SELECTION 167 



mind." ... "I use this term [' struggle for 

 existence '] in a large and metaphorical sense, 

 including dependence of one being on another, 

 and including (which is more important) not 

 only the life of the individual, but success in 

 leaving progeny." ... " Nature may be 

 compared to a surface on which rest ten 

 thousand sharp wedges touching each other, 

 and driven inward by incessant blows." . . . 

 41 It may be metaphorically said that natural 

 selection is daily and hourly scrutinizing 

 throughout the world the slightest varia- 

 tions." ... " Battle within battle must be 

 continually recurring with varying success; 

 and yet in the long run the forces are so nicely 

 balanced that the merest trifle would give the 

 victory to one organic being over another." 



What we wish to suggest is, that Darwin's 

 characteristic fundamental idea of the in- 

 tricacy of interrelations in the web of life, 

 lies below the idea of the struggle for existence, 

 and therefore below the idea of natural 

 selection. Unless we appreciate the funda- 

 mental natural history fact of the web of life, 

 we cannot rightly understand how slight 

 differences can be of critical moment in 

 determining survival. The entanglements are 

 so intricate that a slight variation may be of 

 survival -value to its possessor. 



