i. THE ORIGIN OF SPECIES 73 
‘The mode of investigation,” says Mr. Mill, ‘‘ which, from 
“the proved inapplicability of direct methods of observation and 
/ experiment, remains to us as the main source of the knowledge 
“We possess, or can acquire, respecting the conditions and laws of 
recurrence of the more complex phenomena, is called, in its 
most general expression, the deductive method, and consists of 
three operations : the first, one of direct induction ; the second, 
of ratiocination ; and the third, of verification.” 
—— 
_ Now, the conditions which have determined the 
existence of species are not only exceedingly com- 
plex, but, so far as the great majority of them are 
concerned, are necessarily beyond our cognisance. 
But what Mr. Darwin has attempted to do is in 
exact accordance with the rule laid down by —Mr. 
Mill ; he has endeavoured to determine certain 
| great f acts inductively, by c observation and_experi- 
ment; he has then rea asoned_from. the data thus 
ished ; and lastly, he | has tested the validity of 
his ratiocination by comparing his deductions with 
the observed facts of Nature. Inductively, Mr. 
& given way. Deductively, he desires to show 
that, if they arise in that way, the facts of distri- 
bution, development, classification, &c., may be 
accounted for, 7.c. may be deduced from their mode 
of origin, combined with admitted changes in 
physical geography and climate, during an inde- 
fmite period. And this explanation, or coinci- 
dence of observed with deduced facts, is, so far as 
it extends, a verification of the Darwinian view. 
There i is no fault to be found with Mr. Darwin’ s 
——— ne 
————— 
Darwin endeavours to prove that species arise in 
