Preface vii 



and Mendelism, foi" both now transcend any treatment which fails to 

 approach them with adequate mathematical knowledge. 



If this view be a true view of the evolution of biological thought 

 in the near future, then any comparison of the relative greatness of the 

 two men becomes superficial. Darwinism needs the complement of 

 Galtonian method before it can become a demonstrable truth ; it 

 I'equires to be supplemented by Galtonian enthusiasm before it can 

 exei'cise a substantial influence on the conscious direction of race 

 evolution. Man has been directly endeavouring for a few thousand 

 years to imj^rove himself by improving his environment. Galton's 

 lesson — over and over again disregarded by those who profess to be his 

 disciples — was that little could be achieved this way, that the primary 

 method to elevate the race was to insure that its physically and 

 mentally abler members, not only had the unrecognised advantage of 

 natural selection in their favour, but were directly and consciously 

 encouraged to be fertile by the state. If my view be correct, Erasmus 

 Darwin planted the seed of suggestion in questioning whether adapta- 

 tion meant no more to man than illusti^ation of creative ingeniiity ; 

 the one grandson, Charles Darwin, collected the facts which had to be 

 dealt with and linked them together by wide-reaching hypotheses; the 

 other grandson, Francis Galton, provided the methods by which they 

 could be tested, and saw with the enthusiasm of a prophet their 

 application in the future to the directed and self-conscious evolution of 

 the human race. It is unprofitable to discuss relative gi-eatness, and 

 in this work I have made no attempt to do so. I see one family which 

 has done much for our national worth, and eveiy fact which bears on its 

 history and its characteristics is of interest to us all. Those who know 

 the real history of the one occasion on which Galton and Darwin 

 disagreed know how loyal Galton was to Darwin — loyal with a loyalty 

 far rarer to-day. Galton would not have wished me to put him in 

 the same rank as his master, but the reader who follows my story to 

 the end may possibly see that the ramifications of Galton's methods 

 are producing a renascence in innumerable branches of science, which 

 will be as epoch-making in the near future as the Darwinian theory of 

 evolution was in biology from 1860 to 1880, and which has encountered 

 and will encounter no less bigoted opposition from both the learned and 

 the lay. To work for that Galtonian renascence has been the writer's 

 main aim in life as it was also that of his chief colleague and friend — 

 W. F. R. Weldon. I can only hope that these volumes will contribute 



