of action, so has the other retreated into the region of meditation, or vanished behind the screen of mere verbal recognition.  Whether this difference of the fortunes of Naturalism and Supernaturalism is an indication of the progress, or of the regress of humanity, of a fall from or an advance towards the higher life, is a matter of opinion.  The point to which I wish to direct attention is that the difference exists and is making itself felt.  Men are growing seriously alive to the fact that the historical evolution of humanity, which is generally, and I venture to think, not unreasonably, regarded as progress, has been and is being accompanied by a co-ordinate elimination of the supernatural from its originally large occupation of men’s thought.”

Every stage in this long process, every new attempt to place physical phenomena in a chain of direct causation has been denounced as dangerous and degrading materialism, and in this sense Huxley was not only an adherent but one of the foremost champions of materialism.  As everyone knows, some of the greatest advances in this process of co-ordinating physical phenomena were made during Huxley’s life; and his vigorous onslaughts on those who tried to thwart all attempts at material explanations in favour of unknown agencies made him specially open to abusive criticism.  The battle was almost invariably between those who had not special knowledge and those in possession of it, and it occurred in practically the whole field of science, but particularly in the biological sciences.  A single example will serve to shew what is meant by materialism in this sense and the attitude of Huxley to it.  The study of the human mind naturally has attracted the attention of thinkers almost since the beginning of philosophy, but until this century, with a few crude exceptions, it has been conducted entirely apart from anatomy and physiology.  Advances in these physical sciences, however, have changed that, and the modern psychologist has to begin by being a physiologist and anatomist.

“Surely no one who is cognisant of the facts of the case, nowadays, doubts that the roots of psychology lie in the physiology of the nervous system.  What we call the operations of the mind are the functions of the brain, and the materials of consciousness are products of cerebral activity.  Cabanis may have made use of crude and misleading phraseology when he said that the brain secretes thought as the liver secretes bile; but the conception which that much-abused phrase embodies is, nevertheless, far more consistent with fact than the popular notion that the mind is a metaphysical entity seated in the head, but as independent of the brain as a telegraph operator is of his instrument.  It is hardly necessary to point out that the doctrine just laid down is what is commonly called materialism.  I am not sure that the adjective ‘crass,’ which appears to have a special charm for rhetorical sciolists, would not be applied to it.  But it