344 THE VARIATION OF ANIMALS IN NATURE 



be treated with the completeness which has been accorded 

 to others. It is, however, imperative to call attention to 

 them and allow them due weight, because they constitute 

 a serious contribution to the subject and a challenge to the 

 orthodox outlook. We limit ourselves to a selection of what 

 appear to be the most important and at the same time the 

 most relevant to what is, after all, a strictly biological inquiry. 

 The particular views we have selected are Bergson's theory of 

 Creative Evolution (191 1), Russell's work on ' Psycho-biology' 

 (1924), and Smuts's concept of ' Holism ' (1926). It should 

 be noted that, while these works are concerned with the 

 specific problems of evolution and development, they are part 

 of that revolt against mechanistic principles which is also 

 seen in its strictly philosophical expression in the writings of 

 J. S. Haldane and A. N. Whitehead. 



(a) As is well known, Bergson holds that the phenomena 

 of evolution are the expression of an impulsion manifested 

 by living organisms. This impulsion is not fixed and pre- 

 determined. It has the character of spontaneity manifested 

 in the continuous creation of new forms, and it is, as it were, 

 inherent in and characteristic of life. What has given evolu- 

 tion its diversity is the fact that life has had to wrestle with 

 and overcome the inertia of the material with which it has 

 to act. The essence of the theory is contained in a passage 

 of remarkable vigour and imaginative breadth (I.e. p. 259) : 

 ' all our analyses show us, in life, an effort to remount the 

 incline that matter descends. In that they reveal to us the 

 possibility, the necessity even of a process, the inverse of 

 materiality, creative of matter by its interruption alone. The 

 life that evolves on the surface of our planet is indeed attached 

 to matter ... in fact it is riveted to an organism that subjects 

 it to the general laws of inert matter. But everything happens 

 as if it were doing its utmost to set itself free from these laws. 

 . . . Incapable of stopping the course of material changes, 

 it succeeds in retarding them.' Adaptation is, he admits, 

 a necessary condition of evolution, but the environment is 

 merely a thing life has to reckon with. ' Adaptation explains 

 the sinuosities of the movements of evolution, but not its 

 general direction, still less the movement itself (p. 107). 

 Concerning the nature of this elan vital, it is enough to say 

 that, like Eimer's orthogenesis, it is a force continued from 



