make a single step farther; and in all questions we must terminate here at last, after our most restless and curious enquiries. But still our curiosity will be pardonable, perhaps commendable, if it carry us on to still farther researches, and make us examine more accurately the nature of this belief, and of the customary conjunction, whence it is derived. By this means we may meet with some explications and analogies that will give satisfaction; at least to such as love the abstract sciences, and can be entertained with speculations, which, however accurate, may still retain a degree of doubt and uncertainty. As to readers of a different taste; the remaining part of this section is not calculated for them, and the following enquiries may well be understood, though it be neglected.

At this point, we could reasonably stop our philosophical research. In most questions, we can never take a single step further. And in all questions, we must eventually stop here, even after our most restless and curious inquiries. But our curiosity would still be excusable, and perhaps even praiseworthy, if it led us to investigate further. We might examine more closely the nature of this belief and of the customary conjunction from which it comes. In this way, we may find some satisfying explanations and analogies. At least they may satisfy those who love the abstract sciences and enjoy speculation. Such speculation, however accurate, may still involve some doubt and uncertainty. The rest of this section is not intended for readers with different tastes. They may skip it and still understand the inquiries that follow.

39. Nothing is more free than the imagination of man; and though it cannot exceed that original stock of ideas furnished by the internal and external senses, it has unlimited power of mixing, compounding, separating, and dividing these ideas, in all the varieties of fiction and vision. It can feign a train of events, with all the appearance of reality, ascribe to them a particular time and place, conceive them as existent, and paint them out to itself with every circumstance, that belongs to any historical fact, which it believes with the greatest certainty. Wherein, therefore, consists the difference between such a fiction and belief? It lies not merely in any peculiar idea, which is annexed to such a conception as commands our assent, and which is wanting to every known fiction. For as the mind has authority over all its ideas, it could voluntarily annex this particular idea to any fiction, and consequently be able to believe whatever it pleases; contrary to what we find by daily experience. We can, in our conception, join the head of a man to the body of a horse; but it is not in our power to believe that such an animal has ever really existed.

39. Nothing is freer than the human imagination. It cannot go beyond the original stock of ideas supplied by our internal and external senses. But it has unlimited power to mix, combine, separate, and divide these ideas in every kind of fiction and vision. The imagination can invent a series of events that has every appearance of reality. It can place those events at a particular time and place and imagine them as real. It can picture them with every detail belonging to a historical fact that it believes with the greatest certainty. What, then, is the difference between such a fiction and belief? It does not lie merely in some special idea added to a conception we accept, but absent from every known fiction. The mind has control over all its ideas. So it could choose to add this special idea to any fiction and thus believe whatever it pleased. But daily experience shows that we cannot do this. We can imagine joining a human head to a horse’s body. But we cannot choose to believe that such an animal has ever really existed.

It follows, therefore, that the difference between fiction and belief lies in some sentiment or feeling, which is annexed to the latter, not to the former, and which depends not on the will, nor can be commanded at pleasure. It must be excited by nature, like all other sentiments; and must arise from the particular situation, in which the mind is placed at any particular juncture. Whenever any object is presented to the memory or senses, it immediately, by the force of custom, carries the imagination to conceive that object, which is usually conjoined to it; and this conception is attended with a feeling or sentiment, different from the loose reveries of the fancy. In this consists the whole nature of belief. For as there is no matter of fact which we believe so firmly that we cannot conceive the contrary, there would be no difference between the conception assented to and that which is rejected, were it not for some sentiment which distinguishes the one from the other. If I see a billiard-ball moving towards another, on a smooth table, I can easily conceive it to stop upon contact. This conception implies no contradiction; but still it feels very differently from that conception by which I represent to myself the impulse and the communication of motion from one ball to another.

It follows, therefore, that the difference between fiction and belief lies in a feeling that accompanies belief but not fiction. This feeling does not depend on our will, and we cannot produce it whenever we please. Like all other feelings, it must be awakened by nature. It must arise from the particular situation the mind is in at any given moment. Whenever an object is presented to the memory or senses, habit immediately leads the imagination to conceive of another object usually associated with it. This conception is accompanied by a feeling different from the loose daydreams of the imagination. This is the whole nature of belief. We cannot believe any matter of fact so firmly that we cannot conceive of the opposite. So the conception we accept would be no different from the one we reject, if not for some feeling that distinguishes them. Suppose I see a billiard ball moving toward another on a smooth table. I can easily imagine the moving ball stopping upon contact. This idea involves no contradiction. But it feels very different from the idea of one ball striking the other and passing its motion to it.

