624 QUESTION AS TO EXISTENCE OF MATTER.

and independent existence of secondary, as well as of primary qualities in matter; and that there is, upon their hypothesis, exactly the same evidence for the one as for the other. The general problem, as to the probable existence of matter- unquestionably the most fundamental and momentous in the whole science of metaphysicsmay be fairly and intelligibly stated in a very few words.

Bishop Berkeley, and after him Mr. Drummond, have observed, that by our senses, we can have nothing but sensations; and that sensations, being affections of mind, cannot possibly bear any resemblance to matter, or any of its qualities; and hence they infer, that we cannot possibly have any evidence for the existence of matter; and that what we term our perception of its qualities, is in fact nothing else than a sensation in our own minds. Dr. Reid, on the other hand, distinctly admitting that the primary functions of our senses is to make us conscious of certain sensations, which can have no sort of resemblance or affinity to the qualities of matter, has asserted it as a fact admitting of no dispute, but recognised by every human creature, that these sensations necessarily suggest to us the notion of certain external existences, endowed with particular definable qualities; and that these perceptions, by which our sensations are accompanied, are easily and clearly distinguishable from the sensations themselves, and cannot be confounded with them, without the most wilful perversity. Perception, again, he holds, necessarily implies the existence of the object perceived; and the reality of a material world is thus as clearly deduced from the exercise of this faculty, as the reality of our own existence can be from our consciousness, or other sensations. It appears, therefore, that there are two questions to be considered in determining on the merits of this controversy. First, whether there be any room for a distinction between sensation and perception; and, secondly, if we shall allow such a distinction, whether perception does necessarily imply the real and external existence of the objects perceived.

If by perception, indeed, we understand, as Dr. Reid appears to have done, the immediate and positive dis

IS SENSATION IDENTICAL WITH PERCEPTION?

625

covery of external existences, it is evident that the mere assumption of this faculty puts an end to the whole question; since it necessarily takes those existences for granted, and, upon that hypothesis, defines the faculty in question to be that by which we discover their qualities. This, however, it is plain, is not reasoning, but assertion; and it is not the mere assertion of a fact, which in these subjects is the whole perhaps of our legitimate philosophy, but of something which may or may not be inferred from the fact, according to the views of the inquirer. The inquiry is an inquiry into the functions and operations of mind; and all that can possibly be stated as fact on such an occasion, must relate to the state and affections of mind only: But to assume the existence of a material world, in order afterwards to define one function of mind to be that by which it discovers material qualities, is evidently blending hypothesis in the statement, and prejudging the controversy by assumption. The fact itself, we really conceive not to be liable to any kind of doubt or dispute; and yet the statement of it, obvious as it is, seems calculated to retrench a good deal from each of the opposite assertions. The fact, if we be not greatly mistaken, is confessedly as follows.

We have occasionally certain sensations which we call heat, pain, resistance, &c. These feelings, of course, belong only to the mind, of which they are peculiar affections; and both parties are agreed in asserting, that they have no resemblance, or necessary reference, to any thing external. Dr. Reid has made this indeed the very groundwork of his reasonings on the subject of perception; and it will not probably be called in question by his antagonists, who go the length of inferring from it, that nothing but mind can be conceived to have an existence in nature. This, then, is one fact which we may safely assume as quite certain and indisputable, viz., that our sensations are affections of the mind, and have no necessary reference to any other existence. But there is another fact at least as obvious and indisputable, which the one party seems disposed to

626

PERCEPTION IS NOT SENSATION.

overlook, and the other to invest with undue authority in the discussion. This second fact is, that some of the sensations in question are uniformly and irresisti bly accompanied by the apprehension and belief of certain external existences, distinguished by peculiar qualities. The fact certainly admits of no dispute; and, accordingly, the philosophers who first attempted to prove that this belief was without foundation, have uniformly claimed the merit of disabusing mankind of a natural and universal illusion. Now this apprehension and belief in external existences, is in itself as much an affection of mind, as the sensations by which it is accompanied; and those who deny the distinction between perception and sensation, might be justified perhaps in asserting, that it is only a sensation of another kind: at the same time, as the essence of it consists in the apprehension of an independent existence, there can be no harm in distinguishing it, by a separate appellation, from those sensations which centre in the sentient being, and suggest to him no idea of any other existence. It is in this sense alone, it appears to us, that perception can be understood in strict philosophical language. It means no more than that affection of the mind which consists in an apprehension and belief in the existence of external objects.

