faithful representation:—"Dr Reid," says Mr Stewart, "was the first person who had courage to lay completely aside all the common hypothetical language concerning perception, and to exhibit the difficulty, in all its magnitude, by a plain statement of the fact. To what, then, it may be asked, does this statement amount? Merely to this; that the mind is so formed that certain impressions produced on our organs of sense, by external objects, are followed by corresponding sensations, and that these sensations, (which have no more resemblance to the qualities of matter, than the words of a language have to the things they denote,) are followed by a perception of the existence and qualities of the bodies by which the impressions are made;—that all the steps of this process are equally incomprehensible."[1] There are at least two points which are well worthy of being attended to in this quotation. First, Mr Stewart says that Reid "exhibited the difficulty of the problem of perception, in all its magnitude, by a plain statement of fact." What does that mean? It means this; that Reid stated, indeed, the fact correctly—namely, that external objects give rise to sensations and perceptions, but that still his statement did not penetrate to the heart of the business, but by his own admission, left the difficulty undiminished. What difficulty? The difficulty as to how external objects give rise to sensations and perceptions. Reid did not undertake to settle that point—a wise declinature, in the estimation of Mr Stewart. Now Mr Stewart, understanding, as he did, the philosophy of causation, ought to have known that every difficulty as to how one thing gives rise to another, is purely a difficulty of the mind's creation, and not of nature's making, and is, therefore, no difficulty at all. Let us explain this,—a man says he knows that fire explodes gunpowder; but he does not know how or by what means it does this. Suppose, then, he finds out the means, he is still just where he was; he must again ask how or by what means these discovered means explode the gunpowder; and so on ad infinitum. Now the mind may quibble with itself for ever, and make what difficulties it pleases in this way; but there is no real difficulty in the case. In considering any sequence, we always know the how or the means as soon as we know the that or the fact. These means may be more proximate or more remote means, but they are invariably given either proximately or remotely along with and in the fact. As soon as we know that fire explodes gunpowder, we know how fire explodes gunpowder,—for fire is itself the means which explodes gunpowder,—the how by which it is ignited. In the same way, if we knew that matter gave rise to perception, there would be no difficulty as to how it did so. Matter would be itself the means which gave rise to perception. We conceive, therefore, that Mr Stewart did not consider what he was saying when he affirmed that Reid's plain statement of facts exhibited the 'difficulty in all its magnitude. If Reid's statement be a statement of fact, all difficulty vanishes,—the question of perception is relieved from every species of perplexity. If it be the fact that perception is consequent on the presence of matter, Reid must be admitted to have explained, to the satisfaction of all mankind, how perception is brought about. Matter is itself the means by which it is brought about.
Secondly, then—Is it the fact that matter gives rise to perception? That is the question. Is it the fact that these two things stand to each other in the relation of antecedent and consequent? Reid's "plain statement of fact," as reported by Mr Stewart, maintains that they do. Reid lays it down as a fact, that perceptions follow sensations, that sensations follow certain impressions made on our organs of sense by external objects, which stand first in the series. The sequence, then, is this—1st, Real external objects; 2d, Impressions made on our organs of sense; 3d, Sensations; 4th, Perceptions. It will simplify the discussion if we leave out of account Nos. 2 and 3, limiting ourselves to the statement that real objects precede perceptions. This is declared to be a fact—of course an ob-
- ↑ Elements of the Philosophy of the Human Mind. Part I. ch. i.
