17 



of Species" show plainly the scope of his 

 work, and that it was not so much the principle 

 of natural selection as the mutability of species 

 which he wished to establish on a firm and 

 lasting basis. He says: 



"Although much remains obscure, and will 

 long remain obscure, I can entertain no doubt, 

 after the most deliberate and dispassionate 

 judgment of which I am capable, that the view 

 which most naturalists until recently entertain 

 ed, and which I formerly entertained namely, 

 that each species has been independently cre 

 ated is erroneous. I am fully convinced that 

 species are not immutable." 



This, then, was the end and aim of Darwin's 

 work to show that the barriers which were 

 supposed to divide species from one another 

 were not insurmountable that species are not 

 immutable. The principle of natural selection, 

 it is true, entered into his theory as a predom 

 inating factor, but its place was always second 

 ary and subordinate; its importance was great, 

 in his estimation, but always subsidiary. This 

 is evident from the words which follow those 

 above quoted, where he says : 



