136 LIFE AND DEATH. 



I consider death as an adaptation, and believe that it has arisen 

 by the operation of natural selection. Gotte l , however, concludes 

 from this that 'the first origin of hereditary and consequently 

 (for the organization in question) necessary death, is not explained 

 but already assumed.' ' The operation and significance of the 

 principle of utility consists in selecting- the fittest from among 

 the structures and processes which are at hand, and not in directly 

 creating new ones. Every new structure arises at first, quite 

 independently of any utility, from certain material causes present 

 in a number of individuals, and when it has proved useful and is 

 transmitted, it extends, according to the laws of the survival of the 

 fittest, in the group of animals in which it appeared. This exten- 

 sion will undergo further increase with every advance in utility 

 which results from further structural changes, until it extends 

 over the whole group. So that usefulness effects the preservation 

 and the distribution of new structures, but has nothing whatever 

 to do with the causes of their primary origin and their consequent 

 transmission to all other individuals. Indeed, on these hereditary 

 causes the necessity of the structures in question depends, so that 

 their usefulness in no way explains their necessity.' 



' These conclusions, when applied to the origin of natural death 

 called forth by internal causes, would show that it became inevitable 

 and hereditary in a number of the originally immortal Metazoa, 

 before there could be any question as to the benefits derived from its 

 influence. Such influence must have consisted in the fact that more 

 descendants survived the struggle for existence and were able to 

 enter upon reproduction among the individuals which had inherited 

 the predisposition to die than among the potentially immortal 

 beings which would be damaged in the struggle for existence, 

 and would therefore be exposed to still further injuries. The exist- 

 ing necessity for natural death in all Metazoa might therefore be 

 derived in an unbroken line of descent from the first mortal 

 Metozoan, of which the death became inevitable from internal 

 causes, before the principle of utility could operate in favour of its 

 dissemination.' 



In reply to this I would urge : that it has been very often 

 maintained that natural selection can produce nothing new, but 

 can only bring to the front something which existed previously to 



1 1. c., p. 5. 



