188 Luck, or Cunning? 
natural selection appears from the next paragraph, on 
the third line of which we read, “‘ On the theory of natural 
selection the extinction of old forms,” &c. 
Again :— 
“ The theory of natural selection is grounded on the belief 
that each new variety and ultimately each new species, 
is produced and maintained by having some advantage 
over those with which it comes into competition ; and the 
consequent extinction of less favoured forms almost in- 
evitably follows ” (p. 320). Sense and consistency cannot 
be made of this passage. Substitute ‘‘ The theory of the 
preservation of favoured races in the struggle for life” for 
“The theory of natural selection” (to do this is only 
taking Mr. Darwin’s own synonym for natural selection), 
and see what the passage comes to. “‘ The preservation of 
favoured races ’’ is not a theory, it is a commonly observed 
fact ; it is not ‘‘ grounded on the belief that each new 
variety,’ &c., it is one of the ultimate and most elementary 
principles in the world of life. When we try to take the 
passage seriously and think it out, we soon give it up, and 
pass on, substituting ‘‘ the theory of descent ” for “ the 
theory of natural selection,’ and concluding that in some 
way these two things must be identical. 
Again :— 
“The manner in which single species and whole groups 
of species become extinct accords well with the theory of 
natural selection ’’ (p. 322). 
Again :— 
“ This great fact of the parallel succession of the forms 
of life throughout the world, is explicable on the theory of 
natural selection’ (p. 325). 
Again :— 
** Let us now look to the mutual affinities of extinct and 
living species. They all fall into one grand natural system ; 
and this is at once explained on the principle of descent” 
(p. 329). 
