CHAPTER XX 

 REFLEX ACTION, INSTINCT, AND REASON 



Mind is associated with nervous tissue It is adaptive It is related to move- 

 ment The evolution of mind Reflex and voluntary actions Intelligence and 

 reason Memory Traditional knowledge The mental characteristics of ants 

 The instincts of man Sucking Crying Weariness Hunger Thirst Imita- 

 tiveness Sexual and parental love The mutation theory The importance of 

 mental acquirements. 



A 1 



607. ^ MASS of evidence indicates that mind is especially 

 associated with nervous tissue. In fact, there is no 

 clear evidence that consciousness, even in the form 

 of the most rudimentary feeling, is anywhere present except in 

 conjunction with those masses of nerve cells which are termed 

 ganglia, the largest of which is the brain. Mind appears to be 

 rudimentary, or even non-existent in animals in which ganglia 

 are relatively little developed or absent. It is found in greater 

 amplitude in the higher animals in which the ganglia are better 

 developed. In the highest animals it appears associated exclusively 

 with the brain. Moreover, mind seems invariably associated, not 

 only with ganglia, but also with sense organs eyes, ears, tactile, 

 and taste organs, and the like which are mostly situated at, or 

 near, the surface of the body, and which receive from the external 

 world and transmit to the ganglia messages (stimuli) derived from 

 light, sound, contact, and the like messages which in some way 

 awaken an activity which is correlated to consciousness. 



608. Mind is useful to the animal that possesses it only in so 

 far as it controls his actions by initiating, guiding, or inhibiting 

 them. If the animal is of a relatively simple type, living in a com- 

 paratively simple environment, his equipment of nervous tissue 

 and mind is correspondingly simple. If, on the other hand, he 

 is fitted for more complex surroundings, and if, therefore, his 

 activities must be adapted to meet a number of more or less 

 remote contingencies, to achieve more or less far off aims, his brain 

 and mind display a corresponding complexity. Compare, for 

 example, a sea-anemone, whose consciously directed movements, 



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