THE EVOLUTION OF MIND 



becomes possible in those compound nervous 

 systems which respond to a great number of in- 

 frequent and special relations. For the estab- 

 lishment of inner relations, answering to these 

 infrequent and special outer relations, involves 

 a lapse of time during which numerous diverse 

 impressions are getting distributed through va- 

 rious transit lines hitherto little used. When, 

 as in the fully developed human cerebrum, a 

 vast number of infrequent and special relations 

 are continually set up, there is a maximum of 

 nutritive change, there is a maximum of time 

 during which impressions simultaneously com- 

 ing in may be compared and classified, and there 

 is a maximum of consciousness. 



This explanation of the way in which the va- 

 rious phases of conscious psychical life arise is 

 fully confirmed by the way in which they dis- 

 appear when actions at first consciously per- 

 formed become instinctive. The confirmation 

 is so complete as to afford a very strong proof 

 of the truth of the hypothesis. Many of the 

 actions performed by civilized man are desig- 

 nated by psychologists as " secondarily auto- 

 matic." That is, they are at first performed with 

 the assistance of reason, volition, and conscious 

 memory, and they are attended by feelings of 

 pleasure or pain. But after a while they are per- 

 formed without the aid of reason, volition, or 

 conscious memory, and they are not attended 

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