THE KINGDOM OF MAN 239 



clues. This type of mind is in its finest expression rare, 

 but in its serviceable expression not uncommon, and 

 on its utilisation survival largely depends. 



No one need suppose that we are even for a moment 

 forgetting that social progress depends in part on feel- 

 ings of kinship, on generous good-will, and on the senti- 

 ment of solidarity, so characteristic of the Christian 

 religion. We are not for a moment forgetting the 

 impetus that may be given to any good cause by social 

 organisations sufficiently resolute ethically (as in regard 

 to slavery), or sufficiently enthusiastic (as in regard to 

 pacificism and women's suffrage), or sufficiently deter- 

 mined on lines of self-interest (as in the case of trade- 

 unions). But there are many problems which only 

 Science can solve. We need more knowledge and more 

 use of the knowledge we have. Knowledge is foresight, 

 and foresight is power. 



§ 7. Selection in Mankind 

 The Biological Theonj of Selection. — The method 

 of evolution which a study of living creatures reveals 

 is a method of trial and error, the sifting of organic 

 experiments. It is called the natural selection of 

 variations. Organisms are characteristically changeful 

 from generation to generation. Some of these changes 

 are advantageous and give their possessors a better 

 chance in life than their neighbours have. They have 

 ^ survival value.' Others are 2)ositively disadvantageous 

 and handicap their possessors. The theory of natural 

 selection is centred in the fact that the conditions of 



