20 BIOLOGY AND SOCIAL PROBLEMS 



reflexes, he is not so much within the grip 

 of these agents as a fly is under the dominance 

 of its own reflexes. From the standpoint of 

 his nervous organization he is a much more 

 truly balanced organism than a fly. His acts 

 are not so abundantly purely reflex, but the 

 state of his higher nervous activities suggests 

 not only a condition of balanced reflexes, but 

 one that might be conceived to have resulted 

 from the disintegration of reflexes. The higher 

 nervous life of man, his intellectual life, seems 

 built upon two processes, the reception of im- 

 pressions through the sensory mechanism of 

 the body, and the production of voluntary acts. 

 These two operations represent in a way the 

 two parts of a reflex, and since they are abun- 

 dantly present in the higher nervous activities 

 of the human being in an essentially independ- 

 ent way, it is possible that the phylogenetic 

 beginnings of this form of intelligence may 

 have been associated with a disintegration of 

 reflexes. Certain it is that our sense organs 

 are almost continuously pouring into the cen- 

 tral organ a varied stream of impulses indica- 

 tive of the changes in the outside and yet with- 

 out calling forth any obvious responses in our 

 musculature. In a like manner, our central or- 



