VI ABSENCE OF INSTINCT IN MAN 293 



and that from the nature of the case we are only able to 

 recognise its manifestations to a very limited degree, that 

 therefore our low estimate of these mental powers is based on 

 very little information. This limited extent of the mental 

 activities is compensated by definite instincts, whose operations 

 fulfil the essential requirements of the animal, and which are 

 so conspicuous as to attract our attention, while the rest of the 

 animal's actions due to mental faculties escape notice. But if 

 the explanation of instinct which I have given is recognised 

 as correct, even animals which act chiefly from instinct must 

 be described as " clever." 



The more manifold the demands upon an organism from 

 the outer world, in particular, the more they are subjected to 

 change of circumstances, so much the less can fixed instincts 

 be developed, so much the more will the brain have to be 

 developed, and to be capable of immediate and free response 

 to these external demands. Accordingly, in man there is but 

 little instinct, while voluntary action is very highly developed ; 

 but this is also connected with the fact that his body is 

 imperfectly adapted in many respects to external requirements. 

 Our senses, for example, as they exist are only sufficient 

 because their low degree of acuteness is compensated by the 

 high development of the brain, — this alone, for instance, has 

 enabled man to live under climatic conditions which, like 

 those of even our temperate zone, would not supply his 

 primary wants without special appliances. 



The slow and long development of the mental and bodily 

 powers of man is connected with this higher stage of mental 

 evolution which he has reached. Since man, in consequeoce 

 of the great complexity and the great variability of the 

 conditions under which he lives, cannot inherit experience, 

 therefore he must acquire his experience during his life, and 

 thus he attains independence at a relatively late period of 

 life. In this respect the anthropomorphous apes are nearest 



