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him on all sides, from without, it is plain ho could not perceive those things themselves, even in that sense of the term themselves that is understood by the vulgar; but he would nevertheless be confident that he perceives Things beyond the Curtain. He would press the Curtain against then, and consider, as his Object, their Extension and figure ; their consistence, hard or soft ; and their Motions ; which he would distinguish as of living and of dead Objects. All this, I say, he would certainly do, and never think the Curtain his Object, though it certainly is the only thing he can touch. This is no hypothesis, but a fact well known to many persons ; and familiar fact of the same nature is known to every one, though marked by none.
Thus we often think we perceive our acquintance, when in fact all that we do perceive is their clothes. We admire a five
person whose face is unseen; and never consider that we perceive only the dress which actually hides the Object of our thoughts. Such is the effect of invariable habit that even a Philosopher may never notice this fallacy with regard to mere dress; but in such cases as I first alluded to, the thing more easily admits detection. - Simple as the above described fact may appear, I think it much resembles the process of what is scientifically called perception of an external Object.–Our sensual organs are so many sorts of Curtain: the retina of the eye, for instance, is one; and, by its agitation transmitted to the Percipient, we perceive Figures, which Intellect refers to Things beyond. Here there is, with the Vulgar, a fallacy ; but neither a double Object, nor any inconvenience.
The ordinary procedure of a man behind a loose Curtain, I think, throws strong light upon the manner in which we first come to refer our Sensations to external causes. - Extension is perceived by an infant; several times before externality is inferred :-But the energy, the order, the independence on our will, and the correspondence, of Sensations soon lead it to look beyond itself for their
And here it becomes no wonder that an infant should confound the Figure it perceives, with the external cause it supposes ; when a Philosopher (while knowing to the contrary) takes a coat which he does perceive, for a man beyond it which he does not perceive; and wholly blind to the garment, thinks the hidden man his only object.
Dr. Reid has well shown us how we neglect slight Sensations, in attending to the Figures perceived with them.-Now, what I here wish to show is,—that when an Object of mere Intellect, is more interesting than the Object of Sense which leads us to it, then we neglect not only the Sensation that betrays Figure but also the Figure immediately betrayed; and the Mind is bent wholly upon a Thing beyond. -This I have clearly shown in regard of our own species: and the same holds of any inanimate Thing usually under a cover -Such as a Book-lt is this same Principle, also, (though different mode) that prevails so extensively in visual perception of Objects of three dimensions. For instance, in beholding a Sphere we by Sense perceive nothing but a round Surface variously colored; but, utterly blind to this Figure and Colors, our Intellect (governed by collateral circumstances) sees a solid Globe of one uniform Color.
The vast province of Intellect in external perception, is highly evident both herein and throughout.
Infinite is the Importance of the two General Facts Demonstrated in the Foregoing Propositions.
First-That we perceive Figure by Sense.
SECONDLY--That we perceive External Things by Intellect.
T'he extended Existence of Minds, is made certain by the first of these facts: And the dignity of our nature is evinced in the last.
Here then I rest, upon a basis which (if the fact be proced) can never be shaken. Upon this foundation, and aided by a series of observed facts, I have ventured a supposition of the Mind's distinct Existence and Operation ; which is fully developed in the Second Edition of the “ Essay on Consciousness.” The scheme offered in that essay is radically opposed to the Cerebral l'heory of Dr. Hartley, and appeals to the consideration of all who in any degree favor bis Theory. The extreme presumption of this hazard I must be supposed to feel; but the peril is miné only. What I think may be gained is the happiness of mankind: and what can be lost, is but the hope of fame to one who never had opportunity.
Here it may be permitted to add, that (wholly independent of the Spherule Hypothesis) the Essay on Consciousness contains an outline of mental Phenomena, which has the solitary claim of being a study from Nature. The originality of it will not be denied and it may not be too presumptuous to hope that it contains some new facts, not wholly unworthy of being added to the common stock.- Its author, fortunate in the truest kind of independence, has nothing to care except for the subject's sake : but, for that, as the fouudation on which he has built such hopes, he would certainly be gratified in the support, or approbation, of all who may think as he does.
FINAL DECISIVE CONSIDERATION.
The very narrow limit I had prescribed to myself for the foregoing Essay, has excluded various considerations; but there is one so highly important, that I must advert to it here, because it so completely explodes the last position upon which the opposed doctrine can hinge.
Besides the two assumptions already objected to, Dr. Reid, in his “ Inquiry,” Chap. 6. Sect. 8, asserts, that if the Eye were stituted, that rays coming from any one point of the object, were not collected in one point of the retina, but diffused over the whole,”“it would give no perception of figure or extension, but merely of color."
