These proofs, as has been said, would, by means of the single fulcrum of protoplasm, establish, first, the identity, and, second, the materiality, of all vegetable and animal life. These are, shortly, the two propositions which we have already seen, and to which, in their order, we now pass. All organisms, then, whether animal or vegetable, have been understood for some time back to originate in and consist of cells; but the progress of physiology has _seemed_ now to substitute for cells a single matter of life, protoplasm; and it is here that Mr. Huxley sees his cue. Mr. Huxley’s very first word is the “physical basis or matter of life;” and he supposes “that to many the idea that there is such a thing may be novel.” This, then, so far, is what is _new_ in Mr. Huxley’s contribution. He seems to have said to himself, if formerly the whole world was thought kin in an “ideal” or formal element, organization, I shall now finally complete this identification in a “physical” or material element, protoplasm. In short, what at this stage we are asked to witness in the essay is, the identification of all living beings whatever in the identity of protoplasm. As there is a single matter, clay, which is the matter of all bricks, so there is a single matter, protoplasm, which is the matter of all organisms. “Protoplasm is the clay of the potter, which, bake it and paint it as he will, remains clay, separated by artifice, and not by nature, from the commonest brick or sun-dried clod.” Now here I cannot help stopping a moment to remark that Mr. Huxley puts emphatically his whole soul into this sentence, and evidently believes it to be, if we may use the word, a _clincher_. But, after all, does it say much? or rather, does it say anything? To the question, “Of what are you made?” the answer, for a long time now, and by the great mass of human beings who are supposed civilized, has been “Dust.” Dust, and the same dust, has been allowed to constitute us all. But materialism has not on that account been the irresistible result. Attention hitherto—and surely excusably, or even laudably in such a case—has been given not so much to the dust as to the “potter,” and the “artifice” by which he could so transform, or, as Mr. Huxley will have it, _modify_ it. To ask us to say, instead of dust, clay, or even protoplasm, is not to ask us for much, then, seeing that even to Mr. Huxley there still remain both the “potter” and his “artifice.” But to return: To Mr. Huxley, when he says all bricks, being made of clay, are the same thing, we answer, Yes, undoubtedly, if they are made of the same clay. That is, the bricks are identical if the clay is identical; but, on the other hand, by as much as the clay differs will the bricks differ. And, similarly, all organisms can be identified only if their composing protoplasm can be identified. To this stake is the argument of Mr. Huxley bound.