THE KINGDOM OF MAN 241 



relatively rare. The established system of inter-relations 

 has often a progressive influence ; when the inter- 

 relation is parasitism the influence is retrogressive. 



Selection in Mankind. — In the early days Man was 

 very thoroughly in the sieve of Natural Selection and 

 also in the grip of Natural Forces which destroyed 

 indiscriminately without sifting. The serpent bit his 

 heel, the poisonous thorns cut his skin, the beasts of 

 prey devoured him, the floods drowned him. But as 

 age succeeded age and man's brain grew, his mastery 

 of Nature increased. He cared less and less for what 

 serpent or thorn, wild beast or flood could do ; his 

 struggle for existence changed in tone and colour. 

 Civilisation has meant in part a throwing off of the 

 yoke of Natural Selection. Even famine and pestilence 

 can be controlled. 



We have recalled the modern achievements by which 

 diseases like smallpox, diphtheria, typhoid fever, malaria, 

 and others have been conquered. Why has Man 

 with magnificent patience persisted in this campaign 

 against disease ? Partly, of course, because of self- 

 preservative instincts, because he is a sympathetic 

 being, because he does not like to be beaten, but partly 

 also because he discerned that many of the diseases 

 that beset him are not sifting agencies, but indiscriminate 

 in their operation, as in the case of those mentioned 

 above. Sifting is hard to bear, but thinning without 

 sifting is hideously wasteful. In the language of one of 

 Man's familiar ideals, "it is not good business." 



There is evidence of sonie natural selection still in 



