Heredity in Man. t>oZ 



If the need become habitual, the animal may, so to speak, 

 instruct his banker to set aside a specific sum to meet this 

 need as often as it arises. But this arrangement is a purely 

 individual matter, and no wise dictated by the terms of 

 the bequest. The human infant inherits a certain number 

 of specific drafts ; but the bulk of his inheritance is an 

 invaluable legacy of innate capacity, the specific applica- 

 tion of which is in his own hands, under the conditions of 

 his social environment, and under the guidance of his 

 parents and guardians. What we must consider, then, 

 is whether there is any such marked increase of innate 

 capacity as may fairly be ascribed to the direct transmis- 

 sion of acquired increments of faculty, and whether the 

 innate susceptibilities are specialized through the effects 

 of such transmission. The adequate discussion of these 

 questions would require a separate treatise ; all that can 

 here be attempted is an outline of what would seem to be 

 the more salient features in a field of inquiry which the 

 multiplicity of details renders extremely complicated. 



In considering these questions, we must take up the 

 thread of the discussion which occupied most of the 

 chapter on the Relation of Organic to Mental Evolu- 

 tion. The conclusions there reached were, it will be 

 remembered, as follows. Mental evolution, as such, is 

 dependent upon individual choice ; throughout animal life 

 it is subservient to organic needs, and is conditioned and 

 controlled by natural selection ; continuity of mental de- 

 velopment in the race is rendered possible by organic 

 heredity ; and progress in mental development is pre- 

 dominantly due to the combined effects of heredity and 

 natural selection acting upon organisms possessed of 

 mental powers. 



We must be particular to note the subservient position 

 which mental evolution holds in the life of animals. What 



