nothing; without mental concepts, where
are we? Natural selection is as much a metaphysical phrase as is
consciousness, or the subjective and the objective. Natural selection is
not an entity, it is a name for what we conceive of as a process. It is
natural rejection as well. The vital principle is a metaphysical
concept; so is instinct; so is reason; so is the soul; so is God.

Many of our concepts have been wrong. The concept of witches, of disease
as the work of evil spirits, of famine and pestilence as the visitation
of the wrath of God, and the like, were unfounded. Science sets us right
about all such matters. It corrects our philosophy, but it cannot
dispense with the philosophical attitude of mind. The philosophical must
supplement the experimental.

In fact, in considering this question of life, it is about as difficult
for the unscientific mind to get along without postulating a vital
principle or force--which, Huxley says, is analogous to the idea of a
principle of aquosity in water--as it is to walk upon the air, or to
hang one's coat upon a sunbeam. It seems as if something must breathe
upon the dead matter, as at the first, to make it live. Yet if there is
a distinct vital force it must be correlated with physical force, it
must be related causally to the rest. The idea of a vital force as
something new and distinct and injected into matter from without at a
given time and place in the earth's history, must undoubtedly be given
up. Instead of escaping from mechanism, this notion surrenders one into
the hands of mechanism, since to supplement or reinforce a principle
with some other principle from without, is strictly a mechanical
procedure. But the conception of vitality as potential in matter, or of
the whole universe as permeated with spirit, which to me is the same
thing, is a conception that takes life out of the categories of the
fortuitous and the automatic.

No doubt but that all things in the material world are causally related,
no doubt of the constancy of matter and force, no doubt but that all
phenomena are the result of natural principles, no doubt that the living
arose from the non-living, no doubt that the evolution process was
inherent in the constitution of the world; and yet there is a mystery
about it all that is insoluble. The miracle of vitality takes place
behind a veil that we cannot penetrate, in the inmost sanctuary of the
molecules of matter, in that invisible, imaginary world on