on as distinct from all
other modes of motion, such as heat, light, electricity, as these are
distinct from each other.

When we speak of force of mind, force of character, we of course speak
in parables, since the force here alluded to is an experience of our own
minds entirely and would not suffice to move the finest dust-particle in
the air.

There could be no vegetable or animal life without the sunbeam, yet when
we have explained or accounted for the growth of a tree in terms of the
chemistry and physics of the sunbeam, do we not have to figure to
ourselves something in the tree that avails itself of this chemistry,
that uses it and profits by it? After this mysterious something has
ceased to operate, or play its part, the chemistry of the sunbeam is no
longer effective, and the tree is dead.

Without the vibrations that we call light, there would have been no eye.
But, as Bergson happily says, it is not light passively received that
makes the eye; it is light meeting an indwelling need in the organism,
which amounts to an active creative principle, that begets the eye. With
fish in underground waters this need does not arise; hence they have no
sight. Fins and wings and legs are developed to meet some end of the
organism, but if the organism were not charged with an expansive or
developing force or impulse, would those needs arise?

Why should the vertebrate series have risen through the fish, the
reptile, the mammal, to man, unless the manward impulse was inherent in
the first vertebrate; something that struggled, that pushed on and up
from the more simple to the more complex forms? Why did not unicellular
life always remain unicellular? Could not the environment have acted
upon it endlessly without causing it to change toward higher and more
complex forms, had there not been some indwelling aboriginal tendency
toward these forms? How could natural selection, or any other process of
selection, work upon species to modify them, if there were not something
in species pushing out and on, seeking new ways, new forms, in fact some
active principle that is modifiable?

Life has risen by stepping-stones of its dead self to higher things. Why
has it risen? Why did it not keep on the same level, and go through the
cycle of change, as the inorganic does, without attaining to higher
forms? Because, it may be replied, it was life, and not mere matter and
motion--something that lifts matter and motion to a new plane.