MAMMALS 65 



animal to play ? Will not even a tired puppy dart into 

 the water after a piece of wood ? Are not kittens sent 

 over and over again in pursuit of a rolling pebble ? Is 

 it really excess of energy that makes children play ? No. 

 It is not excess of energy ; a very little energy suffices. 

 Think of the scholar. He has worked hard all day 

 with his mind, yet he sits down to play cards in the 

 evening. Here he is devoting himself again to the 

 most complicated logical reasoning for the sake of the 

 game. 



How does the second principle stand ? Is the game 

 an imitation of real work, which man longs for, but has 

 no occasion to do ? 



This idea also must be abandoned when we reflect 

 again on the chief form of play — the play of young 

 animals. They have no thought whatever of serious 

 work ; how, then, can they feel a lack of it, and make 

 a pretence of it ? The young squirrels running unceas- 

 ingly up and down the tree, the young goats butting 

 each other with their heads, and so on, are not making 

 a pretence of doing real work, but are impelled by an 

 irresistible impulse. All animals have their character- 

 istic games even when they grow up in isolation, and so 

 have never seen the real work of their species. A 

 puppy that is early separated from its mother and 

 reared artificially will seize and shake the hem of a 

 coat in its characteristic way, just as a grown-up dog 

 does with cats, in order to break their necks. 



We have at last found the nucleus of play. It is an 

 impulse that caused it. Even in the games that imitate 

 the work of the adult, it is an impulse that urges the 



