46 LIFE AND DEATH. 



Domain of the Morphogenic Idea as the Last Sanc- 

 tuary of Vital Force. — We see the reason for this. 

 Physiology, in fact, has taken up its position in 

 the explanation of the functional activity of the 

 constituted organism — i.e., on a ground where 

 intervene, as we shall show further on, no energies 

 and no matter other than universal energies and 

 matter. Naturalists, on the other hand, have more 

 especially considered — and from the descriptive point 

 of view alone, at least up to the times of Lamarck 

 and Darwin — the functions, the generation, the 

 development and the evolution of species. Now 

 these functions are most refractory and inaccessible 

 to physico-chemical explanations. So, when the 

 time came to give an account of what they had done, 

 the zoologists had substituted for executive agents 

 nothing but vital force under its different names. 

 To Aristotle it is the vital force itself which, as soon 

 as it is introduced into the body of the child, moulds 

 its flesh and fashions it in the human form. Con- 

 temporary naturalists, the Americans C. O. Whitman 

 and C. Philpotts, for example, take the same line of 

 argument. Others, such as Blumenbach and Needham, 

 in the eighteenth century, invoked the same division 

 under another name, that of the nistis formativns. 

 Finally, others play with words ; they talk of heredity, 

 of adaptation, of atavism, as if these were real, active, 

 and efficient beings; while they are only appella- 

 tions, names applied to collections of facts. 



This region was therefore eminently favourable 

 to the rapid increase of hypotheses, and so they 

 abounded. There were the theories of Buffon, of 

 Lamarck, of Darwin, of Herbert Spencer, of E. 

 Haeckel, of His, of Weismann, of De Vrics, and 



