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purposes, and desires, which are the natural language of mankind. An infant may be put into a fright by an angry countenance, and soothed again by smiles and blandishments. A child that has a good musical ear, may be put to sleep or to dance, may be made merry or sorrowful, by the modulation of musical sounds. The principles of all the fine arts, and of what we call a fine taste, may be resolved into connections of this kind. A fine taste may be improved by reasoning and experience; but if the first principles of it were not planted in our minds by nature, it could never be acquired.

A third class of natural signs comprehends those which, tho' we never before had any notion or conception of the thing sig. nified, do suggest it, or conjure it up, as it were, by a natural kind of magic, and at once give us a conception, and create a belief of it. Our Author thewed before, that our sensations suggest to us a sentient being or mind to which they belong : a being which hath a permanent existence, although the sensations are transient and of short duration: а being which is still the fame, while its sensations, and other operations, are varied ten thousand ways : a being which hath the same relation to all that infinite variety of thoughts, purposes, actions, affections, enjoyments, and sufferings, which we are conscious of, or can remember, The conception of a mind is neither an idea of sensation nor of reflection ; for it is neither like any of our sensations, nor like any thing we are conscious of. The first conception of it, as well as the belief of it, and of the common relation it bears to all that we are conscious of, or remember, is suggested to every thinking being, we do not know how.

! The notion of hardness in bodies, continues he, as well as the belief of it, are got in a similar manner; being by an original principle of our nature annexed to that sensation which we have when we feel a hard body. And so naturally and neceffarily does the sensation convey the notion and belief of hardness, that hitherto they have been confounded by the most acute Enquiress into the principles of human nature, although they appear, upon accurate reflection, not only to be different things, but as unlike as pain is to the point of a sword.

It may be observed, that as the first class of natural signs I have mentioned, is the foundation of true philosophy, and the second, the foundation of the fine arts, or of taste; so the last is the foundation of common sense; a part of human nature which hath never been explained.

I take it for granted, that the notion of hardness, and the belief of it, is first got by means of that particular sensation, which, as far back as we can remember, does invariably suggest it; and that if we had never had such a feeling, we should ne-ver have had any notion of hardness. I think it is evident, that we cannot, by reasoning from our sensations, collect the exiftence of bodies at all, far less any of their qualities. This hath been proved by unanswerable arguments by the Bishop of Cloyne, and by the Author of the Treatise of human Nature. It appears as evident, that this connection between our sensations and the conception and belief of external existences, cannot be produced by habit, experience, education, or any principle of human nature that hath been admitted by Philosophers. At the same time it is a fact, that such sensations are invariably connected with the conception and belief of external existences. Hence, by all rules of just reasoning, we must conclude, that this connection is the effect of our constitution, and ought to

be considered as an original principle of human nature, till we . find some more general principle into which it may be resolved.'

What our Author has advanced concerning hardness, is so easily applicable, not only to its oppofite, softness, but likewise to roughness and smoothness, to figure and motion, that he faves himself the trouble of a repetition. All these, he says, by means of certain corresponding sensations of touch, are presented to the mind as real external qualities; the conception and the belief of them are invariably connected with the corresponding sensations, by an original principle of human nature. Their fensations have no name in any language; they have not only been overlooked by the vulgar, but by Philosophers; or if they have been at all taken notice of, they have been confounded with the external qualities which they suggeft.

He goes on to treat of Extension, and observes, that the notion of it is so familiar to us from infancy, and so constantly obtruded by every thing we see and feel, that we are apt to think it obvious how it comes into the mind; but upon a narrow examination, he says, we shall find it utterly inexplicable. It is true we have feelings of touch, which every moment present extension to the mind; but how they come to do so, is the question ; for those feelings do no more resemble extension, than they resemble justice or courage: nor can the existence of extended things be inferred from those feelings by any rules of reasoning; so that the feelings we have by touch, can neither explain how we get the notion, nor how we come by the belief of extended things.

What hath imposed upon Philosophers in this matter, we are told, is, that the feelings of touch, which suggest primary qualities, have no names, nor are they ever reflected upon. They pass through the mind instantaneously, and ferve only to intro

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duce the notion and belief of external things, which, by our conftitution, are connected with them. They are natural signs, and the mind immediately paftes to the thing fignified, without making the least reflection upon the fign, or observing that there was any such thing. Hence it hath always been taken for granted, thái the ideas of extension, figure, and motion, are ideas of sensation, which enter into the mind by the sense of touch, in the same manner as the sensations of sound and smell do by the ear and nole. The sensations of touch are fu connected by our conftitution with the notions of extension, figure, and motion, that Philosophers have mittaken the one for the other, and never have been able to discern, that they were not only distinct things, but altogether unlike. However, if we will reason distinctly upon this subject, we ought to give names to those feelings of touch; we must accustom ourselves to attend to thein, and to reflect upon them, that we may be able to disjoin them from, and to compare them with, the qualities fignified or suggested by them.-'The habit of doing this is not to be attained without pains and practice; and till a man hath acquired this habit, it will be impossible for him to think distinctly, or to judge right upon this subject.

