The view concerning Life which I have endeavoured to express is that it is neither matter nor energy, nor even a function of matter or of energy, but is something belonging to a different category; that by some means at present unknown it is able to interact with the material world for a time, but that it can also exist in some sense independently; although in that condition of existence it is by no means apprehensible by our senses. It is dependent on matter for its phenomenal appearance—for its manifestation to us here and now, and for all its terrestrial activities; but otherwise, I conceive that it is independent, that its essential existence is continuous and permanent, though its interactions with matter are discontinuous and temporary; and I conjecture that it is subject to a law of evolution—that a linear advance is open to it—whether it be in its phenomenal or in its occult state. It may be well to indicate what I mean by conceiving of the possibility that life has an existence apart from its material manifestations as we know them at present. (Remember note on p. 40.) It is easy to imagine that such a view is a mere surmise, having no intelligible meaning, and that it is merely an attempt to clutch at human immortality in an emotional and unscientific spirit. To this, however, I in no way plead guilty. My ideas about life may be quite wrong, but they are as cold-blooded and free from bias as possible; moreover, they apply not to human life alone, but to all life—to that of all animals, and even of plants; and they are held by me as a working hypothesis, the only one which enables me to fit the known facts of ordinary vitality into a thinkable scheme. Without it, I should be met by all the usual puzzles:—(1) as to the stage at which existence begins, if it can be thought of as "beginning" at all;[3] (2) as to the nature of individuality, in the midst of diversity of particles, and the determination of form irrespective of variety of food; (3) the extraordinary rapidity of development, which results in the production of a fully endowed individual in the course of some fraction of a century. [Footnote 3: I doubt whether _existence_ can be "begun" at all, save as the result of a juxtaposition of elements, or of a conveyance of otion. We can put things together, and we can set things in motion,—statics and kinetics,—can we do more? Ether can be strained, matter can be moved: I doubt whether we see more than this happening in the whole material universe. This dictum is elaborated elsewhere.] With it, I cannot pretend that all these things are thoroughly intelligible, but the lines on which an explanation may be forthcoming seem to be laid down:—the notion being that what we see is a temporary apparition or incarnation of a permanent entity or idea.