should band themselves together and form molecules, why the molecules should fall into line and form larger bodies of matter, is not explained.
The same difficulty meets us, of course, in the philosophy of organic life. Haeckel supplies us with any number of animated pyknatoms, but we are at a loss what to do with them. How are they to form organisms? Of course, it is just as easy for them to form a simple piece of protoplasm as it is for them to form a planetary system, but there is poor consolation in that when it is a mystery how they can do either. Moreover the mysteries multiply a thousandfold when we pass from the very simplest form to the higher organisms. It is perhaps easy enough to describe what happens, to watch the process of cell division under the microscope, to trace the development through a series of stages, but why should the atoms group themselves in such a way as to form now a polyp, now a man. Each cell has its soul, it is true, unconscious impulse; and combinations of cells have corporate souls in turn, but they sit there helpless, unable to do anything; indeed what can they do, being merely a sum of vital phenomena, a collective term for the sum-total of physiological functions of the psychoplasm? The theory of evolution can not help us here, and the great Darwin frankly confessed that much. It can help us to see that if a certain form is given, that form will tend to survive if it is adapted to its surroundings, but why it should be in the first place, and why it should develop new and more appropriate characteristics in the course of time, it cannot tell us. As has been said by Schurman,[1] the theory of evolution may explain the survival of the fittest, but it can not explain the arrival of the fittest.
It is strange that Haeckel should have found it necessary to endow his atoms with souls, and then have such a dread of attributing a principle of unity to organic forms. If the atom can have a soul or energy that makes it seek out some atoms and avoid others, why not endow the organism with a soul or force that will do something? I do not mean to advocate the renewal of the doctrine of vitalism in biology, after the fashion of Reinke[2] and other modern biologists, but I do not see why a man who gives atoms and cells and groups of cells souls, and who uses the atom-souls as a principle of explanation, should draw the line at organic forces or souls. If vitalism and teleology are acceptable in the inorganic world, why should they be so utterly out of the question in the organic realm?
The philosophy of mind is also full of difficulties. The existence of psychical life is not explained, but assumed. The substance is endowed from the beginning with sentient energy, energy that feels pleasure and
