BIOLOGICAL PHILOSOPHY 419 



The findings on identical twins reared apart check pretty well with other 

 studies on the relative contributions of heredity and environment to indi- 

 vidual differences in intelligence in the general run of our population. Of 

 course, nineteen pairs collected by Newman and one by Muller is a number 

 woefully inadequate for statistical validity, but this inadequacy is typical 

 of the present state of the science of man. 



I II 



In the field of genetics, the marvelous advances of the past forty years 

 have been largely limited to the genetics of plants and animals. For some 

 reason, human genetics has been largely neglected in this country compared 

 to what has been done by Fisher, Haldane and Hogben, in England, and 

 by Verschuer and others in Germany. There is almost no knowledge of 

 genetic factors in normal variations in general qualities, such as intelli- 

 gence, character or susceptibility to disease. Important work has been done 

 on blood groups. A considerable number of infrequent abnormalities are 

 known to be due to genetic factors, and in some cases the mode of in- 

 heritance is known. Research work on genetic factors in feeble-mindedness 

 and in mental disease is almost all in the future. Nevertheless, there are 

 many signs of an aroused interest in the medical profession and a new 

 recognition of their responsibiUty for preventing the spread of serious 

 hereditary defects. 



Ultimately, scientific knowledge in regard to the part played by genetic 

 factors in causing individual differences, and further research on the in- 

 heritance of different genetic factors, may make possible measures that 

 would tend to discourage the reproduction of inferior genetic strains and 

 encourage the reproduction of those above the average. 



Thus, scientific knowledge of the relative parts played by heredity and 

 by environment in developing individual differences may become a valua- 

 ble tool for improving human qualities, first on the environmental side 

 through changes in education and ultimately through raising the average 

 hereditary level. 



IV 



Anthropology has made at least one important contribution to the 

 American point of view by showing the extent to which culture patterns 

 are fixed by the social environment with little regard to the type of people 

 involved. The whole concept of race has undergone a violent transforma- 

 tion in the past fifteen years. It is said that Hitler during the two years he 

 spent in jail before coming to power read widely in what were then sup- 

 posed to be scientific books dealing with race. They were not scientific in 

 our present definition of the term: they were the German analogies of 

 Madison Grant's "Decline of the Great Race," which was having a vogue 

 in this country at that time. Modern research of a more scientific sort denies 



