se from the fact that both suppose ready-made--the former
above the sensible, the latter within the sensible--a science one and
complete, with which any reality that the sensible may contain is
believed to coincide. _For both, reality as well as truth are integrally
given in eternity._ Both are opposed to the idea of a reality that
creates itself gradually, that is, at bottom, to an absolute duration.

* * * * *

Now, it might easily be shown that the conclusions of this metaphysic,
springing from science, have rebounded upon science itself, as it were,
by ricochet. They penetrate the whole of our so-called empiricism.
Physics and chemistry study only inert matter; biology, when it treats
the living being physically and chemically, considers only the inert
side of the living: hence the mechanistic explanations, in spite of
their development, include only a small part of the real. To suppose _a
priori_ that the whole of the real is resolvable into elements of this
kind, or at least that mechanism can give a complete translation of what
happens in the world, is to pronounce for a certain metaphysic--the very
metaphysic of which Spinoza and Leibniz have laid down the principles
and drawn the consequences. Certainly, the psycho-physiologist who
affirms the exact equivalence of the cerebral and the psychical state,
who imagines the possibility, for some superhuman intellect, of reading
in the brain what is going on in consciousness, believes himself very
far from the metaphysicians of the seventeenth century, and very near to
experience. Yet experience pure and simple tells us nothing of the kind.
It shows us the interdependence of the mental and the physical, the
necessity of a certain cerebral substratum for the psychical
state--nothing more. From the fact that two things are mutually
dependent, it does not follow that they are equivalent. Because a
certain screw is necessary to a certain machine, because the machine
works when the screw is there and stops when the screw is taken away, we
do not say that the screw is the equivalent of the machine. For
correspondence to be equivalence, it would be necessary that to any part
of the machine a definite part of the screw should correspond--as in a
literal translation in which each chapter renders a chapter, each
sentence a sentence, each word a word. Now, the relation of the brain to
consciousness seems to be entirely different. Not only does the