A Treatise of Human Nature. David Hume

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СКАЧАТЬ But though resemblance be the relation, which most readily produces a mistake in ideas, yet the others of causation and contiguity may also concur in the same influence. We might produce the figures of poets and orators, as sufficient proofs of this, were it as usual, as it is reasonable, in metaphysical subjects to draw our arguments from that quarter. But lest metaphysicians should esteem this below their dignity, I shall borrow a proof from an observation, which may be made on most of their own discourses, viz. that it is usual for men to use words for ideas, and to talk instead of thinking in their reasonings. We use words for ideas, because they are commonly so closely connected that the mind easily mistakes them. And this likewise is the reason, why we substitute the idea of a distance, which is not considered either as visible or tangible, in the room of extension, which is nothing but a composition of visible or tangible points disposed in a certain order. In causing this mistake there concur both the relations of causation and resemblance. As the first species of distance is found to be convertible into the second, it is in this respect a kind of cause; and the similarity of their manner of affecting the senses, and diminishing every quality, forms the relation of resemblance.

      After this chain of reasoning and explication of my principles, I am now prepared to answer all the objections that have been offered, whether derived from metaphysics or mechanics. The frequent disputes concerning a vacuum, or extension without matter prove not the reality of the idea, upon which the dispute turns; there being nothing more common, than to see men deceive themselves in this particular; especially when by means of any close relation, there is another idea presented, which may be the occasion of their mistake.

      We may make almost the same answer to the second objection, derived from the conjunction of the ideas of rest and annihilation. When every thing is annihilated in the chamber, and the walls continue immoveable, the chamber must be conceived much in the same manner as at present, when the air that fills it, is not an object of the senses. This annihilation leaves to the eye, that fictitious distance, which is discovered by the different parts of the organ, that are affected, and by the degrees of light and shade;—and to the feeling, that which consists in a sensation of motion in the hand, or other member of the body. In vain should we. search any farther. On whichever side we turn this subject, we shall find that these are the only impressions such an object can produce after the supposed annihilation; and it has already been remarked, that impressions can give rise to no ideas, but to such as resemble them.

      Since a body interposed betwixt two others may be supposed to be annihilated, without producing any change upon such as lie on each hand of it, it is easily conceived, how it may be created anew, and yet produce as little alteration. Now the motion of a body has much the same effect as its creation. The distant bodies are no more affected in the one case, than in the other. This suffices to satisfy the imagination, and proves there is no repugnance in such a motion. Afterwards experience comes in play to persuade us that two bodies, situated in the manner above-described, have really such a capacity of receiving body betwixt them, and that there is no obstacle to the conversion of the invisible and intangible distance into one that is visible and tangible. However natural that conversion may seem, we cannot be sure it is practicable, before we have had experience of it.

      Thus I seem to have answered the three objections above-mentioned; though at the same time I am sensible, that few will be satisfyed with these answers, but will immediately propose new objections and difficulties. It will probably be said, that my reasoning makes nothing to the matter in hands and that I explain only the manner in which objects affect the senses, without endeavouring to account for their real nature and operations. Though there be nothing visible or tangible interposed betwixt two bodies, yet we find BY EXPERIENCE, that the bodies may be placed in the same manner, with regard to the eye, and require the same motion of the hand in passing from one to the other, as if divided by something visible and tangible. This invisible and intangible distance is also found by experience to contain a capacity of receiving body, or of becoming visible and tangible. Here is the whole of my system; and in no part of it have I endeavoured to explain the cause, which separates bodies after this manner, and gives them a capacity of receiving others betwixt them, without any impulse or penetration.

      I answer this objection, by pleading guilty, and by confessing that my intention never was to penetrate into the nature of bodies, or explain the secret causes of their operations. For besides that this belongs not to my present purpose, I am afraid, that such an enterprise is beyond the reach of human understanding, and that we can never pretend to know body otherwise than by those external properties, which discover themselves to the senses. As to those who attempt any thing farther, I cannot approve of their ambition, till I see, in some one instance at least, that they have met with success. But at present I content myself with knowing perfectly the manner in which objects affect my senses, and their connections with each other, as far as experience informs me of them. This suffices for the conduct of life; and this also suffices for my philosophy, which pretends only to explain the nature and causes of our perceptions, or impressions and ideas [FN 4.].

      [FN 4. As long as we confine our speculations to the

       appearances of objects to our senses, without entering into

       disquisitions concerning their real nature and operations,

       we are safe from all difficulties, and can never be

       embarrassed by any question. Thus, if it be asked, if the

       invisible and intangible distance, interposed betwixt two

       objects, be something or nothing: It is easy to answer, that

       it is SOMETHING, VIZ. a property of the objects, which

       affect the SENSES after such a particular manner. If it be

       asked whether two objects, having such a distance betwixt

       them, touch or not: it may be answered, that this depends

       upon the definition of the word, TOUCH. If objects be said

       to touch, when there is nothing SENSIBLE interposed betwixt

       them, these objects touch: it objects be said to touch, when

       their IMAGES strike contiguous parts of the eye, and when

       the hand FEELS both objects successively, without any

       interposed motion, these objects do not touch. The

       appearances of objects to our senses are all consistent; and

       no difficulties can ever arise, but from the obscurity of

       the terms we make use of.

       If we carry our enquiry beyond the appearances of objects to

       the senses, I am afraid, that most of our conclusions will

       be full of scepticism and uncertainty. Thus if it be asked,

       whether or not the invisible and intangible distance be

       always full of body, or of something that by an improvement

       of our organs might become visible or tangible, I must

       acknowledge, that I find no very decisive arguments on

       either side; though I am inclined to the contrary opinion,

       as being more suitable to vulgar and popular notions. If THE

       NEWTONIAN philosophy be rightly understood, it will be found

       to mean no more. A vacuum is asserted: That is, bodies are

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