Now in this sense of the word, there can be no doubt that there is a real distinction between mere sensation and perception; inasmuch as there is a distinction between our feelings of pain, resistance, &c., and our conception and belief of real external existences; But they differ merely as one affection of mind may differ from another; and it is plainly unwarrantable to assume the real existence of external objects as a part of the statement of a purely intellectual phenomenon. After allowing the reality of this distinction, there is still room therefore for considering the second question to which we alluded in the outset, viz., Whether perception does necessarily imply the existence of external objects.

Upon this subject we entertain an opinion which will not give satisfaction, we are afraid, to either of the con

SENSATION AND EXTERNAL EXISTENCE.

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tending parties. We think that the existence of external objects is not necessarily implied in the phenomena of perception; but we think that there is no complete proof of their nonexistence; and that philosophy, instead of being benefited, would be subjected to needless embarrassments, by the absolute assumption of the ideal theory. The reality of external existences is not necessarily implied in the phenomena of perception; because we can easily imagine that our impressions and conceptions might have been exactly as they are, although matter had never been created. Belief, we familiarly know, to be no infallible criterion of actual existence; and it is impossible to doubt, that we might have been so framed as to receive all the impressions which we now ascribe to the agency of external objects, from the mechanism of our own minds, or the particular volition of the Deity. The phenomena of dreaming, and of some species of madness, seem to afford experimental proofs of the possibility we have now stated; and demonstrate, in our apprehension, that perception, as we have defined it (i. e. an apprehension and belief of external existences), does not necessarily imply the independent reality of its objects. Nor is it less absurd to say that we have the same evidence for the existence of external objects that we have for the existence of our own sensations: For it is quite plain, that our belief in the former is founded altogether on our consciousness of the latter; and that the evidence of this belief is consequently of a secondary nature. We cannot doubt of the existence of our sensations, without being guilty of the grossest contradiction: but we may doubt of the existence of the material world, without any contradiction at all. If we annihilate our sensations, we annihilate ourselves; and, of course, leave no being to doubt or to reason. If we annihilate the external world, we still leave entire all those sensations and perceptions which a different hypothesis would refer to its mysterious agency on our minds.

On the other hand, it is certainly going too far to assert, that the nonexistence of matter is proved by such evidence as necessarily to command our assent;

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PROCESS OF SCEPTICISM.

Since it evidently implies no contradiction to suppose, that such a thing as matter may exist, and that an omnipotent being might make us capable of discovering its qualities. The instinctive and insurmountable belief that we have of its existence, certainly is not to be surrendered, merely because it is possible to suppose it erroneous; or difficult to comprehend how a material and immaterial substance can act upon each other. The evidence of this universal and irresistible belief, in short, is not to be altogether disregarded; and, unless it can be shown that it leads to actual contradictions and absurdities, the utmost length that philosophy can warrantably go, is to conclude that it may be delusive; but that it may also be true.

The rigorous maxim, of giving no faith to any thing short of direct and immediate consciousness, seems more calculated, we think, to perplex than to simplify our philosophy, and will run us up, in two vast strides, to the very brink of absolute annihilation. We deny the existence of the material world, because we have not for it the primary evidence of consciousness; and because the clear conception and indestructible belief we have of it, may be fallacious, for any thing we can prove to the contrary. This conclusion annihilates at once all external objects; and, among them, our own bodies, and the bodies and minds of all other men; for it is quite evident that we can have no evidence of the existence of other minds, except through the mediation of the matter they are supposed to animate; and if matter be nothing more than an affection of our own minds, there is an end to the existence of every other. This first step, therefore, reduces the whole universe to the mind of the individual reasoner; and leaves no existence in nature, but one mind, with its compliment of sensations and ideas. The second step goes still farther, and no one can hesitate to take it, who has ventured deliberately on the first. If our senses may deceive us, so may our memory; - if we will not believe in the existence of matter, because it is not vouched by internal consciousness, and because it is conceivable that it should not exist, we cannot consistently believe in the reality of any past impression: for