processes. This is in one sense
true. No doubt at all that if these processes were arrested, life would speedily end, but do they alone account for its origin? Is it not like accounting for a baby in terms of its breathing and eating? It was
a baby before it did either, and it would seem as if life must in some way ante-date the physical and chemical processes that attend it, or at least be bound up in them in a way that no scientific analysis can reveal. If life is merely a mode of motion in matter, it is fundamentally unlike any and all other modes of motion, because, while we can institute all the others at will, we are powerless to institute this. The mode of motion we call heat is going on in varying degrees of velocity all about us at all times and seasons, but the vital motion of matter is limited to a comparatively narrow circle. We can end it, but we cannot start it. The rigidly scientific type of mind sees no greater mystery in the difference in contour of different animal bodies than a mere difference in the density of the germ cells: "one density results in a sequence of cell-densities to form a horse; another a dog; another a cat"; and avers that if we "repeat the same complex conditions, the same results are as inevitable as the sequences of forces that result in the formation of hydrogen monoxide from hydrogen and oxygen." Different degrees of density may throw light on the different behavior of gases and fluids an