It is, however, one thing to show that there is no insuperable objection to accepting the existence of such infra-conscious states, if such existence be otherwise probable, and another thing to establish this probability. And this leads us back again to the grounds on which their existence may fairly be regarded as probable. We are told that the mental faculties of the dog in common with his physical or organic frame, have arisen in the course of ages by a process of development. It is clear that such a statement is intended to apply to the living dog with active faculties; to a _going_ mechanism, or rather organism which is also conscious. Well and good. The material structure has been evolved from lower forms of matter: the organic modes of energy (in virtue of which he lives), from lower forms of energy, the mental states (in virtue of which he is conscious), from—what? I suggest in continuation and conclusion of this sentence—from lower forms of infra-consciousness; that is to say, of what is of the same order of existence as consciousness, but has not yet risen to the level of consciousness. Many people will no doubt see no necessity for such a conclusion. It is making an unnecessary bother, they will say, about a very simple matter. At some undefined stage of organic evolution—perhaps when nervous tissue had its genesis, perhaps earlier—consciousness began to dawn and has since developed in clearness and brightness during the evolution of higher and higher organisms. According to this view, the ascending curve of evolution is divisible at some undefined point into two portions: of which one represents organic evolution previous to the dawn of consciousness; the other organic evolution subsequent to the dawn of consciousness. But the question at once suggests itself: From what did consciousness dawn at this undefined point? In answer to which there are some who do not hesitate to reply that the consciousness arose out of the physical conditions; that when the rhythmic dance of organic molecules reached a certain intensity and intricacy consciousness was developed. There is, indeed, a certain class of nerve-physiologists, or of medical men who write on nerve-physiology, who, if they do not hold that states of consciousness are generated from the energy which accompanies the working of the brain-tissues, at any rate write as if this was their belief. But such a view is quite untenable. If there is one thing clearly established, both by those who have approached the matter from the scientific side, and by those who have approached the matter from the metaphysical side, it is that the distinction between energy and consciousness is radical and absolute. No conceivable increase in the orderly complexity of the molecular vibrations of brain-tissue could give rise to that consciousness which differs _toto cœlo_ from any manifestation of energy.