A multitude of things obviously perish, thereby showing themselves to be trivial or accidental arrangements, according to our hypothesis. A flame is extinguished and dies, a mountain is ultimately ground into sand by the slow influence of denudation, a planet or a sun may lose its identity by encounter with other bodies. All these are temporary collocations of atoms; and it appears now that an atom may break up into electric charges, and these again may some day be found capable of resolving themselves into pristine ether. If so, then these also are temporary, and in the material universe it is the ether only which persists—the Ether with such states of motion or strain as it eternally possesses—in which case the Ether will have proved itself the material substratum and most fundamental known entity on that side. But are we to conclude, therefore, that nothing else exists? that the existence of one thing disproves the existence of others? The contention would be absurd. The category of _life_ has not been touched in anything we have said so far; no relation has been established between life and energy, or between life and ether. The nature of life is unknown. Is life also a thing of which constancy can be asserted? When it disappears from a material environment is it knocked out of existence, or is it merely transferred to some other surroundings, becoming as difficult to identify and recognise as are the gases of a burnt manuscript or the vapour of a vanished cloud? Is it a temporary trivial collocation associated with certain complex groupings of the atoms of matter, and resolved into nothingness when that grouping is interfered with? or is it something immaterial and itself fundamental, something which uses these collocations of matter in order to display itself amid material surroundings, but is otherwise essentially independent of them? (This idea is expanded in Chapters VI. to X., and see note at end of present chapter.) Professor Haeckel would answer this question with a contemptuous negative; and the treatment which he would thus give to life he would also extend to mind and consciousness, to affection, to art, to poetry, to religion, and all the other facts of experience to which in the process of evolution humanity has risen: I say he would answer the question, whether these had any real existence other than as a necessary concomitant of a sufficiently complex material aggregate, with a contemptuous negative; but I challenge him to say by what right he gives that answer. His speculation is that all these properties are nascent and latent in the material atoms themselves, that these have the potentiality of life and choice and consciousness, which we perceive in their developed combinations. As a speculation this is legitimate; but the only answer that can by science legitimately be given at the present time is the answer given by du Bois-Reymond, _ignoramus_, we do not know.