DIFFERENTIATION OF SEXES 137 



ever farther differentiation of the sexes in habits and 

 character in opposite directions had a vast survival 

 value. 



It will be explained in the next chapter how this 

 unique division of the complete human race char- 

 acter into two sections, which was indispensable in 

 its early struggles with more powerful brute enemies 

 and competitors, became afterwards, when it was no 

 longer of any use whatever, perverted into a scourge 

 for the masses of mankind. This chapter will 

 further briefly deal with another phase of this 

 differentiation, viz., with the "mental and aesthetic" 

 complementariness of the sexes. 



The complete race life requires the possession of 

 considerable portions of both sets of sex traits, and 

 since in these latter days this differentiation is 

 almost universal in mankind, and the partial pos- 

 session of sufficient portions of both sets of qualities 

 by one individual is of very rare occurrence, there- 

 fore must many individuals of both sexes be neces- 

 sarily but imperfectly fitted for the full joy and 

 usefulness of the highest possible race life, if in this 

 present age they are without the comradeship of a 

 person of the other sex, and the consciousness of this 

 imperfection seems unavoidable, though often evi- 

 denced only by general unrest and dissatisfaction. 



This sensitiveness of each sex to its own deficien- 

 cies is necessarily associated with perception of the 

 proficiency of the other in these wished-for qualities. 

 That is to say, there exists in each sex a sense of its 