40. Were we to attempt a definition of this sentiment, we should, perhaps, find it a very difficult, if not an impossible task; in the same manner as if we should endeavour to define the feeling of cold or passion of anger, to a creature who never had any experience of these sentiments. Belief is the true and proper name of this feeling; and no one is ever at a loss to know the meaning of that term; because every man is every moment conscious of the sentiment represented by it. It may not, however, be improper to attempt a description of this sentiment; in hopes we may, by that means, arrive at some analogies, which may afford a more perfect explication of it. I say, then, that belief is nothing but a more vivid, lively, forcible, firm, steady conception of an object, than what the imagination alone is ever able to attain. This variety of terms, which may seem so unphilosophical, is intended only to express that act of the mind, which renders realities, or what is taken for such, more present to us than fictions, causes them to weigh more in the thought, and gives them a superior influence on the passions and imagination. Provided we agree about the thing, it is needless to dispute about the terms. The imagination has the command over all its ideas, and can join and mix and vary them, in all the ways possible. It may conceive fictitious objects with all the circumstances of place and time. It may set them, in a manner, before our eyes, in their true colours, just as they might have existed. But as it is impossible that this faculty of imagination can ever, of itself, reach belief, it is evident that belief consists not in the peculiar nature or order of ideas, but in the manner of their conception, and in their feeling to the mind. I confess, that it is impossible perfectly to explain this feeling or manner of conception. We may make use of words which express something near it. But its true and proper name, as we observed before, is belief; which is a term that every one sufficiently understands in common life. And in philosophy, we can go no farther than assert, that belief is something felt by the mind, which distinguishes the ideas of the judgement from the fictions of the imagination. It gives them more weight and influence; makes them appear of greater importance; enforces them in the mind; and renders them the governing principle of our actions. I hear at present, for instance, a person's voice, with whom I am acquainted; and the sound comes as from the next room. This impression of my senses immediately conveys my thought to the person, together with all the surrounding objects. I paint them out to myself as existing at present, with the same qualities and relations, of which I formerly knew them possessed. These ideas take faster hold of my mind than ideas of an enchanted castle. They are very different to the feeling, and have a much greater influence of every kind, either to give pleasure or pain, joy or sorrow.

40. If we tried to define this feeling, we would perhaps find it very difficult, if not impossible. It would be like trying to define the feeling of cold or anger to a creature that had never experienced either. Belief is the true and proper name for this feeling. No one is ever at a loss to understand the term, because everyone is conscious of the feeling at every moment. Still, it may be useful to try to describe this feeling. We may hope to find some analogies that offer a fuller explanation. I say, then, that belief is nothing but a more vivid, lively, forceful, firm, and steady conception of an object than imagination alone can ever achieve. This variety of terms may seem unphilosophical. They are meant only to express the act of mind that makes realities, or what we take for realities, more present to us than fictions. This act makes them count for more in our thoughts and gives them greater influence over our passions and imagination. As long as we agree about the thing itself, there is no need to dispute the terms. The imagination has control over all its ideas and can combine, mix, and vary them in every possible way. It can conceive imaginary objects with every detail of place and time. It can, in a way, set them before our eyes in their true colors, just as they might have existed. But imagination alone can never reach belief. Clearly, then, belief consists not in the particular nature or order of ideas, but in the manner in which we conceive them and how they feel to the mind. I admit that it is impossible to explain this feeling or manner of conception perfectly. We can use words that come close to expressing it. But, as we observed before, its true and proper name is belief. Everyone understands that term well enough in ordinary life. In philosophy, we can go no further than to say that belief is something the mind feels. This feeling distinguishes the ideas we judge to be true from the fictions of imagination. It gives those ideas more weight and influence. It makes them seem more important, impresses them on the mind, and makes them the governing principle of our actions. For example, I now hear the voice of someone I know, coming from the next room. This impression on my senses immediately brings that person and all the surrounding objects to mind. I picture them as existing now, with the same qualities and relations I knew them to have before. These ideas take a stronger hold on my mind than ideas of an enchanted castle. They feel very different and have a much greater influence of every kind, whether in giving pleasure or pain, joy or sorrow.

