The application of the theory of language to the philosophy of the mind, Mr. Tooke has reserved for a volume by itself: the principle, however, which he means to establish, he has very explicitly laid down in the beginning of his first volume. ‘The business of the mind,’ he says, ‘as far as it concerns language, appears to me to be very simple. It extends no farther than to receive impressions, that is, to have sensations or feelings. What are called its operations, are merely the operations of language. The greatest part of Mr. Locke’s Essay, that is, all which relates to what he calls the _composition_, _abstraction_, _complexity_, _generalization_, _relation_, &c. of ideas, does indeed merely concern language. If he had been sooner aware of the inseparable connexion between words and knowledge, he would not have talked of the composition of ideas; but would have seen that the only composition was in the terms; and consequently that it was as improper to talk of a complex idea as of a complex star. It is an easy matter, upon Mr. Locke’s own principles and a physical consideration of the senses and the mind, to prove the impossibility of the composition of ideas; and that they are not ideas, but merely terms which are general and abstract.’—Vol. i. pp. 39, 51, &c. Now I grant that Mr. Locke’s own principles, and a physical consideration of the mind, do lead to the conclusion here stated, that is, to an absurdity; and it is from thence I have endeavoured to show more than once that those principles, and the considering the mind as a physical thing, are themselves absurd. How a term can be complex otherwise than from the complexity of its meaning, that is, of the idea attached to it, is difficult to understand.