"The same doctrine leads to some curious conclusions with respect to vision. Suppose the eye to be fixed in a particular position, and the picture of an object to be painted on the retina. Does the mind perceive the complete figure of the object at once, or is this perception the result of the various perceptions we have of the different points in the outline? With respect to this question, the principles already stated lead me to conclude, that the mind does at one and the same time perceive every point in the outline of the object (provided the whole of it be painted on the retina at the same instant); for perception, like consciousness, is an involuntary operation. As no two points, however, of the outline are in the same direction, every point by itself constitutes just as distinct an object of attention to the mind, as if it were separated by an interval of empty space from all the rest. If the doctrine, therefore, formerly stated be just, it is impossible for the mind to attend to more than one of these points at once; and as the perception of the figure of the object implies a knowledge of the relative situation of the different points with respect to each other, we must conclude, that the perception of figure by the eye, is the result of a number of different acts of attention. These acts of attention, however, are performed with such rapidity, that the effect with respect to us, is the same as if the perception were instantaneous.

"It may perhaps be asked, what I mean by a point in the outline of a figure, and what it is that constitutes this point one object of attention. The answer, I apprehend, is, that this point is the minimum visibile. If the point be less, we cannot perceive it; if it be greater, it is not all seen in one direction.

"If these observations be admitted, it will follow, that, without the faculty of memory, we could have had no perception of visible figure."1

The same conclusion is attained, through a somewhat different

The same view maintained by James Mill.

process, by Mr. James Mill, in his ingenious Analysis of the Phænomena of the Human Mind. This author, following Hartley and Priestley, has pushed the principle of Association to an extreme which refutes its own exaggeration, analzying not only our belief in the relation of effect and cause into that principle, but even the primary logical laws. According to Mr. Mill, the necessity under which we lie of thinking that one contradictory excludes another,— that a thing cannot at once be and not be, is only the result of asso

Elements of the Philosophy of the Human Mind, vol, i. c. ii. Works, vol. ii. p. 141–143.

ciation and custom. 1 It is not, therefore, to be marvelled at, that ⚫ he should account for our knowledge of complex wholes in perception, by the same universal principle; and this he accordingly does." "Where two or more ideas have been often re

Mill quoted.

peated together, and the association has become very strong, they sometimes spring up in such close combination as not to be distinguishable. Some cases of sensation are analogous. For example; when a wheel, on the seven parts of which the seven prismatic colors are respectively painted, is made to revolve rapidly, it appears not of seven colors, but of one uniform color, white By the rapidity of the succession, the several sensations cease. to be distinguishable; they run, as it were, together, and a new sensation, compounded of all the seven, but apparently a simple one, is the result. Ideas, also, which have been so often conjoined, that whenever one exists in the mind, the others immediately exist along with it, seem to run into one another, to coalesce, as it were, and out of many to form one idea; which idea, however in reality complex, appears to be no less simple than any one of those of which it is compounded."

"It is to this great law of association that we trace the formation of our ideas of what we call external objects; that is, the ideas of a certain number of sensations, received together so frequently that they coalesce as it were, and are spoken of under the idea of unity. Hence, what we call the idea of a tree, the idea of a stone, the idea of a horse, the idea of a man.

"In using the names, tree, horse, man, the names of what I call objects, I am referring, and can be referring, only to my own sensations; in fact, therefore, only naming a certain number of sensations, regarded as in a particular state of combination; that is, concomitance. Particular sensations of sight, of touch, of the muscles, are the sensations, to the ideas of which, color, extension, roughness, hardness, smoothness, taste, smell, so coalescing as to appear one idea, I give the name, idea of a tree.

*

"Some ideas are by frequency and strength of association so closely combined, that they cannot be separated. If one exists, the other exists along with it, in spite of whatever effort we make to disjoin them.

"For example; it is not in our power to think of color, without thinking of extension; or of solidity, without figure. We have

1 Chap. iii. p. 75. — Ed.

2 Chap. iii. p. 68. - ED,

3 Chap. iii. p. 70.-ED.

seen color constantly in combination with extension,- spread, as it were, upon a surface. We have never seen it except in this connection. Color and extension have been invariably conjoined. The idea of color, therefore, uniformly comes into the mind, bringing that of extension along with it; and so close is the association, that it is not in our power to dissolve it. We cannot, if we will, think of color, but in combination with extension. The one idea calls up the other, and retains it, so long as the other is retained.

The counter alternative maintained against Stewart and Mill.

