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difficulty may be removed, which might retard our progress in the proposed discussion, it will be necessary, in the first place, to explore more accurately those sources in our nature which give being to experience, and consequently to all those attainments, moral and intellectual, that are derived from it. These sources are two, sense and memory. The senses, both external and internal, are the original inlets of perception. They inform the mind of the facts, which in the present instant are situated within the sphere of their activity, and no sooner discharge their office in any particular instance than the articles of information exhibited by them are devolved on the memory. Remembrance instantly succeeds sensation, insomuch that the memory becomes the sole repository of the knowledge received from sense; knowledge which, without this repository, would be as instantaneously lost as it is gotten, and could be of no service to the mind. Our sensations would be no better than the fleeting pictures of a moving object on a camera obscura, which leave not the least vestige behind them. Memory, therefore, is the only original voucher extant of those past realities for which we had once the evidence of sense. ideas are, as it were, the prints that have been left by sensible impressions. But from these two faculties, considered in themselves, there results to us the knowledge only of individual facts, and only of such facts as either heretofore have come, or at present do come, under the notice of our senses.

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Now, in order to render this knowledge useful to us, in discovering the nature of things, and in regulating our conduct, a further process of the mind is necessary, which deserves to be carefully attended to, and may be thus illustrated. I have observed a stone fall to the ground when nothing intervened to impede its motion. This single fact produces little or no effect on the mind beyond a bare remembrance. At another time, I observe the fall of a tile, at another of an apple, and so of almost every kind of body in the like situation. Thus my senses first, and then my memory, furnish me with numerous examples, which, though different in every other particular, are similar in this, that they present a body moving downwards, till obstructed either by the ground or by some intervenient object. Hence my first notion of gravitation. For, with regard to the similar circumstances of different facts, as by the repetition such circumstances are more deeply imprinted, the mind acquires a habit of retaining them, omitting those circumstances peculiar to each wherein their differences consist. Hence, if objects of any kind, in a particular manner circumstanced, are remembered to have been usually, and still more if uniformly, succeeded by certain particular consequences, the idea of the former, in the supposed circumstance introduced into the mind, immediately associates the idea of the latter;

and if the object itself, so circumstanced, be presented to the senses, the mind instantly anticipates the appearance of the customary consequence. This holds also inversely. The retention and association above explained are called Experience. The anticipation is in effect no other than a particular conclusion from that experience. Here we may remark by the way, that though memory gives birth to experience, which results from the comparison of facts remembered, the experience or habitual association remains, when the individual facts on which it is founded are all forgotten. I know from an experience, which excludes all doubt, the power of fire in melting silver, and yet may not be able at present to recollect a particular instance in which I have seen this effect produced, or even in which I have had the fact attested by a credible witness.

Some will perhaps object that the account now given makes our experimental reasoning look like a sort of mechanism, necessarily resulting from the very constitution of the mind. I acknowledge the justness of the remark, but do not think that it ought to be regarded as an objection. It is plain that our reasoning in this way, if you please to call it so, is very early, and precedes all reflection on our faculties, and the manner of applying them. Those who attend to the progress of human nature through its different stages, and through childhood in particular, will observe that children make great acquisitions in knowledge from experience long before they attain the use of speech. The beasts also, in their sphere, improve by experience, which hath in them just the same foundations of sense and memory as in us, and hath, besides, a similar influence on their actions. It is precisely in the same manner, and with the same success, that you might train a dog, or accustom a child to expect food on your calling to him in one tone of voice, and to dread your resentment when you use another. The brutes have evidently the rudiments of this species of rationality, which extends as far in them as the immediate purposes of self-preservation require, and which, whether you call it reason or instinct, they both acquire and use in the same manner as we do. That it reaches no further in them, seems to arise from an original incapacity of classing, and (if I may use the expression) generalizing their perceptions ; an exercise which to us very quickly becomes familiar, and is what chiefly fits us for the use of language. Indeed, in the extent of this capacity, as much, perhaps, as in any thing, lies also the principal natural superiority of one man over another.

But that we may be satisfied, that to this kind of reasoning, in its earliest or simplest form, little or no reflection is necessary, let it be observed, that it is now universally admitted by opticians, that it is not purely from sight, but from sight aided by

experience, that we derive our notions of the distance of visible objects from the eye. The sensation, say they, is instantaneously followed by a conclusion or judgment founded on experience. The point is determined from the different phases of the object found, in former trials, to be connected with different distances, or from the effort that accompanies the different conformations we are obliged to give the organs of sight, in order to obtain a distinct vision of the object. Now, if this be the case, as I think hath been sufficiently evinced of late, it is manifest that this judgment is so truly instantaneous, and so perfectly the result of feeling and association, that the forming of it totally escapes our notice. Perhaps in no period. of life will you find a person, that, on the first mention of it, can be easily persuaded, that he derives this knowledge from experience. Every man will be ready to tell you, that he needs no other witnesses than his eyes, to satisfy him that objects are not in contact with his body, but are at different distances from him as well as from one another. So passive is the mind in this matter, and so rapid are the transitions which, by this ideal attraction, she is impelled to make, that she is, in a manner, unconscious of her own operations. There is some

ground to think, from the exact analogy which their organs bear to ours, that the discovery of distance from the eye is attained by brutes in the same manner as by us. As to this, however, I will not be positive. But though, in this way, the mind acquires an early perception of the most obvious and necessary truths, without which the bodily organs would be of little use; in matters less important her procedure is much slower, and more the result of voluntary application; and as the exertion is more deliberate, she is more conscious of her own activity, or, at least, remembers it longer. It is then only that in common style we honour her operation with the name of reasoning; though there is no essential difference between the two cases. It is true, indeed, that the conclusions in the first way, by which also in infancy we learn language, are commonly more to be regarded as infallible, than those effected in the second.

