108 SOCIAL EVOLUTION 



These modified activities reacted upon nerve and brain. 

 ''Through nerve and brain they reacted further, physi- 

 ologically and morphologically, upon the whole organism. 

 By every advance in association the bodily organism was 

 necessarily modified in some degree to correspond to the 

 development of feeling and intelligence." 7 Out of disci- 

 pline for antipathies and sympathies new variations 

 arose and were encouraged ; that is, when they appeared 

 as specific traits in an individual, that individual was not 

 crushed with disapproval and contempt, but was allowed 

 to live and so transmit these qualities. 



By looking closer at the process of association we are 

 able to see more clearly the course of action through 

 which the brute mind was gradually converted into the 

 human intellect. From what has already been said of 

 life in society one may readily see that in group life 

 the relations of an individual to his surroundings and to 

 his companions became increasingly complex. And yet 

 the simplest psychophysical process that takes place in 

 the nervous system is the response of nervous matter 

 to an external stimulus. 8 When any sense organ is 

 stimulated a twofold result normally follows: one effect 

 is a sensation, an elementary fact of consciousness; the 

 other effect is a muscular movement called a reflex. We 

 shall follow the usage of Professor Giddings and denote 

 by the term, ' l response to stimulus, ' ' both aspects of the 

 process. It is this phenomenon of stimulation and re- 

 sponse that leads us to the very heart of the matter. 



There are roughly two kinds of stimuli. Original or 

 primary stimuli include: fellow beings, the concrete ob- 

 jects of nature, events of nature, in fact, most external 

 i Hid., p. 200. 



s Giddings, F. H. Descriptive and Historical Sociology, 1906, p. 124. 



