and shades; it is measured by our capacity for the inner life. Liberty is
a thing which goes on in us unceasingly: our liberty is potential rather
than actual. And lastly, it is a thing of duration, not of space and
number, not the work of moments or decrees. The free act is the act which
has been long in preparing, the act which is heavy with our whole history,
and falls like a ripe fruit from our past life.

But how are we to establish positive verification of these views? How are
we to do away with the danger of illusion? The proof will in this case
result from a criticism of adverse theories, along with direct observation
of psychological reality freed from the deceptive forms which warp the
common perception of it. And it will here be an easy task to resume Mr
Bergson's reasoning in a few words.

The first obstacle which confronts affirmation of our liberty comes from
physical determinism. Positive science, we are told, presents the universe
to us as an immense homogeneous transformation, maintaining an exact
equivalence between departure and arrival. How can we possibly have after
that the genuine creation which we require in the act we call free?

The answer is that the universality of the mechanism is at bottom only a
hypothesis which is still awaiting demonstration. On the one hand it
includes the parallelist conception which we have recognised as effete.
And on the other it is plain that it is not self-sufficient. At least it
requires that somewhere or other there should be a principle of position
giving once for all what will afterwards be maintained. In actual fact,
the course of phenomena displays three tendencies: a tendency to
conservation, beyond question; but also a tendency to collapse, as in the
diminution of energy; and a tendency to progress, as in biological
evolution. To make conservation the sole law of matter implies an