6 Environment and Efficiency 



suggestion, of imitation, of hunger and want, have so long 

 been missing that when they again make their appearance 

 the instinct is either dead or controlled by habit. 



To refer again to the extreme importance of the child's 

 external inheritance. One hears so often the expression 

 that " so and so has inherited his mother's brilliance, or his 

 father's piety." This may be the case, but it is equally true 

 that the mother's mode of thought, the father's attitude 

 towards life, in fact the whole personality of that mother and 

 father, are commonly part of the child's external inheritance. 



Let us contrast this fair inheritance with that of the slum 

 child, who is said to inherit his mother's viciousness, his 

 father's criminal tendencies. Upon whose horizon does the 

 personality of the parents loom largest? Upon that of a 

 child growing up in the atmosphere which all good and 

 cultivated persons so insensibly create around them ; or 

 upon that of our little " hereditary criminal" who, during all 

 the early and most impressionable years of his life, lives, 

 eats, and sleeps in one poor room, which he shares with his 

 drunken and dissolute parents, and which is pervaded by that 

 atmosphere which they also so insensibly create around 

 them? 



There comes also the question whether the environment, 

 with its ensuing modifications, may not in course of time, 

 in a sense, induce innate variations. 



" Modifications that are effectively advantageous adaptive 

 responses in fact may have an indirect evolutionary im- 

 portance ; for they may serve as sheltering, life-preserving, or 

 welfare-furthering screens, until coincident variations in the 

 same direction have time and opportunity to establish them- 

 selves. Thus a modificational change may be gradually 

 replaced by a strictly variational and by hypothesis heritable 

 one." i 



Let us suppose a member of the Class H group to be 



1 J. A. Thomson, Heredity, p. 516. 



