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case, indeed, the rapidity of thought is so remarkable, that if the different acts of the mind were not all necessarily accompanied with different movements of the eye, there can be no reason for doubting, that the philosophers, whose doctrine I am now controverting, would have asserted, that they are all mathematically co-existent.

Upon a question, however, of this sort, which does not admit of a perfectly direct appeal to the fact, I would by no means be understood to decide with confidence; and therefore I should wish the conclusions I am now to state, to be received as only conditionally established. They are necessary and obvious consequences of the general principle, "that the mind can only attend to one thing at "once ;" but must stand or fall with the truth of that supposition.

It is commonly understood, I believe, that, in a concert of music, a good ear can attend to the different parts of the music separately, or can attend to them all at once, and feel the full effect of the harmony. If the doctrine, however, which I have endeavoured to establish, be admitted, it will follow, that, in the latter case, the mind is constantly varying its attention from one part of the music to the other, and that its operations are so rapid, as to give us no perception of an interval of time.

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.

In farther confirmation of this reasoning, it may be remarked, that if the perception of visible figure were an immediate consequence of the picture on the retina, we should have, at the first glance, as distinct an idea of a figure of a thousand sides, as of a triangle or a square. The truth is, that when the figure is very simple, the process of the mind is so rapid, that the perception seems to be instantaneous; but when the sides are multiplied beyond a certain number, the interval of time necessary for these different acts of attention becomes perceptible.

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.

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CHAPTER THIRD.

OF CONCEPTION.

Br Conception, I mean that power of the mind, which enables it to form a notion of an absent object of percep tion, or of a sensation which it has formerly felt. I do not contend that this is exclusively the proper meaning of the word, but I think that the faculty which I have now defined deserves to be distinguished by an appropriate

name.

Conception is often confounded with other powers. When a painter makes a picture of a friend, who is absent or dead, he is commonly said to paint from memory: and the expression is sufficiently correct for common conver sation. But in an analysis of the mind, there is ground for a distinction. The power of conception enables him to make the features of his friend an object of thought, so as to copy the resemblance, the power of memory recognises these features as a former object of perception. Every act of memory includes an idea of the past; conception implies no idea of time whatever.*

According to this view of the matter, the word conception corresponds to what was called by the schoolmen simple apprehension; with this difference only, that they included, under this name, our apprehension of general propositions, whereas I should wish to limit the applica

* Shakespeare calls this power "the mind's eye."
Hamlet." My father! Methinks I see my father.
Horatio." Where, my Lord?

Hamlet." In my mind's eye, Horatio."

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tion of the word conception to our sensations, and the objects of our perceptions. Dr. Reid, in his Inquiry, substitutes the word conception instead of the simple apprehension of the schools, and employs it in the same extensive signification. I think it may contribute to make our ideas more distinct, to restrict its meaning :-and for such a restriction, we have the authority of philosophers in a case perfectly analogous.-In ordinary language, we apply the same word perception, to the knowledge which we have by our senses of external objects, and to our knowledge of speculative truth and yet an author would be justly censured, who should treat of these two operations of the mind under the same article of perception. I apprehend there is as wide a difference between the concep. tion of a truth, and the conception of an absent object of sense, as between the perception of a tree, and the perception of a mathematical theorem.-I have therefore taken the liberty to distinguish also the two former operations of the mind: and under the article of conception shall confine myself to that faculty, whose province it is to enable us to form a notion of our past sensations, or of the objects of sense that we have formerly perceived.

Conception is frequently used as synonymous with imagination. Dr. Reid says, that "imagination, in its proper "sense, signifies a lively conception of objects of sight." "This is a talent" (he remarks) of importance to poets "and orators; and deserves a proper name, on account "of its connection with their arts." He adds, that "im"agination is distinguished from conception, as a part "from a whole."

I shall not inquire, at present, into the proper English meaning of the words conception and imagination. In a study such as this, so far removed from the common purposes of speech, some latitude may perhaps be allowed

in the use of words, provided only we define accurately those we employ, and adhere to our own definitions.

The business of conception, according to the account I have given of it, is to present us with an exact transcript of what we have felt or perceived. But we have moreover, a power of modifying our conceptions, by combining the parts of different ones together, so as to form new wholes of our own creation. I shall employ the word imagination to express this power: and, I apprehend, that this is the proper sense of the word; if imagination be the power which gives birth to the productions of the poet and the painter. This is not a simple faculty of the mind. It presupposes abstraction, to separate from each other qualities and circumstances which have been perceived in conjunction, and also judgment and taste to direct us in forming the combinations. If they are made wholly at

random, they are proofs of insanity.*

The first remarkable fact which strikes us with respect to conception is, that we can conceive the objects of some senses much more easily than those of others, Thus we can conceive an absent visible object, such as a building that is familiar to us, much more easily than a particular sound, a particular taste, or a particular pain, which we have formerly felt. It is probable, however, that this

* In common discourse, we often use the phrase of thinking upon an object, to express what I here call, the conception of it.—In the following passage, Shakespeare uses the former of these phrases, and the words imagination and apprehension as synonymous with each other.

-Who can hold a fire in his hand,
By thinking on the frosty Caucasus ?
Or cloy the hungry edge of appetite,
By bare imagination of a feast?
Or wallow naked in December's snow,
By thinking on fantastic summer's heat?
Oh no! the apprehension of the good
Gives but the greater feeling to the worse.

K. RICHARD II. Act i. Scene 6.

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