sidered as little images derived from objects without; and, as the word idea still continued to be used after this original meaning had been abandoned, (as it continues still, in all the works that treat of perception,) it is not wonderful that many of the accustomed forms of expression, which were retained together with it, should have been of a kind that, in their strict etymological meaning, might have seemed to harmonize more with the theory of ideas as images, which prevailed when these particular forms of expression originally became habitual, than with that of ideas as mere states of the mind itself; since this is only what has happened with respect to innumerable other words, in the transmutations of meaning which they have received during the long progress of scientific inquiry. The idea, in the old philosophy, had been that, of which the presence immediately preceded the mental perception, the direct external cause of perception; and accordingly, it may well be supposed, that when the direct cause of perception was believed to be, not a foreign phantasm, but a peculiar affection of the sensorial organ, that word, which had formerly been applied to the supposed object, would still imply some reference to the organic state, which was believed to supply the place of the shadowy film, or phantasm, in being, what it had been supposed to be, the immediate antecedent of perception. Idea, in short, in the old writers, like the synonymous word perception at present, was expressive, not of one part of a process, but of two parts of it. It included, with a certain vague comprehensiveness, the organic change as well as the mental,-in the same way as perception now implies a certain change produced in our organs of sense, and a consequent change in the state of the mind; and hence it is surely not very astonishing, that while many expressions are found in the works of these older writers, which, in treating of ideas, have a reference to the mental part of the process of perception, other expressions are occasionally employed which relate only to the material part of the process, -since both parts of the process, as I have said, were, to a certain degree, denoted by that single word. All this might very naturally take place, though nothing more was meant to be expressed by it than these two parts of the process, the organic change, whatever it might be, and the subsequent mental change, without the necessary intervention of something distinct from both, such as Dr Reid supposes to have been meant by the term Idea.

It is this application, to the bodily part of the process, of expressions, which he considered as intended to be applied to the mental part of perception, that has sometimes misled him in the views which he has given of the opinions of former philosophers. But still more frequently has he been misled, by understanding in a literal sense phrases which were intended in a metaphorical sense, and which seem so obviously metaphorical, that it is truly difficult to account for the misapprehension. Indeed, the same metaphors, on the mere use of which Dr Reid founds so much, continue still to be used in the same manner as before he wrote. We speak of impressions on the mind,-of ideas bright or obscure, permanent or fading,—of senses, that are the inlets to our knowledge of external things, and of memory, in which this knowledge is stored, -precisely as the writers and speakers before us used these phrases; without meaning any thing more, than that certain organic changes, necessary to perception, are produced by external objects, and that certain feelings, similar to those originally excited in this manner, are afterwards renewed, with more or less permanence and vivacity, without the recurrence of the objects that originally produced them ;-and to arrange all the moods and figures of logic in confutation of mere metaphors, such as I cannot but think the images in the mind to have been, which Dr Reid so powerfully assailed, seems an undertaking not very different from that of exposing, syllogistically and seriously, all the follies of Grecian Paganism as a system of theological belief, in the hope of converting some unfortunate poetaster or poet, who still talks, in his rhymings to his mistress, of Cupid and the Graces.

There is, however, one very important practical inference to be drawn from this misapprehension,-the necessity of avoiding, as much as possible, in philosophic disquisition, the language of metaphor, especially when the precise meaning has not before been pointed out, so as to render any misconception of the intended meaning, when a metaphor is used, as nearly impossible as the condition of our intellectual nature will allow. In calculating the possibility of this future misconception, we should never estimate our own perspicuity very highly; for there is always in man a redundant facility of mistake, beyond our most liberal allowance. As Pope truly says,

"The difference is as great between

The optics seeing, as the objects seen;"

and, unfortunately, it is the object only which is in our power. The fallible optics, that are to view it, are beyond our controul; and whatever opinion, therefore, the most cautious philosopher may assert, he ought never to flatter himself with the absolute certainty, that, in the course of a few years, he may not be exhibited, and confuted, as the assertor of a doctrine, not merely different from that which he has professed, but exactly opposite to it.

The true nature of the opinions really held by philosophers is, however, to be determined by reference to their works. To this then let us proceed.

