250 THE STRUGGLE FOIi THE LIFE OF OTHERS. 



important, but of the very highest imaginable impor 

 tance.&quot; 1 



These views may be each true ; and probably, in a 

 measure, are ; but the fact remains that the later 

 psychical implications of sex are of such transcendent 

 character as to throw all physical considerations into 

 the shade. When we turn to these, their significance 

 is as obvious as in the other case it was obscure. 

 This will appear if we take even the most dis 

 tinctively biological of these theories that of Weis- 

 mann. Sex, to him, is the great source of variation in 

 Nature, in plainer English, of the variety of organisms 

 in the world. Now this variety, though not the main 

 object of sex, is precisely what it was essential for 

 Evolution by some means to bring about. The first 

 work of Evolution always is, as we have seen, to 

 create a mass of similar things atoms, cells, men 

 and the second is to break up that mass into as many 

 different kinds of things as possible. Aggregation 

 masses the raw material, collects the clay for the pot 

 ter ; differentiation destroys the featureless monotonies 

 as fast as they are formed, and gives them back in 

 new and varied forms. Now if Evolution designed, 

 among other things, to undertake the differentiation of 

 Mankind, it could not have done it more effectively 

 than through the device of sex. To the blending, or to 

 the mosaics, of the different characteristics of father 

 and mother, and of many previous fathers and 

 mothers, under the subtle wand of heredity, all the 

 varied interests of the human world is due. When 

 one considers the passing on, not so much of minute 

 details of character and disposition, but of the domi- 

 1 Biological Memoirs, p. 281. 



