EDITOR'S PREFACE. V 



which are developed for their utility. It is very near, 

 in its origin and function, to the instinct of imitation, 

 but yet they are distinct (a word more below on the rela- 

 tion between play and imitation). Its utility is, in the 

 main, twofold : First, it enables the young animal to ex- 

 ercise himself beforehand in the strenuous and necessary 

 functions of its life and so to be ready for their onset; 

 and, second, it enables the animal by a general instinct to 

 do many things in a playful way, and so to learn for itself 

 much that would otherwise have to be inherited in the 

 form of special instincts ; this puts a premium on intelli- 

 gence, which thus comes to replace instinct (p. 71). 

 Either of these utilities, Professor Groos thinks, would 

 insure and justify the play instinct; so important are 

 they that he suggests that the real meaning of infancy 

 is that there may be time for play (see his preface). 

 This general conception of play has been set forth by 

 other writers; but Professor Groos works it out in this 

 book in a way which attaches his name permanently to it. 



It is especially in connection with this latter func- 

 tion of play, I may add, that the instinct to imitate cornea 

 in to aid it. Imitation is a real instinct, but it is not 

 always playful; play is a real instinct, but it is not 

 always imitative. There is likely, however, to be a great 

 deal of imitation in play, since the occasion on which a 

 particular play-function develops is often that which also 

 develops the imitative tendency as well — i. e., the actual 

 6ight or hearing of the acts or voices of other animals. 

 Moreover, the acquisition of a muscular or vocal action 

 through imitation makes it possible to repeat the same 

 action afterwards in play. 



It is only a step, therefore, to find that imitation, 

 as an instinct, has to have ascribed to it, in a measure, 

 the same race utility as play — that of going before the 



