sharp edge, pressed against the future and cutting
into it unceasingly. It is in this that life and action are free. But
suppose we let ourselves go and, instead of acting, dream. At once the
self is scattered; our past, which till then was gathered together into
the indivisible impulsion it communicated to us, is broken up into a
thousand recollections made external to one another. They give up
interpenetrating in the degree that they become fixed. Our personality
thus descends in the direction of space. It coasts around it continually
in sensation. We will not dwell here on a point we have studied
elsewhere. Let us merely recall that extension admits of degrees, that
all sensation is extensive in a certain measure, and that the idea of
unextended sensations, artificially localized in space, is a mere view
of the mind, suggested by an unconscious metaphysic much more than by
psychological observation.

No doubt we make only the first steps in the direction of the extended,
even when we let ourselves go as much as we can. But suppose for a
moment that matter consists in this very movement pushed further, and
that physics is simply psychics inverted. We shall now understand why
the mind feels at its ease, moves about naturally in space, when matter
suggests the more distinct idea of it. This space it already possessed
as an implicit idea in its own eventual _detension_, that is to say, of
its own possible _extension_. The mind finds space in things, but could
have got it without them if it had had imagination strong enough to push
the inversion of its own natural movement to the end. On the other hand,
we are able to explain how matter accentuates still more its
materiality, when viewed by the mind. Matter, at first, aided mind to
run down its own incline; it gave the impulsion. But, the impulsion once
received, mind continues its course. The idea that it forms of _pure_
space is only the _schema_ of the limit at which this movement would
end. Once in possession of the form of space, mind uses it like a net
with meshes that can be made and unmade at will, which, thrown over
matter, divides it as the needs of our action demand. Thus, the space of
our geometry and the spatiality of things are mutually engendered by the
reciprocal action and reaction of two terms which are essentially the
same, but which move each in the direction inverse of the other. Neither
is space so foreign to our nature as we imagine, nor is matter a