vitality or impair its blood. Doubtless a 

 dozen wars may do all this. The difference 

 is one of degree alone ; I wish only to point 

 out the tendency. That the death of the 

 strong is a true cause of the decline of nations 

 is a fact beyond cavil or question. The " man 

 who is left *' holds always the future in his 

 grasp. One of the great books of our cen- 

 tury will be some day written on the selec- 

 tion of men, the screening of human life 

 through the actions of man and the oper- 

 ation of the institutions men have built up. 

 It will be a survey of the stream of social 

 history, its whirls and eddies, rapids and 

 still waters, and the effect of each and all of 

 its conditions on the heredity of men. The 

 survival of the fit and the unfit in all degrees 

 and conditions will be its subject-matter. 

 This book will be written, not roughly and 

 hastily, like the present fragmentary essay, 

 the work of one whose business of life runs 

 in wholly different lines. Still less will it be 

 a brilliant effort of some analytical imagi- 

 nation. It will set down soberly and statis- 

 tically the array of facts which as yet no one 

 possesses; and the new Darwin whose work 



The 



Human 



Harvest 



["9] 