PART III.-The subdivisions of Moral Reasoning.

But to return to the proposed distribution of moral evidence. Under it I include these three tribes, experience, analogy, and testimony. To these I shall subjoin the consideration of a fourth, totally distinct from them all, but which appears to be a mixture of the demonstrative and the moral; or rather a particular application of the former, for ascertaining the precise force of the latter. The evidence I mean is that resulting from calculations concerning chances.

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I.-Experience.

The first of these I have named peculiarly the evidence of experience, not with philosophical propriety, but in compliance with common language, and for distinction's sake. Analogical reasoning is surely reasoning from a more indirect experience. Now, as to this first kind, our experience is either uniform or various. In the one case, provided the facts on which it is founded be sufficiently numerous, the conclusion is said to be morally certain. In the other, the conclusion, built on the greater number of instances, is said to be probable, and more or less so, according to the proportion which the instances on that side bear to those on the opposite. Thus we are perfectly assured that iron thrown into the river will sink, that deal will float; because these conclusions are built on a full and uniform experience. That in the last week of December next, it will snow in any part of Britain specified, is perhaps probable; that is, if, on inquiry or recollection, we are satisfied that this hath more frequently happened than the contrary; that some time in that month it will snow, is more probable, but not certain, because, though this conclusion is founded on experience, that experience is not uniform; lastly, that it will snow some time during winter will, I believe, on the same principles, be pronounced certain.

It was affirmed that experience, or the tendency of the mind to associate ideas under the notion of causes, effects, or adjuncts, is never contracted by one example only. This assertion, it may be thought, is contradicted by the principle on which physiologists commonly proceed, who consider one accurate experiment in support of a particular doctrine as sufficient evidence. The better to explain this phenomenon, and the further to illustrate the nature of experience, I shall make the following observations. First, whereas sense and memory are conversant only about individuals, our earliest experiences imply, or perhaps generate, the notion of a species, including all those individuals which have the most obvious and universal resemblance. From Charles, Thomas, William, we ascend to the idea of man; from Britain, France, Spain, to the idea of kingdom. As our acquaintance with nature enlarges, we discover resemblances, of a striking and important nature, between one species and another, which naturally begets the notion of a genus. From comparing men with beasts, birds, fishes, and reptiles, we perceive that they are all alike possessed of life, or a principle of sensation and action, and of an organized body, and hence acquire the idea of animal: in like manner, from comparing kingdoms with republics and aristocracies, we ob

tain the idea of nation, and thence again rise in the same track to ideas still mere comprehensive. Further, let it be remembered, that by experience we not only decide concerning the future from the past, but concerning things uncommon from things familiar which resemble them.

Now, to apply this observation: a botanist, in traversing the fields, lights on a particular plant, which appears to be of a species he is not acquainted with. The flower, he observes, is monopetalous, and the number of flowers it carries is seven. Here are two facts that occur to his observation; let us consider in what way he will be disposed to argue from them. From the first he does not hesitate to conclude, not only as probable, but as certain, that this individual, and all of the same species, invariably produce monopetalous flowers. From the second, he by no means concludes, as either certain, or even probable, that the flowers which either this plant, or others of the same species, carry at once, will always be seven. This difference, to a superficial inquirer, might seem capricious, since there appears to be one example, and but one in either case, on which the conclusion can be founded. The truth is, that it is not from this example only that he deduces these inferences. Had he never heretofore taken the smallest notice of any plant, he could not have reasoned at all from these remarks. The mind recurs instantly from the unknown to all the other known species of the same genus, and thence to all the known genera of the same order or tribe; and having experienced in the one instance a regularity in every species, genus, and tribe, which admits no exception; in the other a variety as boundless as that of season, soil, and culture, it learns hence to mark the difference.

Again, we may observe, that, on a closer acquaintance with those objects wherewith we are surrounded, we come to discover that they are mostly of a compound nature, and that not only as containing a complication of those qualities called accidents, as gravity, mobility, colour, extension, figure, solidity, which are common almost to all matter, not only as consisting of different members, but as comprehending a mixture of bodies, often very different in their nature and properties, as air, fire, water, earth, salt, oil, spirit, and the like. These, perhaps, on deeper researches, will be found to consist of materials still simpler. Moreover, as we advance in the study of nature, we daily find more reason to be convinced of her constancy in all her operations, that like causes, in like circumstances, always produce like effects, and inversely, like effects always flow from like causes. The inconstancy which appears at first in some of nature's works, a more improved experience teacheth us to account for in this manner. As most of the objects we know are of a complex nature, on a narrower scrutiny we find,

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