y natural selection. _How_
much we cannot say--probably never shall be able to say; for even Mr.
Darwin himself does not doubt that other causes besides that of natural
selection have assisted in the modifying of specific types. For the
sake of simplicity, however, I shall not go into this subject; but shall
always speak of natural selection as the only cause of organic
evolution. Let us, then, weigh the evidence in favour of organic
evolution. If we find it wanting, we need have no complaints to make of
natural theologians of to-day; but if we find it to be full measure,
shaken together and running over, we ought to maintain that natural
theologians can no longer adhere to the arguments of such writers as
Paley, Bell, and Chalmers, without deliberately violating the only
logical principle which separates science from fetishism.

To avoid misapprehension, however, I may here add that while Mr.
Darwin's theory is thus in plain and direct contradiction to the theory
of design, or system of teleology, as presented by the school of writers
which I have named, I hold that Mr. Darwin's theory has no point of
logical contact with the theory of design in the larger sense, that
behind all secondary causes of a physical kind, there is a primary cause
of a mental kind. Therefore throughout this essay I refer to design in
the sense understood by the narrower forms of teleology, or as an
_immediate_ cause of the observed phenomena. Whether or not there is an
_ultimate_ cause of a psychical kind pervading all nature, a _causa
causarum_ which is the final _raison d'etre_ of the cosmos, this is
another question which, as I have said, I take to present no point of
logical contact with Mr. Darwin's theory, or, I may add, with any of the
methods and results of natural science. The only position, therefore,
which I here desire to render plain is that, if the doctrine of
evolution is seen to be established by sufficient evidence, and
therefore the causes which it sets forth are recognised as adequate to
furnish a scientific explanation of the results observed, then the
facts of organic nature necessarily fall into the same logical category,
with reference to any question of design, as that of all or any other
series of facts in the physical universe.

This being understood, I shall now proceed to render an epitome of the
evidence in favour of organic evolution, and I shall do so by
classifying the arguments in a way tending to show their d