ull of the intelligence they dissected;
they seemed to cry to nature: Though thou dost not exist, yet will I
trust in thee. Their idealism was a theoretical scruple rather than a
passionate superstition. Not so M. Bergson; he is not so simple as to
invoke the malicious criticism of knowledge in order to go on thinking
rationalistically. Reason and science make him deeply uncomfortable.
His point accordingly is not merely that mechanism is a hypothesis,
but that it is a wrong hypothesis. Events do not come as if mechanism
brought them about; they come, at least in the organic world, as if a
magic destiny, and inscrutable ungovernable effort, were driving them
on.

Thus M. Bergson introduces metaphysics into natural history; he
invokes, in what is supposed to be science, the agency of a power,
called the _elan vital,_ on a level with the "Will" of Schopenhauer or
the "Unknowable Force" of Herbert Spencer. But there is a scientific
vitalism also, which it is well to distinguish from the metaphysical
sort. The point at issue between vitalism and mechanism in biology is
whether the living processes in nature can be resolved into a
combination of the material. The material processes will always remain
vital, if we take this word in a descriptive and poetic sense; for
they will contain a movement having a certain idiosyncrasy and taking
a certain time, like the fall of an apple. The movement of nature is
never dialectical; the first part of any event does not logically
imply the last part of it. Physics is descriptive, historical,
reporting after the fact what are found to be the habits of matter.
But if these habits are constant and calculable we call the vitality
of them mechanical. Thus the larger processes of nature, no matter how
vital they may be and whatever consciousness may accompany them, will
always be mechanical if they can be calculated and predicted, being a
combination of the more minute and widespread processes which they
contain. The only question therefore is: Do processes such as
nutrition and reproduction arise by a combination of such events as
the fall of apples? Or are they irreducible events, and units of
mechanism by themselves? That is the dilemma as it appears in science.
Both possibilities will always remain open, because however far
mechanical analysis may go, many phenomena, as human apprehension
presents them, will always remain irreducible to any common
denominator with the rest; and on the oth