Let us, then, take in the whole compass of this doctrine, and allow, that the sentiment of belief is nothing but a conception more intense and steady than what attends the mere fictions of the imagination, and that this manner of conception arises from a customary conjunction of the object with something present to the memory or senses: I believe that it will not be difficult, upon these suppositions, to find other operations of the mind analogous to it, and to trace up these phenomena to principles still more general.

Let us consider the full scope of this doctrine. Let us accept that belief is simply an idea held more intensely and steadily than a mere fiction of the imagination. This manner of conceiving an object arises when it has become habitually associated with something present to the memory or senses. Given these assumptions, I believe it will not be difficult to find similar operations of the mind. We can also trace these phenomena to still more general principles.

41. We have already observed that nature has established connexions among particular ideas, and that no sooner one idea occurs to our thoughts than it introduces its correlative, and carries our attention towards it, by a gentle and insensible movement. These principles of connexion or association we have reduced to three, namely, Resemblance, Contiguity and Causation; which are the only bonds that unite our thoughts together, and beget that regular train of reflection or discourse, which, in a greater or less degree, takes place among all mankind. Now here arises a question, on which the solution of the present difficulty will depend. Does it happen, in all these relations, that, when one of the objects is presented to the senses or memory, the mind is not only carried to the conception of the correlative, but reaches a steadier and stronger conception of it than what otherwise it would have been able to attain? This seems to be the case with that belief which arises from the relation of cause and effect. And if the case be the same with the other relations or principles of associations, this may be established as a general law, which takes place in all the operations of the mind.

41. We have already seen that nature has established connections among particular ideas. As soon as one idea enters our thoughts, it brings a related idea to mind. Our attention moves toward the related idea gently and almost without our noticing. We have identified three principles of connection or association: Resemblance, Contiguity and Causation. These are the only bonds that unite our thoughts. They produce the orderly sequence of reflection or conversation found, to a greater or lesser degree, among all people. Now a question arises, and the solution to the present difficulty depends on it. In each of these relations, one object may be presented to the senses or the memory. When this happens, the mind is led to conceive of the related object. But does the mind also form a steadier and stronger conception of that object than it otherwise could? This seems to happen with the belief that arises from the relation of cause and effect. If the same is true of the other relations or principles of association, we may establish a general law. This law would apply to all the operations of the mind.

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 evidently enlivened 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, at least was not intended for him, it never so much as conveys our thought to him: And where it is absent, as well as the person, though the mind may pass from the thought of the one to that of the other, it feels its idea to be rather weakened than enlivened by that transition. We take a pleasure in viewing the picture of a friend, when it is set before us; but when it is removed, rather choose to consider him directly than by reflection in an image, which is equally distant and obscure.

We may therefore begin with an experiment relevant to our present purpose. When we see a picture of an absent friend, its resemblance clearly makes our idea of him more vivid. Every emotion that the idea arouses, whether joy or sorrow, also gains new force and strength. Both a relation and a present impression contribute to this effect. If the picture does not resemble our friend, or at least was not intended to represent him, it never even brings him to mind. And if both the picture and the person are absent, the mind may pass from thinking of one to thinking of the other. But the mind feels that the transition weakens rather than enlivens its idea of him. We take pleasure in looking at a picture of a friend when it is before us. But when it is removed, we prefer to think of him directly rather than as reflected in an image. For the image is equally distant and obscure.

The ceremonies of the Roman Catholic religion may be considered as instances of the same nature. The devotees of that superstition usually plead in excuse for the mummeries, with which they are upbraided, that they feel the good effect of those external motions, and postures, and actions, in enlivening their devotion and quickening their fervour, which otherwise would decay, 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 presence of these types, than it is 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 convey to those ideas to which they are related, and which they resemble. I shall only infer from these practices, and this reasoning, that the effect of resemblance in enlivening the ideas is very common; and as in every case a resemblance and a present impression must concur, we are abundantly supplied with experiments to prove the reality of the foregoing principle.

The ceremonies of the Roman Catholic religion may be considered examples of the same kind. Devotees of that superstition are often criticized for their empty rituals. They usually defend them by saying that the outward movements, postures, and actions have a good effect. These actions enliven their devotion and stir their fervor. Otherwise, their fervor would fade if it were directed entirely toward distant, immaterial objects. They say that they represent the objects of their faith through things the senses can perceive, such as images. Because these representations are immediately present, they make the objects of faith feel more present. They do this more effectively than thought and contemplation alone can. Objects perceived by the senses always have a greater influence on the imagination than any others. They readily pass this influence on to the ideas they are related to and resemble. From these practices and this reasoning, I will only infer that resemblance commonly makes ideas more vivid. In every case, a resemblance and a present impression must occur together. So we have ample examples to prove that the principle just described is real.

