Modification by Experience 305 



evidences of memory ideas should appear in animals 

 which like the raccoon and the monkey are dexterous, 

 able to use their paws for movements more complex and 

 refined than those of locomotion. The supreme develop- 

 ment of ideas comes in the mind of the animal which has 

 not merely hands, but vocal organs, so that an infinite 

 variety of delicate and complicated movements can be 

 anticipated, and can form the basis of memory ideas. 



Thirdly, one of the conditions of the anticipation of a 

 movement appears to be attention to it when it is originally 

 performed. In order to remember a movement, we must 

 have paid attention to the sensations which its performance 

 occasions, to the way it feels to make the movement. And 

 one condition for attention to the way a movement feels 

 is being comparatively safe from external dangers when 

 the movement is made. An animal under ordinary condi- 

 tions of wild life has very little attention to spare for his 

 own movements. It would thus seem as though one 

 requirement which must be fulfilled if anticipated move- 

 ments are to play an important part in a creature's experi- 

 ence were that the animal should, for a time at least, be 

 set free from the pressure of the practical hand-to-hand 

 struggle for the means of existence, and thus enabled in 

 safety to attend to its own movement sensations. Animal 

 play, at first thought, offers an instance of such liberation 

 from practical necessities. But as Groos has shown, 

 animal play is not so unpractical as it looks (270). It is 

 simply the exercise of the same instincts upon which in 

 other circumstances the animal's welfare depends. The 

 attention is absorbed in external objects quite as much 

 in play as in the actual chase or warfare. The kitten 

 watches the string, for which she has no practical use, 

 as intently as she watches the bird for which she does 



