everywhere today. But how rare is the true
idea! Let us ask the astronomers who originate cosmogonical hypotheses,
and invent a primitive nebula, the natural philosophers who dream that
by the deterioration of energy and the dissipation of movement the
material world will obtain final rest in the inertia of a homogeneous
equilibrium, let us ask the biologists and psychologists who are enemies
of fixed species and inquisitive about ancestral history. What they
are anxious to discern in evolution is the persistent influence of an
initial cause once given, the attraction of a fixed end, a collection
of laws before the eternity of which change becomes negligible like
an appearance. Now he who thinks of the universe as a construction of
unchangeable relations denies by his method the evolution of which he
speaks, since he transforms it into a calculable effect necessarily
produced by a regulated play of generating conditions, since he
implicitly admits the illusive character of a becoming which adds
nothing to what is given.

Finality itself, if he keeps the name, does not save him from his error,
for finality in his eyes is nothing but an efficient cause projected
into the future. So we see him fixing stages, marking periods, inserting
means, putting in milestones, continually destroying movement by halting
it before his gaze. And we all do the same by instinctive inclination.
Our concept of law, in its classical form, is not general: it represents
only the law of co-existence and of mechanism, the static relation
between two numerically disconnected terms; and in order to grasp
evolution we shall doubtless have to invent a new type of law: law in
duration, dynamic relation. For we can, and we must, conceive that there
is an evolution of natural laws; that these laws never define anything
but a momentary state of things; that they are in reality like streaks
determined in the flux of becoming by the meeting of contrary currents.
"Laws," says Monsieur Boutroux, "are the bed down which passes the
torrent of facts; they have dug it, though they follow it." Yet we
see the common theories of evolution appealing to the concepts of the
present to describe the past, forcing them back to prehistoric times,
and beyond the reasoning of today, placing at the beginning what is
only conceivable in the mind of the contemporary thinker; in a word,
imagining the same laws as always existing and always observed. This
is the method which Mr