42. We may add force to these experiments by others of a different kind, in considering the effects of contiguity as well as of resemblance. It is certain that distance diminishes the force of every idea, and that, upon our approach to any object; though it does not discover itself to our senses; it operates upon the mind with an influence, which imitates an immediate impression. The thinking on any object readily transports the mind to what is contiguous; but it is 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; though even at that distance the reflecting on any thing in the neighbourhood of my friends or family 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 between them; that transition alone is not able to give a superior vivacity to any of the ideas, for want of some immediate impression⁸.

42. We may strengthen these experiments with others of a different kind, by considering contiguity as well as resemblance. Distance certainly weakens every idea. As we approach an object, it influences the mind in a way that resembles an immediate impression, even if we cannot perceive it with our senses. Thinking of an object readily carries the mind to something near it. But only the actual presence of an object carries the mind to something near it with greater vividness. When I am a few miles from home, whatever relates to it affects me more closely than when I am two hundred leagues away. Yet even at that distance, thinking of anything near my friends or family naturally brings an idea of them to mind. But in this case, both objects in the mind are ideas. Although the mind moves easily between them, that transition alone cannot make either idea more vivid, because there is no immediate impression⁸.

43. 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 reliques of saints and holy men, for the same reason, that they seek after types or images, in order to enliven their devotion, and give them a more intimate and strong conception of those exemplary lives, which they desire to imitate. Now it is evident, that one of the best reliques, which a devotee could procure, would be the handywork of a saint; and if his cloaths and furniture are ever to be considered in this light, it is because they were once at his disposal, and were moved and affected by him; in which respect they are to be considered as imperfect effects, and as connected with him by a shorter chain of consequences than any of those, by which we learn the reality of his existence.

43. No one can doubt that causation has the same influence as the other two relations, resemblance and contiguity. Superstitious people value the relics of saints and holy men for the same reason they seek representations or images. These enliven their devotion and give them a closer, stronger sense of the exemplary lives they wish to imitate. Clearly, one of the best relics a devotee could obtain would be something a saint made. And if a saint's clothes and furniture are ever regarded as relics, it is because the saint once used them and moved or affected them. In this respect, they can be regarded as imperfect effects of the saint's actions. They are connected to the saint by a shorter chain of consequences than any of those through which we learn that the saint actually existed.

Suppose, that the son of a friend, who had been long dead or absent, were presented to us; it is evident, that this object would instantly revive its correlative idea, and recal to our thoughts all past intimacies and familiarities, in more lively colours than they would otherwise have appeared to us. This is another phaenomenon, which seems to prove the principle above mentioned.

Suppose we are introduced to the son of a friend who has long been dead or absent. Clearly, seeing the son would instantly bring our friend to mind. It would recall all our past closeness and familiarity more vividly than we would otherwise remember them. This is another phenomenon that seems to support the principle mentioned above.

44. We may observe, that, in these phaenomena, the belief of the correlative object is always presupposed; without which the relation could have no effect. The influence of the picture supposes, that we believe our friend to have once existed. Contiguity to home can never excite our ideas of home, unless we believe that it really exists. Now I assert, that this belief, where it reaches beyond the memory or senses, is of a similar nature, and arises from similar causes, with the transition of thought and vivacity of conception here explained. When I throw a piece of dry wood into a fire, my mind is immediately carried to conceive, that it augments, not extinguishes the flame. This transition of thought from the cause to the effect proceeds not from reason. It derives its origin altogether from custom and experience. And as it first begins from an object, present to the senses, it renders the idea or conception of flame more strong and lively than any loose, floating reverie of the imagination. That idea arises immediately. The thought moves instantly towards it, and conveys to it all that force of conception, which is derived from the impression present to the senses. When a sword is levelled at my breast, does not the idea of wound and pain strike me more strongly, than when a glass of wine is presented to me, even though by accident this idea should occur after the appearance of the latter object? But what is there in this whole matter to cause such a strong conception, except only a present object and a customary transition to the idea of another object, which we have been accustomed to conjoin with the former? This is the whole operation of the mind, in all our conclusions concerning matter of fact and existence; and it is a satisfaction to find some analogies, by which it may be explained. The transition from a present object does in all cases give strength and solidity to the related idea.

