REFERENCE TO DARWIN. 7 
confused heads are often most thoroughly convinced of 
their own pre-eminence—on no subject do we so fre- 
quently hear superficial opinions, mostly condemnatory, 
and all evincing the grossest ignorance. 
I wish then to render the reader able to survey 
the whole ramified and complicated problem of the 
doctrine of Descent, and its foundation by Darwin, and 
to enable him to understand its cardinal points. But 
we must first dispose of a preliminary question of uni- 
versal importance and special significance, which is 
frequently ignored by philosophical and theological 
opponents, that is, the question of the limits of the in- 
vestigation of nature. Forif it were an established prin- 
ciple that the mystery of the living is different from 
that of the non-living, that the former might be disclosed, 
but that the latter is shrouded in a veil which never can 
be raised, as is even now so frequently asserted, then, 
indeed, all research directed towards the comprehension 
of life would be utterly vain and hopeless. 
But if the possibility of investigating life and its origin 
be not opposed by any @ priord scruples, still more, if 
the limits of investigation and knowledge, which un- 
doubtedly exist, are no other for animate nature than 
for the inanimate world of. matter, we may venture to 
approach our task. ‘This will be most adequately effected 
by making ourselves somewhat familiar with the object 
of the doctrine of Descent, restricting ourselves, however, 
to the animal world. -If I say then that we must obtain a 
foundation for the theory of derivation or descent, for the 
doctrine of the gradual and direct development of the 
higher and now-existing organisms from lower ancestral 
forms—in short, for the doctrine of the continuity of 
