CHARLES ROBERT DARWIN. 131 
and quite different forms. In this respect we may truly say 
that in the domain of Zoology and Botany Darwin made 
the same progress as Lyell, his great countryman, in the 
domain of Geology. Both proved the uninterrupted con- 
nection of the historical development, and demonstrated a 
gradual transmutation of the different conditions succeeding 
one another. 
The special merit of Darwin, as I have already remarked 
in a preceding chapter, is twofold. In the first place, he has 
treated the Theory of Descent, put forth by Lamarck and 
Goethe, in a much more comprehensive manner, as a whole, 
and carried it out in a much more connected manner, than 
had been done by any one of his predecessors. Secondly, 
he has established the causal foundation of this Theory of 
Descent by the Theory of Selection, which is peculiarly his 
own ; that is, he has demonstrated the acting causes of the 
changes which the Theory of Descent simply stated, as facts. 
The Theory of Descent, introduced into Biology in 1809, by 
Lamarck, asserts that all the different species of animals 
and plants are descended from a single or some few most 
simple prototypes, produced by spontaneous generation. 
The Theory of Selection, established in 1859 by Darwin, 
shows us why this must be so; it points out the acting 
causes in a manner with which Kant would have been 
delighted, and indeed, in the domain of organic nature, 
Darwin has become the Newton whose advent Kant 
thought himself entitled prophetically to deny. 
Now, before we approach Darwin’s theory, it will perhaps 
be of interest to notice a few details as to the personal 
character of this great naturalist, as to his life, and the 
way in which he was led to form his doctrine. Charles 