This, at best, is only arguing agaiust what sight is not : but even so, I am astonished that he advanced this as favorable to his cause.
- In the outset his very terms refute him : for what is “ diffusion of rays over the whole retina,” but extension ?-But, what is more, he presently qualifies his meaning to be, “the figure and magnitude of objects." Now this totally changes the position from " figure or
extension," simply expressed: and, in abandoning his first assertion his cause is lost, with all that hangs upon it.
The qualified position perfectly agrees with my own; that we thus perceive diffusion” (extension) from rays reflected by an external object, which diffusion hides the external object itself.-But Dr. Reid limits this fact, to such cases only; while I maintain that it is UNIVERSAL.-All vision must be through some medium ; and
“ cataract” is one. But even the best eye must perceive any unchanged object, (froin the same spot) under millions of various shapes and sizes ; if beheld through as many various mediums : And here, it would be as monstrous to say, that we perceive the unchanged object itself, thus often changed; as to pretend, that we perceive no figure when it differs from the object-
To illustrate this,-the hairs of a paintbrush, bounded, at one end into a circle, may represent any circular external object, reflecting rays of light: And if we apply the other end against a wall, it may be pressed into an infinity of shapes, and sizes ; but, all this time the bound end will still remain a circle. Here it is obvious, that none of those figures is either the bound circle, or so much as like to it ; and, even, if we guide the loose end into a circle, it can only resemble the bound circle; but cannot be that circle itself.
- Thus all perceived figures get their shapes, and sizes, (i. e. their existence) from a medium ; and never immediately from external objects : far less can they be erternal objects themselves.
The grand error that I here oppose, seems to arise from confounding the science of relations of extension, with its mere perception ; and thence concluding, that we cannot perceive it, in cases wherein we cannot reason upon it. But in the “ Essay on Consciousness
I have argued, that no one perception of extension, or of Color itself, could enable a man to reason upon either.-Let any one look through a piece of skin that admits light, without the proper figures of external objects, and he will be satisfied, that if he had never perceived any other thing, this must leave him in deplorable ignorance : but yet, that his field of vision is extended, as surely as it ever can be ; Or, that his percipient must, in such case, be sensible at more places than one.-Now, this last is the fact so mightily importaut to philosophy; and, it being thus highly evident, it matters not at all though the perceiver be so ignsrant, as not to know further what he does perceive.—We are assured that an idiot feels pain, which he can make no more of; and can we possibly doubt that he perceives extension, even if we could prove he understands nothing farther from it?
In no case do we perceive more "merely color,” than from various pressures upon different parts of the eye. In such experiments I vividly perceive circles, curves, and various other figures : and, since these art undoubted sensations, without any external object, if any man choose to say, they do not betray shapes, sizes, and differences ; I think it perfectly indifferent what else he may adopt. In the sense of touch itself, the opposed doctrine is equally refuted : for all internal bodily pains resemble effects of some mechanical process ; and many of them are felt, by the sufferer, as arising from external contacts. Thus touch makes us often perceive extension, without any external object.
The following simple experiments are evidences of a different kind; but also highly decisive. If we place the eye within three inches of a smooth wall, and look round for figure, we shall perceive one ; and, that it is not any figure of the wall, but only a part of our own face, round the eye.--In like manner, if we press a leg, or an arm, against the wall, we shall perceive vague figure, which is not of the wall, but of our own limb. Now it is self-evident, that whatever thing it is whose figure we perceive; it is that same thing whose extension is perceived: but, in both the above cases, it is merely so much of our own organ as is acted upon, between the external object and our percipient, that we truly perceive. Here, to prevent cavilling, I observe, that the eye and the arm are, indeed, external ohjects to each other, but the experiments supposed, are not of this RECIPROCAL kind ; for here, the eye and the arm, each, reports its own fact ; and if the eye ball projected a little, round the pupil, it is evident, we should perceive it strictly; and no figure of our face beyond it.
These experiments apply to all proper perceptions of figure or extension: for, we never perceive any thing except superficial impressions on the mind itself.--Some of these mental impressions have external causes ; and others, we know, have not :—while, of those Figures which have, some are in like superficial proportions to their external causes ; and others are distorted or unlike.-In this last case INTELLECT must consult experience, or the cross evidence of our other senses, to learn the true figure ---or, even, judge the existence, -of the external cause : and thus it is INTELLECT (and neither sense, nor instinct) that perceives (properly conceives) external objects.
In fine-Thousands of various figures without external objects, (perceived during both sleep, and vigilance, and as well by the impro