GENERAL CONSIDERATIONS 183 



spring of the physically, intellectually, and morally weak, no 

 matter how many of the latter may marry, or how large be 

 their families. Comparatively few people are living to-day 

 who will have any descendants a thousand years from now, 

 and these are men of vigor and soundness, not only physi- 

 cally, but intellectually and especially morally, for nothing 

 will more surely bring a line of descendants to its close 

 than moral unsoundness. If the best among us should 

 marry the best, and generation after generation keep the 

 strain free from taint of weakness, real evolution in desirable 

 directions would be much more rapid. We need a more 

 wholesome ideal of character, so that we shall delight 

 in real strength, delight in men and women who in each 

 phase of their character have stamina and power. Strength- 

 ening this ideal and spreading it among men is the hope of 

 evolution into larger manhood. 



SOME GENERAL CONSIDERATIONS 



In closing this discussion of evolution let us emphasize 

 three general considerations. First, we should remember 

 that natural selection, the great factor in evolution, produces 

 adaptation to the conditions of the environment, and that 

 this does not by any means always imply an advance in com- 

 plexity of organization in plants and animals, or greater 

 development of the mind in animals. On the contrary, 

 degeneration, in the sense of simplification, often results 

 from the action of natural selection. To make this point 

 more vivid, let us look at an example of extreme degenera- 

 tion, so far as complexity of structure is concerned, and see 



