THE PSYCHOLOGY OF ANIMAL PLAY. 301 



are acted out, are outside the sphere of the animal psy- 

 chologist, but he is interested in those directly connected 

 with the imitative arts. Since Lange, both here and 

 in a later article, has found conscious self-deception also 

 in the other arts,* I think it is admissible to include it 

 among the other plays, always with the proviso that con- 

 sciousness of the sham character of the act is not neces- 

 sarily present, but may be. The feature common to all 

 animal play is that instinct is manifested without seri- 

 ous occasion. Now, when the animal knows that there 

 is no serious occasion, and yet goes on playing, we 

 have conscious self-deception. It seems to me that this 

 is the case with most of the play of animals, though 

 not with equal certainty; perhaps least of all in imita- 

 tive play. If we take the dog's play with a stick, for 

 instance, as an example of conscious mock activity, we 

 see that there is no imitation in it, because it is done 

 without a model, f 



Glancing over the various kinds of play, can we 

 say that the animal pretends to follow a serious aim 

 when he merely experiments, as when he runs about 

 in a movement play, or springs after a block of wood as 

 if it were prey, or scuffles with his comrade, or amuses 

 himself with building, or treats a young animal of some 

 other kind like a doll, or playfully imitates another, or 

 displays curiosity, or practises his courtship arts? Now, 

 it is evident that the probability of conscious make- 

 believe is a variable quantity in these cases. It seems 

 to be quite certain in the frequently repeated hunting 

 and fighting games, less so in experimentation, move- 



* Ibid., p. 21. 



f [It is in connection with this question that I have made the 

 suggestion {Science, February 26, 1897) stated above in my preface, 

 p. x.— J. Mark Baldwin.] 



