Febeuaey 26, 1897.] 



SCIENCE. 



349 



acter which distinguishes them from other 

 specialized instinctive actions. They are dis- 

 tinguished as play actions, not simply as ac- 

 tions. This diiHculty really touches the kei'nel 

 of the matter, and serves to raise the question 

 of the relation of imitation to play ; for imita- 

 tion presents exactly the same conditions — a 

 general instinct to imitate, which is not ex- 

 hausted in the particular actions which are per- 

 formed by the imitation. I shall remark on the 

 solution of it below, in speaking of Professor 

 Groos' psychology of play. It will be interesting 

 to see how he treats this problem in his prom- 

 ised work on the Spiele der Menschen; for the 

 imitative element is very marked in children's 



Other points of great interest in this biological 

 part are the great emphasis which Groos finds 

 it necessary to put on 'tradition,' instruction, 

 imitation, etc., in young animals, even in en- 

 abling them to come into possession of their 

 natural instincts ; in this the book tends in the 

 same direction as the new volume of Professor 

 C. Lloyd Morgan. A.gain, there is a remarkably 

 acute discussion of Darwin's Sexual Selection, 

 which the author finally accepts in a modified 

 form by saying that the female's selection is not 

 necessarily conscious, but that she has an in- 

 herited susceptibility to certain stimulating 

 colors, movements, etc. , in the male. It is not 

 so much intelligence on her part as increased 

 irritability in the presence of certain visual and 

 other stimulations. *Over against the charms 

 of the male he sets the reserve or reluctance 

 (Sprodigkeit) of the female, which has to be 

 overcome and which is an important check and 

 regulator at the mating time. Again, the im- 

 perfect character of most instincts is empha- 

 sized, and the interaction with imitation and 

 intelligence. He finds a basis for the inverse 

 ratio between intelligence and instinct is an 

 animal's equipment on natural selection princi- 

 ples, i. e., the more intelligence develops the 

 less does natural selection bear on special in- 

 stincts, and so they become broken up. 



* ' Sexual ' is thus referred "back to ' natural ' selec- 

 tion (p. 274), although the direct results of such prefer- 

 ential mating would still seem to give very ' determi- 

 nate ' variations for natural selection to work upon 

 {Cf. Science, Nov. 23, 1896, p. 726). 



Finally, I should like to suggest that a possible 

 category of ' Social Plays ' might be added to 

 Groos' classification — plays in which the utility 

 of the play instinct seems to have reference 

 to social life as such. Possibly in such a 

 category it might be possible to place certain of 

 the animals' performances, which seem a little 

 strained under the other heads — for example, 

 those performances in which the social function 

 of communication is exercised early in life. A 

 good deal might be said also in question of the 

 author's treatment of ' Curiosity ' {Neugier). 

 He makes curiosity a function of the attention, 

 and finds the restless activity of the attention a 

 play function, which brings the animal into 

 possession of the details of knowledge before 

 they are pressed in upon him by harsh experi- 

 ence. My criticism would be that attention 

 does not fulfil the requirements of the author's 

 psychological theory of play, as indicated 

 below. 



Turning now to the interesting question of 

 the psychological theory, we find it developed, 

 as it would have to be, in a much more theo- 

 retical way. The play consciousness is funda- 

 mentally a form of ' conscious self-illusion' (311 

 IT) — bewusste Selbsttauschung. It is just the dif- 

 ference between play activity and strenuous 

 activity that the animal knows, in the former 

 case, that the situation is not real, and still 

 allows it to pass, submitting to a pleasant sense 

 of illusion. It is only fair to say, however, that 

 Herr Groos admits that in certain definite in- 

 stinctive forms of play this criterion does not 

 hold ; it would be difficult to assume any consci- 

 ousness of self-illusion in the fixed courting and 

 pairing plays of birds, for example. The same 

 is seen in the very intense reality which a 

 child's game takes on sometimes for an hour at 

 a time. Indeed, the author distinguishes four 

 stages in the transition from instincts in which 

 the conscious illusion is absent, to the forms of 

 play to which we can apply the phrase 'Play ac- 

 tivity' in its true sense, i. e., that of Scheinthiltig- 

 keit (298 f). The only way to reconcile these po- 

 sitions that I see is to hold that there are two dif- 

 ferent kinds of play : that which is not psycho- 

 logical at all, i. e., does not show the psycho- 

 logical criterion at all, and that which is psy- 

 chological as Scheinthdtigkeit. Herr Groos does 



