260 HEREDITY AND SELECTION IN SOCIOLOGY 



we may say that the organism is the seat of chemical reactions 

 of two sorts, the one destructive, the other synthetic and con- 

 structive. The sum of these reactions constitute the phenomena 

 of nutrition. Life is a succession of phenomena of assimilation 

 and disassimilation, of construction and disruption, of anabolism 

 and katabolism. 



In the biological as in the social organism, excessive kata- 

 bolism or disassimilation implies reduction of the vital power. 

 There is no longer correspondence between the potential strength 

 of the organism and its physiological activity ; and physiological 

 activity carried to excess is pathological. All social life 

 implies loss. Death is, as we have seen, an institution which 

 exists for the benefit of the species ; or, at least, for those 

 species which have passed the unicellular stage of organisation. 

 And death is an institution which is indispensable for the 

 continuance of social life. In the struggle for existence between 

 societies, and in the struggle between individuals belonging 

 to the same society, the feebler must be exterminated. The 

 law of selection is a beneficial one ; it is a law which, if allowed 

 to operate normally and without restriction, has as its result 

 the constant improvement of organic life. We saw, in the 

 first part of this work, that Nature requires an immense number 

 of forms, a vast wealth of organic hfe, in order that selection 

 may have free play. We saw that all the apparently reckless 

 extravagance of Nature in this respect is justified by the aim 

 which is implied in the whole organic process — the conservation 

 of the species. And it must be evident to anyone at all familiar 

 with biological phenomena that the conservation and ultimate 

 perfecting of a species can only be secured at the price of a 

 tremendous sacrifice of individual life. 



But the very fact that the conservation of the species is its 

 raison d'etre in itself justifies this sacrifice of individual life; 

 for, as a general law, those individuals who are sacrificed are 

 precisely those who are of least use to the species, the weak, 



