GROWTH AND REPRODUCTION 



THERE are two dominant and persistent problems 

 in biology correlated with definite functional powers 

 which lie at the heart of human life. These are the 

 problem of reproduction and growth, on the one 

 hand, and the problem of consciousness, on the other. 

 The human animal may be considered to have two 

 sets of duties and privileges which transcend all 

 others : those connected with the maintenance of 

 the race through his own person, and those connected 

 with the growth of his personality. The former 

 duties and privileges have to do with a definite group 

 of cells given over wholly to the function of repro- 

 duction. The latter have to do with an equally 

 definite type of cells, the nerve cells of the nervous 

 system, and especially the cells of the mantle or 

 cortex of the brain and the pathways between them. 



It is a highly clarifying view, and a wholly legiti- 

 mate one, to regard the entire human mechanism 

 as preeminently subserving these two sets of ele- 

 mentary functions for reproduction and for the 

 higher activities of the nervous system. And diffi- 

 cult as is the task of tracing the relations of these 

 purposes to the machinery of the body, it is no 



41 