The language of Mr Locke,-to begin with one of the most eminent of these, is unfortunately, so very figurative, when he speaks of the intellectual phenomena, (though I have no doubt that he would have avoided these figures, if he could have foreseen the possibility of their being interpreted literally,) that it is not easy to show, by any single quotation, how very different his opinions as to perception were, from those which Dr Reid has represented them to be. The great question is, whether he believed the existence of ideas, as things in the mind, separate from perception, and intermediate between, the organic affection, whatever it might be, and the mental affection; or whether the idea and the perception were considered by him as the same. "In the perception of external objects," says Dr Reid, "all languages distinguish three things,-the mind that perceives,-the operation of that mind, which is called perception,—and the object perceived. Philosophers have introduced a fourth thing, in this process, which they call the idea of the object." It is the merit of shewing the nullity of this supposed fourth thing, which Dr Reid claims, and which has been granted to him, without examination. The perception itself, as a state of the mind, or, as he chooses to call it, an operation of the mind, he admits, and he admits also the organic change which precedes it. Did Mr Locke then contend for any thing more, for that fourth thing, the idea, distinct from the perception,-over which Dr Reid supposes himself to have triumphed? That he did not contend for any thing more, nor conceive the idea to be any thing different from the perception itself, is sufficiently apparent from innumerable passages both of his Essay itself, and of his

On the Intellectual Powers, Essay II. chap. xii.

admirable defence of the great doctrines of his Essay, in his controversy with Bishop Stillingfleet. He repeatedly states, that he uses the word idea, as synonymous with conception or notion, in the common use of those terms; his only reason for preferring it to notion, (which assuredly Dr Reid could not suppose to mean any thing, distinct from the mind) being, that the term notion seems to him better limited to a particular class of ideas, those which he technically terms mixed modes. That ideas are not different from perceptions is clearly expressed by him. "To ask at what time a man has first any ideas," he says, "is to ask when he begins to perceive; having ideas and perception being the same thing." If he speaks of our senses, as the inlets to our ideas, the metaphor is surely a very obvious one; or, if any one will still contend, that what is said metaphorically must have been intended really, it must be remembered, that he uses precisely the same metaphor, in cases in which the real application of it is absolutely impossible, as, for example, with respect to our perceptions or sensations, and that, if we are to understand, from his use of such metaphors, that he believed the ideas, thus introduced, to be distinct from the mind, we must understand, in like manner, that he believed our sensations and perceptions, introduced, in like manner, to be also things self-existing, and capable of being admitted, at certain inlets, into the mind as their recipient. "Our senses, conversant about particular sensible objects, do convey," he says, "into the mind, several distinct perceptions of things, according to those various ways wherein those objects do affect them."t "The senses are avenues provided by nature for the reception of sensations." I cannot but think, that these, and the similar passages that occur in the Essay, ought, of themselves, to have convinced Dr Reid, that he who thus spoke of PERCEPTIONS, conveyed into the mind, and of avenues provided for the reception of SENSATIONS, might also, when he spoke of the conveyance of ideas into the mind, and of avenues for the reception of ideas, have meant nothing more than the simple external origin of those notions, or conceptions, or feelings, or affections of mind, to which he gave the name of ideas; especially when there is not a single argument in his Essay, or in any of his works, that is founded on the substan* Essay concerning Human Understanding, B. ii. chap. i. sect. 9.

tial reality of our ideas, as separate and distinct things in the mind. I shall refer only to one additional passage, which I purposely select, because it is, at the same time, very full of the particular figures, that have misled Dr Reid, and shews, therefore, what the true meaning of the author was at the time at which he used these figures.

"The other way of retention, is the power to revive again in our minds those ideas, which after imprinting have disappeared, or have been as it were laid aside out of sight; and thus we do, when we conceive heat or light, yellow or sweet, the object being removed. This is memory, which is, as it were the storehouse of our ideas. For the narrow mind of man not being capable of having many ideas under view and consideration at once, it was necessary to have a repository to lay up those ideas, which at another time it might have use of. But our ideas being nothing but actual perceptions in the mind, which cease to be any thing, when there is no perception of them, this laying up of our ideas in the repository of the memory, signifies no more but this, that the mind has a power in many cases to revive perceptions, which it has once had, with this additional perception annexed to them, that it has had them before. And in this sense it is, that our ideas are said to be in our memories, when indeed they are actually no where, but only there is an ability in the mind when it will to revive them again, and as it were paint them a-new on itself, though some with more, some with less difficulty; some more lively, and others more obscurely."*

The doctrine of this truly eminent philosopher, therefore, is, that the presence of the external object, and the consequent organic change, are followed by an idea," which is nothing but the actual perception;" and that the laying up of these ideas in the memory, signifies nothing more, than that the mind has, in many cases, a power to revive perceptions which it has once had. All this, I conceive, is the very doctrine of Dr Reid on the subject; and to have confuted Mr Locke, therefore, if it had been possible for him, must have been a very unfortunate confutation, as it would have been also to have confuted as completely the very opinions on the subject, which he was disposed himself to maintain.

* Essay concerning Human Understanding, B. ii. chap. x. sect. 2.