ch is seen either too obviously or with too much difficulty. Nothing
is worth doing or well done which is not done fairly easily, and some
little deficiency of effort is more pardonable than any very perceptible
excess, for virtue has ever erred on the side of self-indulgence rather
than of asceticism.

According to Buffon, then--as also according to Dr. Darwin, who was just
such another practical and genial thinker, and who was distinctly a pupil
of Buffon, though a most intelligent and original one--if an organ after
a reasonable amount of inspection appeared to be useless, it was to be
called useless without more ado, and theories were to be ordered out of
court if they were troublesome. In like manner, if animals breed freely
_inter se_ before our eyes, as for example the horse and ass, the fact
was to be noted, but no animals were to be classed as capable of
interbreeding until they had asserted their right to such classification
by breeding with tolerable certainty. If, again, an animal looked as if
it felt, that is to say, if it moved about pretty quickly or made a
noise, it must be held to feel; if it did neither of these things it did
not look as if it felt, and therefore it must be said not to feel. _De
non apparentibus et non existentibus eadem est lex_ was one of the chief
axioms of their philosophy; no writers have had a greater horror of
mystery or of ideas that have not become so mastered as to be, or to have
been, superficial. Lamarck was one of those men of whom I believe it has
been said that they have brain upon the brain. He had his theory that an
animal could not feel unless it had a nervous system, and at least a
spinal marrow--and that it could not think at all without a brain--all
his facts, therefore, have to be made to square with this. With Buffon
and Dr. Darwin we feel safe that however wrong they may sometimes be,
their conclusions have always been arrived at on that fairly superficial
view of things in which, as I have elsewhere said, our nature alone
permits us to be comforted.

To these writers, then, the doctrine of final causes for rudimentary
organs was a piece of mystification and an absurdity; no less fatal to
any such doctrine were the processes of embryological development. It
was plain that the commonly received teleology must be given up; but the
idea of design or purpose was so associated in their minds with
theological design that they avoided it altogether. They seem