2 20 HOLISM AND EVOLUTION chap. 



for the limited goods of life, which Darwin called Natural 

 Selection. 



But it is only in certain classes of cases that the " use " 

 factor or the external or ecological stimulus of variation 

 comes into action; in others the stimulus of variation is 

 entirely internal, and must be found in the fresh mix- 

 ture and readjustment of the chromatin elements of the 

 germ-cell nucleus at certain critical stages in the evolutionary 

 process, such as in the sexual reproduction of some organ- 

 isms, or the endomixis and rejuvenescence which occur at 

 certain stages in others. 



This internal factor in Variation and Evolution was 

 stressed, and rightly stressed, by Weismann, and has 

 supplied a suggestive clue for the researches in Genetics 

 which have been conducted since his day. But the view of 

 this factor as purely mechanical has led to great difficulties 

 in detail, and has made it impossible to understand the 

 process of organic Evolution as a whole. I have therefore 

 endeavoured to stress the contrary view of this inner factor, 

 and to show that it is holistic in character and operation, 

 that it thus solves the difficulties which the mechanistic 

 hypothesis has created for itself, and that it leads to a 

 reconciliation of the two factors operative in Evolution. 

 Holism has thus once more, though in a way different from 

 that envisaged by Darwin, brought us back to the great 

 Darwinian vision of universal adaptation. 



But Holism has done more; it has enabled us to realise 

 the pervasive creative unity which makes all the diverse 

 elements of existence the co-operative members and 

 inhabitants of an essentially friendly universe. Operating 

 as the inner creative factor at the heart of things, it has led 

 to the evolution of a universe in which all the factors and 

 products, organic and inorganic alike, are not alien to and 

 destructive of each other, but are capable of mutual adapta- 

 tion, and adjustment, just because they own a common 

 origin and have an indisputable, though often scarcely 

 recognisable, family relationship. This is not to assume a 

 Pre-established Harmony, which would be as great a mistake 