"This great law of our nature is illustrated in a manner equally striking, by the connection between the ideas of solidity and figure. We never have the sensations from which the idea of solidity is derived, but in conjunction with the sensations whence the idea of figure is derived. If we handle anything solid, it is always either round, square, or of some other form. The ideas correspond with the sensations. If the idea of solidity rises, that of figure rises along with it. The idea of figure which rises, is, of course, more obscure than that of extension; because figures being innumerable, the general idea is exceedingly complex, and hence, of necessity, obscure. But, such as it is, the idea of figure is always present when that of solidity is present; nor can we, by any effort, think of the one without thinking of the other at the same time." Now, in opposition to this doctrine, nothing appears to me clearer than the first alternative, and that, in place of ascending upwards from the minimum of perception to its maxima, we descend from masses to details. If the opposite doctrine were correct, what would it involve? It would involve as a primary inference, that, as we know the whole through the parts, we should know the parts better than the whole. Thus, for example, it is supposed that we know the face of a friend, through the multitude of perceptions which we have of the different points of which it is made up; in other words, that we should know the whole countenance less vividly than we know the forehead and eyes, the nose and mouth, etc., and that we should know each of these more feebly than we know the various ultimate points, in fact, unconscious minima, of perceptions, which go to constitute them. According to the doctrine in question, we perceive only one of these ultimate points at the same instant, the others by memory incessantly renewed. Now let us take the face out of perception into memory altogether. Let us close our eyes, and let us represent in imagination the countenance of our friend. This we can do with the utmost vivacity; or, if we see a picture of it, we can determine,

The doctrine of these philosophers implies, that we know the parts better than the whole.

This supposition shown to be errone

ous.

with a consciousness of the most perfect accuracy, that the portrait is like or unlike. It cannot, therefore, be denied that we have the fullest knowledge of the face as a whole, that we are familiar with its expression, with the general result of its parts. On the hypothesis, then, of Stewart and Mill, how accurate should be our knowledge of these parts themselves. But make the experiment. You will find that, unless you have analyzed, — unless you have descended from a conspectus of the whole face to a detailed examination of its parts, - with the most vivid impression of the constituted whole, you are almost totally ignorant of the constituent parts. You may probably be unable to say what is the color of the eyes, and if you attempt to delineate the mouth or nose, you will inevitably fail. Or look at the portrait. You may find it unlike, but unless, as I said, you have analyzed the countenance, unless you have looked at it with the analytic scrutiny of a painter's eye, you will assuredly be unable to say in what respect the artist has failed, you will be unable to specify what constituent he has altered, though you are fully conscious of the fact and effect of the alteration. What we have shown from this example may equally be done from any other, a house, a tree, a landscape, a concert of music, etc. But it is needless to multiply illustrations. In fact, on the doctrine of these philosophers, if the mind, as they maintain, were unable to comprehend more than one perceptible minimum at a time, the greatest of all inconceivable marvels would be, how it has contrived to realize the knowledge of wholes and masses which it has. Another refutation of this opinion might be drawn from the doctrine of latent modifications, the obscure perceptions of Leibnitz, of which we have recently treated. But this argument I think unnecessary.1

1 Show this also, 1°, By the millions of acts of attention requisite in each of our perceptions. [Cf. Dr. T. Young's Lectures on Natural Philosophy, vol. ii. Ess. v. The Mechanism

of the Eye, iii. p. 574, edit. 1807.- ED.] 2o, By imperfection of Touch,which is a synthetic sense, as Sight is analytic.— Marginal Jotting.

LECTURE XXVII.

THE PRESENTATIVE FACULTY.

1. PERCEPTION. GENERAL QUESTIONS IN RELATION TO THE SENSES.

IN

In my last Lecture, I was principally occupied in showing that the hypothesis of a Representative Perception considRecapitulation. ered in itself, and apart from the grounds on which philosophers have deemed themselves authorized to reject the fact of consciousness, which testifies to our immediate perception of external things, violates, in many various ways, the laws of a legitimate hypothesis; and having, in the previous Lecture, shown you that the grounds on which the possibility of an intuitive cognition of external objects had been superseded, are hollow, I thus, if my reasoning be not erroneous, was warranted in establishing the conclusion that there is nothing against, but everything in favor of, the truth of consciousness, and the doctrine of immediate perception. At the conclusion of the Lecture, I endeavored to prove, in opposition to Mr. Stewart and Mr. Mill, that we are not percipient, at the same instant, only of certain minima, our cognitions of which are afterwards, by memory or association, accumulated into masses; but that we are at once and primarily percipient of masses, and only require analysis to obtain a minute and more accurate knowledge of their parts, — that, in short, we can, within certain limits, make a single object out of many. For example, we can extend our attentive perception to a house, and to it as only one object; or we can contemplate its parts, and consider each of these as separate objects.1

Resuming consideration of the more important psychological questions that have been agitated concerning the Senses, I proceed to take up those connected with the sense of Touch.

1 Sir W. Hamilton here occasionally introduced an account of the mechanism of the organs of Sense; observing the following order, Sight, Hearing, Taste, Smell, and Touch. This, he remarks, is the reverse of the order of nature, and is adopted by him because under Touch certain questions arise, the discussion of which requires some preliminary knowledge of the nature of the

senses. As the Lecture devoted to this subject mainly consists of a series of extracts from Young and Bostock, and is purely physiological, it is here omitted. See Young's Lectures on Natural Philosophy, vol. i. pp. 387, 447 et seq.; vol. ii. p. 574, (4to edit.) Bostock's Physiology, pp. 692 et seq., 723, 729-733. (3d edit.)-ED.