SOCIAL AND WORLD ASPECTS 221 



physical configuration and ni mental activities, is 

 a palimpsest of cross-patterns and developmental 

 currents blended into a unified whole. But many 

 elements of the personality must also be determined 

 by mental differences based on inherited differences 

 in the nervous system. 



The Results of Crossing between Races. 



Eugenic wTiters differ, according to their social 

 and political bias, in the stress they lay upon a 

 democratic or an aristocratic society as the basis f(jr 

 eugenic improvement. This difficult question we 

 need not touch upon here, except to point out that the 

 methods of eugenic selection may differ somewhat 

 in the tw^o cases. The stratification of society in older 

 civilisations appears to be a natural process {cf. 

 Flinders-Petrie, 191 1), which has often been at first 

 acquiesced in rather than promoted by human arrange- 

 ments, though ultimately petrified and perpetuated 

 b}^ some form of caste. An aristocratic society might 

 be supposed to be composed of strains which wert- 

 more or less " pure lines " as regards their distin- 

 guishing characteristics, but this is seldom, if ever, 

 the case. The chief reason, of course, is that society 

 is so largely founded upon monetar}^ considerations, 

 and each class is therefore continually receiving- 

 recruits from other classes. In a population of real 

 pure lines, such as wheat or garden beans, the process 

 of selection for any given quality is simpler than in 

 a hybrid population, for it consists merely in finding- 

 one or a few individuals with the desired qualities, 

 and giving them the opportunity of increased pro- 

 pagation. 



On the other hand, an obvious weakness of an 

 aristocratic society from the point of view of eugenics 

 and heredity is the fact that while titles arc usually 



