XV 
DARWINISM APPLIED TO MAN 
463 
here, and a reference to it has been introduced only to complete 
the sketch of Mr. Darwin’s view of the continuity and gradual 
development of all human faculties from the lower animals up 
to savages, and from savage up to civilised man. The point 
to which I wish specially to call attention is, that to prove 
continuity and the progressive development of the intellectual 
and moral faculties from animals to man, is not the same as 
proving that these faculties have been developed by natural 
selection; and this last is what Mr. Darwin has hardly 
attempted, although to support his theory it was absolutely 
essential to prove it. Because man’s physical structure has been 
developed from an animal form by natural selection, it does not 
necessarily follow that his mental nature, even though developed 
pari passu with it, has been developed by the same causes only. 
To illustrate by a physical analogy. Upheaval and depres¬ 
sion of land, combined with sub-aerial denudation by wind 
and frost, rain and rivers, and marine denudation on coast¬ 
lines, were long thought to account for all the modelling of 
the earth’s surface not directly due to volcanic action ; and 
in the early editions of Lyell’s Principles of Geology these 
are the sole causes appealed to. But when the action of 
glaciers was studied and the recent occurrence of a glacial epoch 
demonstrated as a fact, many phenomena—such as moraines 
and other gravel deposits, boulder clay, erratic boulders, 
grooved and rounded rocks, and Alpine lake basins—were seen 
to be due to this altogether distinct cause. There was no breach 
of continuity, no sudden catastrophe; the cold period came 
on and passed away in the most gradual manner, and its effects 
often passed insensibly into those produced by denudation or 
upheaval; yet none the less a new agency appeared at a 
definite time, and new effects were produced which, though 
continuous with preceding effects, were not due to the same 
causes. It is not, therefore, to be assumed, without proof 
or against independent evidence, that the later stages of an 
apparently continuous development are necessarily due to the 
same causes only as the earlier stages.. Applying this argu¬ 
ment to the case of man’s intellectual and moral nature, I 
propose to show that certain definite portions of it could not 
have been developed by variation and natural selection alone, 
and that, therefore, some other influence, law, or agency is 