Our Author proceeds to make some reflections in regard to the existence of a material world, and the systems of Philosophers concerning the senses; after which he goes on to treat of the sense of Seeing. As what he advances on this subject takes up almost two thirds of his work, we must content ourselves with laying before our Readers a general view of the feveral points which he discusses.

After some general remarks on the excellence and dignity of the faculty of seeing, he observes, that there is very little of the knowlcge acquired by sight, that may not be communicated to a man born blind. One who never saw the light, inay be learned and knowing in every science, even in Optics; and may make discoveries in every branch of philosophy. He may understand as much as another man, not only of the order, distances, and motions of the heavenly bodies, but of the nature of light; and of the laws of the reflection and refraction of its rays.

He may understand distinctly, how those law's produce the phenomena of the rain-bow, the prism, the camera obscura, the magic lanthorn, and all the powers of the microscope and telescope. This is a fact, we are told, fufficiently atteited by experience.

• In order to perceive the reason of it, continues our Author, we must distinguish the appearance that objeéts make to the eye, from the things suggested by that appearance : and again, in the visible appearance of objects, we must distinguish the appearance of colour from the appearance of extension, figure, and motion. First, then, as to the visible appearance of the figure, and motion, and extension of bodies, I conceive that a man born blind may have a distinct notion, if not of the very things, at least of something extremely like to them. May not a blind man be made to conceive, that a body moving directly from the eye, or directly towards it, may appear to be at rest? and that the same motion may appear quicker or flower, according as it is nearer to the eye or farther off, more direct or more oblique ? May he not be made to conceive, that a plain surface, in a certain position, may appear as a straight line, and vary its visible figure, as its position, or the position of the eye, is varied? That a circle seen obliquely will appear an ellipse; and a square, a rhombus or an oblong rectangle? Dr. Saunderson understood the projection of the sphere, and the commun rules of perspective; and if he did, he must have understood all that I have mentioned. If there were any doubt of Dr. Saunderson's understanding these things, I could mention my having heard him fay in conversation, that he found great difficulty in understanding Dr. Halley's demonstration of that proposition, That the angles made by the circles of the sphere, are equal to the angles made by their representatives in the stereographic projection : but, faid he, when I laid aside that demonstration, and considered the proposition in my own way, I saw clearly that it must be true. Another Gentleman, of undoubted credit, and judgment in these matters, who had part in this conversation, remembers it distinctly.

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As to the appearance of colour, a blind man must be more at a loss; because he hath no perception that resembles it. Yet he may, by a kind of analogy, in part supply this defect. To those who see, a scarlet colour signifies an unknown quality in bodies, that makes to the eye an appearance, which they are well acquainted with, and have often observed : to a blind man, it fignifies an unknown quality that makes to the eye an appearance which he is unacquainted with. But he can conceive the eye to be variously affected by different colours, as the nose is by different smells, or the ear by different sounds. Thus he can conceive scarlet to differ from blue, as the sound of a trumpet does from that of a drum; or as the smell of an orange differs from that of an apple. It is impossible to know whether a scarlet colour has the same appearance to me which it hath to another man; and if the appearances of it to different persons differed as much as colour does from found, they might never be able to discover this difference. Hence it appears obvious, that a blind man might tais long about colours diftin&tly and

pertinently : pertinently: and if you were to examine him in the dark about the nature, composition, and beauty of them, he might be able to answer, so as not to betray his defect.

We have seen how far a blind man may go in the knowlege of the appearances which things make to the eye. As to the things which are suggested by them, or inferred from them; although he could never discover them of himself, yet he may understand them perfectly by the information of others.

And every thing of this kind that enters into our minds by the

eye, may enter into his by the ear. Thus, for instance, he would never, if left to the direction of his own faculties, have dreamed of any such thing as light: but he can be informed of every thing we know about it. He can conceive, as distinctly as we, the minuteness and velocity of its rays, their various degrees of refrangibility and reflexibility, and all the magical powers and virtues of that wonderful element. He would never of himself have found out, that there are such bodies as the sun, moon, and stars; but he may be informed of all the noble discoveries of Astronomers about their motions, and the laws of nature by which they are regulated. Thus it appears, that there is very little knowlege got by the eye, which may not be communicated by language to those who have no eyes.'

The distinction made between the visible appearances of the objects of fight, and things suggested by them, is neceffary, our Author says, to give us a just notion of the intention of nature in giving us eyes. If we attend duly to the operation of our minds in the use of this faculty, we shall perceive, that the visible appearance of objects is hardly ever regarded by us. It is not at all made an object of thought or reflection, but serves only as a sign to introduce to the mind something else, which may be distinctly conceived by those who never saw.—Thus a book or a chair has a different appearance to the eye,

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every different distance and position : yet we conceive it to be still the same; and overlooking the appearance, we immediately conceive the real figure, distance, and position of the body, of which its visible or perspective appearance is a sign and indication. A thousand instances might be produced, in order to shew, that the visible appearances of objects are intended by nature only as figns or indications; and that the mind passes instantly to the thing signified, without making the least reflection upon the sign, or even perceiving that there is any such thing. It is in a way somewhat similar, that the sounds of a language, after it is become familiar, are overlooked, and we attend only to the things signified by them.

Our Author goes on to tell us, that he cannot entertain the hope of being intelligible to those Readers who have not, by

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