SOCIAL SIGNIFICANCE OF HEREDITY 529 



One is tempted to speculate as to the possible sociological 

 interest of Mendel's Law, if it should be found to obtain in the 

 minglings of human races, but as yet we have not a sufficient 

 basis of fact. As we have seen, the inbreeding of hybrids of 

 peas, stocks, mice, etc., is followed by a splitting of the offspring 

 into true-breeding types like the two parents of the hybrids. 

 We may suggest that careful inquiry should be made as to the 

 results of inter-marriage among Eurasians, for if Mendel's Law 

 holds, there should be a sifting out of pure Asiatics and pure 

 Europeans, both probably more desirable than Eurasians, fine 

 mentally and physically as these often are. 



There are still some who find satisfaction in pointing out 

 that as human evolution is par excellence a psychical evolution, 

 biological conclusions on the question of inheritance are irre- 

 levant, since they are based on the study of measurable physical 

 qualities. But those who would press this point must deal 

 with Professor Karl Pearson's " Huxley Lecture " for 1903, 

 " On the Inheritance of the Mental and Moral Characters in 

 Man, and its Comparison with the Inheritance of the Physical 

 Characters " (Journ. Anthropological Institute , xxxii. pp. 

 179-237). His method was to obtain for upwards of one thousand 

 families impartial data as to fraternal resemblance in physical 

 and psychical characters in school-children. His argument 

 was, " If fraternal resemblance for the moral and mental char- 

 acters be less than, equal to, or greater than fraternal resem- 

 blance for the physical characters, we may surely argue that 

 parental inheritance for the former set of characters is less 

 than, equal to, or greater than that for the latter set of char- 

 acters." His conclusion, after many years of investigation, was 

 that " the degree of resemblance of the physical and mental 

 characters of children is one and the same," or, more 

 concretely, " we inherit our parents' tempers, our parents' 

 conscientiousness, shyness, and ability as we inherit their 

 stature, forearm, and span." The psychical characters are 



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