44. We may observe that, in these cases, we always assume that the related object exists. Without that belief, the relation could have no effect. A picture affects us because we believe that our friend once existed. Being near home can never bring home to mind unless we believe that home really exists. Now I claim that, when belief extends beyond memory or the senses, it is similar in nature to the process just described. It also arises from similar causes: the movement of thought and the liveliness of our ideas. When I throw a piece of dry wood into a fire, I immediately think that it will increase the flame, not put it out. This movement of thought from cause to effect does not come from reason. It comes entirely from habit and experience. It begins with an object present to the senses. So it makes the idea of flame stronger and more vivid than any loose, drifting fancy of the imagination. The idea arises immediately. The mind moves instantly to it, giving it all the force that comes from the impression present to the senses. When a sword is pointed at my chest, does the idea of injury and pain not strike me more strongly? Compare this with the idea that might happen to occur to me when someone offers me a glass of wine. But what causes such a strong idea in the case of the sword? There is only an object present to the senses and a habitual movement to the idea of another object. We are accustomed to connecting the two objects. This is the whole operation of the mind in all our conclusions about matters of fact and existence. It is satisfying to find some analogies that may explain it. In all cases, the movement from a present object gives strength and solidity to the related idea.

Here, then, is a kind of pre-established harmony between the course of nature and the succession of our ideas; and though the powers and forces, by which the former is governed, be wholly unknown to us; yet our thoughts and conceptions have still, we find, gone on in the same train with the other works of nature. Custom is that principle, by which this correspondence has been effected; so necessary to the subsistence of our species, and the regulation of our conduct, in every circumstance and occurrence of human life. Had not the presence of an object, instantly excited the idea of those objects, commonly conjoined with it, all our knowledge must have been limited to the narrow sphere of our memory and senses; and we should never have been able to adjust means to ends, or employ our natural powers, either to the producing of good, or avoiding of evil. Those, who delight in the discovery and contemplation of final causes, have here ample subject to employ their wonder and admiration.

There is, then, a kind of pre-established harmony between the course of nature and the sequence of our ideas. The powers and forces that govern nature are completely unknown to us. Yet we find that our thoughts and ideas have followed the same course as the rest of nature. Habit is the principle that has brought about this correspondence. This correspondence is necessary for the survival of our species and for guiding our conduct in every situation and event in human life. Suppose the presence of an object did not immediately bring to mind the objects usually associated with it. Then all our knowledge would have been limited to the narrow range of our memory and senses. We would never have been able to choose means to achieve ends, or use our natural powers to produce good or avoid evil. Those who delight in discovering and contemplating final causes have here ample reason for wonder and admiration.

45. I shall add, for a further confirmation of the foregoing theory, that, as this operation of the mind, by which we infer like effects from like causes, and vice versa, is so essential to the subsistence of all human creatures, it is not probable, that it could be trusted to the fallacious deductions of our reason, which is slow in its operations; appears not, in any degree, during the first years of infancy; and at best is, in every age and period of human life, extremely liable to error and mistake. It is more conformable to the ordinary wisdom of nature to secure so necessary an act of the mind, by some instinct or mechanical tendency, which may be infallible in its operations, may discover itself at the first appearance of life and thought, and may be independent of all the laboured deductions of the understanding. As nature has taught us the use of our limbs, without giving us the knowledge of the muscles and nerves, by which they are actuated; so has she implanted in us an instinct, which carries forward the thought in a correspondent course to that which she has established among external objects; though we are ignorant of those powers and forces, on which this regular course and succession of objects totally depends.

45. I will add one more point in support of the theory I have just presented. We infer like effects from like causes, and vice versa. This mental process is essential to the survival of all human beings. So it is unlikely that nature would leave it to the unreliable deductions of reason. Reason works slowly and does not appear at all during the first years of infancy. At best, it is extremely prone to error at every age and stage of human life. It is more in keeping with nature's usual wisdom to secure such a necessary mental act through instinct or mechanical tendency. Such a tendency could operate infallibly, appear as soon as life and thought begin, and work independently of all the understanding's laborious deductions. Nature has taught us to use our limbs without knowing the muscles and nerves that move them. In the same way, nature has given us an instinct that leads our thoughts to follow the same course she has established among external objects. This happens even though we do not know the powers and forces on which that regular course and succession of objects entirely depends.