326 Heredity. 



portant to males should vary more than a part which is 

 important to females. 



We are thus able to understand the great difference in 

 the males of allied species, the difference between the 

 adult male and the female or young, and the great diver- 

 sity and variability of secondary male characters, and we 

 should expect to find, what actually is the case, that 

 among the higher animals, when the sexes have long been 

 separated, the males are more variable than the 

 females. 



In the chapter on the intellectual differences between 

 men and women, I have shown that those philosophical 

 writers who have devoted especial attention to the subject 

 have reached conclusions which are exactly what our hy- 

 pothesis would lead us to expect. The view that the 

 male mind is the progressive element in intellectual 

 development, and the female mind the conservative ele- 

 ment, accords with the views which have been generally 

 recognized and accepted by the common consent of man- 

 kind, and although our opinions upon this very compli- 

 cated subject may possibly be very far from accurate, a 

 certain conformation to the demands of our hypothesis 

 cannot be denied. 



The facts relating to hybrids, to variation, to the 

 secondary sexual characters of animals, and to the intel- 

 lectual differences between men and women, which are 

 stated at some length in chapters V. to IX., cover a very 

 wide and diversified field, and any law which groups and 

 explains them all is certainly worthy of careful examina- 

 tion. The most candid review which I am able to give 

 to the evidence from all these sources, convinces me that 

 the explanation which I have offered in this book is at 

 least a step in the right direction, and that whether it be 

 accepted in its present form or not, it does serve to en- 



