h I have for short called
mechanical was not absent in the argument from design as stated before
Darwin. It seemed to have reference to a world conceived as fixed. It
pointed, not to the plastic capacity and energy of living matter, but
to the fixed adaptation of this and that organ to an unchanging place
or function.

Mr. Hobhouse has given us the valuable phrase "a niche of organic
opportunity." Such a phrase would have borne a different sense in
non-evolutionary thought. In that thought, the opportunity was an
opportunity for the Creative Power, and Design appeared in the
preparation of the organism to fit the niche. The idea of the niche
and its occupant growing together from simpler to more complex mutual
adjustment was unwelcome to this teleology. If the adaptation was
traced to the influence, through competition, of the environment, the
old teleology lost an illustration and a proof. For the cogency of the
proof in every instance depended upon the absence of explanation.
Where the process of adaptation was discerned, the evidence of Purpose
or Design was weak. It was strong only when the natural antecedents
were not discovered, strongest when they could be declared
undiscoverable.

Paley's favourite word is "Contrivance"; and for him contrivance is
most certain where production is most obscure. He points out the
physiological advantage of the _valvulae conniventes_ to man, and the
advantage for teleology of the fact that they cannot have been formed
by "action and pressure." What is not due to pressure may be
attributed to design, and when a "mechanical" process more subtle than
pressure was suggested, the case for design was so far weakened. The
cumulative proof from the multitude of instances began to disappear
when, in selection, a natural sequence was suggested in which all the
adaptations might be reached by the motive power of life, and
especially when, as in Darwin's teaching, there was full recognition
of the reactions of life to the stimulus of circumstance. "The
organism fits the niche," said the teleologist, "because the Creator
formed it so as to fit." "The organism fits the niche," said the
naturalist, "because unless it fitted it could not exist." "It was
fitted to survive," said the theologian. "It survives because it
fits," said the selectionist. The two forms of statement are not
incompatible; but the new statement, by provision of an ideally
universal explanation of process, was hostile to a