THE INSTINCTS AND THE ACQUIREMENTS OF MAN 241 



which useful mental acquirements are made. The young 

 caterpillar, which is almost if not quite incapable of making 

 mental acquirements, is neither curious nor imitative. The 

 young monkey is both, as is the young human being to a yet 

 greater extent. The instinct of curiosity impels the individual 

 to acquire a knowledge of the world round him as a remedy 

 for his deficiencies of instinct. The imitative instinct impels 

 him to copy his elders and so acquire useful traits. This 

 instinct lies at the foundation of all animal society which is 

 not on a purely instinctive basis. The young human being 

 not only learns to walk and speak by imitation, but acquires 

 in a general way the whole tone of the society in which he is 

 reared. Hence the importance of a right choice of com- 

 panions for him. Adults are less curious and imitative than 

 children ; for, as development nears completion, and a 

 sufficient number of useful mental traits, and an adequate 

 working knowledge of the environment has been acquired, 

 these instincts become of less and less value, and undergo 

 atrophy. Human environment is so complex and variable, 

 however, and man's power of making mental acquirements is 

 so great, that they do not lose all value. They persist to 

 some extent even in the oldest individual. Hence the gossip's 

 inquisitiveness and the scholar's industry. Hence the sway 

 of fashion, and the spreading infection of enthusiasm. All 

 research too is prompted by the instinct of curiosity, all 

 sympathy by the imitative instinct. 



400. Among man's surviving instincts none is more im- 

 portant nor presents features of greater interest than the love 

 of play. Young animals of a purely instinctive species, most 

 insects for example, never sport. Their lives are entirely 

 business-like. Play would be useless to them, since their 

 bodies develop without exercise and their minds without 

 experience. Young ants are said to play, and the statement 

 is very probable, for their power of making mental acquire- 

 ments is very great. But as regards most other insects, 

 particularly those which in youth lead solitary lives, only 

 the adults indulge in a sort of play, or rather dance, while 

 displaying their sexual attractions. Thus during the late 

 summer we see the love-dance of gnats ; and often house-flies 

 from the same cause sport in the centre of a room. The 

 young of the higher animals, however, are full of play. The 

 kid, the kitten, the puppy, the young monkey, and the young 

 elephant spend their lives in eating, sleeping, and especially 

 in sporting. The higher the animal the more capable of 

 making physical and mental acquirements, the more sportive 



