under certain circumstances of the characteristics of the opposite
sex, the latency of memory, the unconsciousness with which we grow,
and indeed perform all familiar actions, these points, though
hitherto, most of them, so apparently inexplicable that no one even
attempted to explain them, became at once intelligible, if the
contentions of "Life and Habit" were admitted.

Before I had finished writing this book I fell in with Professor
Mivart's "Genesis of Species," and for the first time understood the
distinction between the Lamarckian and Charles-Darwinian systems of
evolution. This had not, so far as I then knew, been as yet made
clear to us by any of our more prominent writers upon the subject of
descent with modification; the distinction was unknown to the
general public, and indeed is only now beginning to be widely
understood. While reading Mr. Mivart's book, however, I became
aware that I was being faced by two facts, each incontrovertible,
but each, if its leading exponents were to be trusted, incompatible
with the other.

On the one hand there was descent; we could not read Mr. Darwin's
books and doubt that all, both animals and plants, were descended
from a common source. On the other, there was design; we could not
read Paley and refuse to admit that design, intelligence, adaptation
of means to ends, must have had a large share in the development of
the life we saw around us; it seemed indisputable that the minds and
bodies of all living beings must have come to be what they are
through a wise ordering and administering of their estates. We
could not, therefore, dispense either with descent or with design,
and yet it seemed impossible to keep both, for those who offered us
descent stuck to it that we could have no design, and those, again,