Instinct and Intelligence 69 



represents a tendency to brain variation in the direction 

 of fixed connections between certain sense-centres and 

 certain groups of coordinated muscles. This tendency is 

 embodied in the white matter and the lower brain centres. 

 The other represents a tendency to variation in the direc- 

 tion of alternative possibilities of connection of the brain 

 centres with the same or similar coordinated muscular 

 groups. This tendency is embodied in the cortex of the 

 hemispheres. I have cited 'thumb-grasping' because we 

 may see in the child the anticipation, by intelligence and 

 imitation, of the use of the thumb for the adaptation 

 which the simian probably gets by instinct or accident, 

 and which I think an isolated and weak-minded child, say, 

 would also come to acquire by instinct or accident when 

 his apparatus became sufficiently matured. 



§5. Instinct and Intelligence 



IV. Finally there are two general bearings of the 

 position taken above regarding the place and function of 

 intelligence and imitation which may be briefly noted. 



I. We reach a point of view which gives to organic 

 evolution a sort of intelligent direction after all ; for of all 

 the variations tending in the direction of an instinct, but 

 inadequate to its complete performance, only those will be 

 supplemented and kept alive which the intellige7ice ratifies 

 and uses for the animaVs individual accommodations. The 

 principle of selection applies strictly to the others or to some 

 of them. So natural selection eliminates the others ; and 

 the future development of instinct must at each stage of a 

 species' evolution be in the directions thus ratified by intel- 

 ligence. So also with imitation. Only those imitative 



