THE STRUGGLE FOR REALITIES. 369 



his entrances." He is a rare man who can add a new 

 meaning to his lines or give a better cue to him that 

 follows. 



The nervous system of man and animals is primarily 

 a device for making locomotion safe. The mind — using 



the word in the broadest sense — is a col- 

 Nature of the lective term for the operations of the 

 mind. t • . 



nervous system. It is not an entity ex- 

 isting apart from organization. To it consciousness is 

 related much as the flame is to fire. The mind is in 

 operation whether we realize it or not. The reflex ac- 

 tion of the nerve centre is the type of all mind pro- 

 cesses. Through the sensory nerves, impressions of the 

 external world are received by the brain or central gan- 

 glion. The brain has no source of knowledge other 

 than through sensation. All human knowledge comes 

 through human experience. The primal function of the 

 brain, sitting in darkness, is to convert sensory impres- 

 sions into impulses of action. To this end are devel- 

 oped the motor nerves which pass from the nerve cen- 

 tre outward to the muscles. The sensory organs are 

 the brain's sole teacher; the muscles are its only serv- 

 ants. The essence of the intellect, as distinguished 

 from reflex or instinctive action, is the choice among 

 dift'erent motor responses to the stimulus of external 

 conditions. As the conditions of life grow more com- 

 plicated, the possible ways in which sensation may pass 

 over into action grow more numerous. It is the func- 

 tion of the intellect to consider these, and of the will to 

 choose. The growth of the intellect causes and permits 

 complexity of life. Safety in life depends upon choos- 

 ing the right response. Wrong choice leads to failure 

 and death. The power of choice implies the necessity 

 of choosing right. 



From this, by the process of natural selection, arises 



