PLAY 63 



graven in all details into the brain as they would necessarily have to 

 be in case they were called upon to function in earnest before being 

 trained ; they therefore make their appearance already in youth and 

 are thus enabled by means of practice to be developed while there is 

 yet time for preparation." (p. 7-4.) 



"Animals can not be said to play because they are young and 

 frolicsome, but rather they have a period of youth in order to play." 

 "Youth probably exists for the sake of play."^ The play of young 

 animals, according to Groos, has its origin in the fact that certain 

 very important instincts appear at a time when the animal does not 

 seriously need them. The utility of the exercise of these instincts in 

 the form of play is incalculable, inasmuch as it affords for some of the 

 more important duties of life an invaluable preparation. It paves the 

 way from blind heredity to adaptable and adjustable intelligence. It 

 is especially useful in this respect, since natural selection tends to 

 weaken the force of instinct and aids more and more the development 

 of intelligence as a substitute for it. Thus natural selection favors 

 those animals which play.^ 



The theory of Groos lays too much stress upon instinct. Many 

 play activities are denominated as instinctive by Groos which are 

 really adult ancestral activities handed down by social tradition from 

 generation to generation. Many of them, it is quite true, grow out 

 of or were grafted on to native or congenital impulses; but many 

 again are manifestations of habits acquired de novo, the plasticity of 



'Groos, The Play of Animals, p. 75. 



'The plays of animals are classified as follows: 



1. Experimentation. 



2. Movement plays. 



3. Hunting plays: 



a. With real living: prey. 



b. With living mock prey. 



c. With lifeless mock prey. 



4. Fighting plays: 



a. Teasing. 



b. Tussling among young animals. 



c. Playful fighting among grown animals. 



5. Love plays: » 



a. Among young animals. 



b. Rhythmical movemcTits. 



c. The display of beautiful and unusual colors and forms. 



d. The production of calls and notes. 



e. The coquetry of the female. 



6. Constructive arts. 



7. Nursing plays. 



8. Imitative plays. 



9. Curiosity 



