Intelligent Direction and Social Progress 145 



It was also intimated, in the earlier section, that when 

 the intelligence once comes to play an important part in 

 the accommodations of the individuals, then we should 

 expect that it would be the controlling factor in race-prog- 

 ress. This happens in two ways which may now allow of 

 brief statement. 



I. The intelligence represents the highest and most 

 specialized form of accommodation. With it goes, on the 

 active side, the great fact of volition, which seems to spring 

 directly out of the imitative impulse of the child. It there- 

 fore becomes the goal of organic fitness to secure the best 

 intelligence. On the organic side, intelligence is correlated 

 with plasticity in brain structure. Thinking and willing 

 stand for the opposite of that fixity of structure and direct- 

 ness of reaction which characterize the life of instinct. 

 Progress in intelligence, therefore, represents readiness 

 for much acquisition, together with very little congenital 

 instinctive equipment. 



It is easy to see the effects of this. The intelligence 

 secures the widest possible range of personal adjustments, 

 and by so doing widens the sphere of organic selection, so 

 that the creature which thinks has a gene^'al screen from 

 the action of natural selection. The struggle for existence, 

 depending upon the physical qualities on which the animals 

 rely, is in some degree done away with. 



This means that with the growth of intelligence, creatures 

 free themselves more and more from the direct action of nat- 

 ural selection. Variations of a physical kind come to have 

 within limits an equal chance to survive. Progress then de- 

 pends on the one kind of variation which represents improved 

 intelligence — variations in brain structure with the organic 

 correlations which favour them — more than on other kinds. 



