UTION OF LIFE. TORPOR, INTELLIGENCE,
INSTINCT

The evolution movement would be a simple one, and we should soon have
been able to determine its direction, if life had described a single
course, like that of a solid ball shot from a cannon. But it proceeds
rather like a shell, which suddenly bursts into fragments, which
fragments, being themselves shells, burst in their turn into fragments
destined to burst again, and so on for a time incommensurably long. We
perceive only what is nearest to us, namely, the scattered movements of
the pulverized explosions. From them we have to go back, stage by stage,
to the original movement.

When a shell bursts, the particular way it breaks is explained both by
the explosive force of the powder it contains and by the resistance of
the metal. So of the way life breaks into individuals and species. It
depends, we think, on two series of causes: the resistance life meets
from inert matter, and the explosive force--due to an unstable balance
of tendencies--which life bears within itself.

The resistance of inert matter was the obstacle that had first to be
overcome. Life seems to have succeeded in this by dint of humility, by
making itself very small and very insinuating, bending to physical and
chemical forces, consenting even to go a part of the way with them, like
the switch that adopts for a while the direction of the rail it is
endeavoring to leave. Of phenomena in the simplest forms of life, it is
hard to say whether they are still physical and chemical or whether they
are already vital. Life had to enter thus into the habits of inert
matter, in order to draw it little by little, magnetized, as it were, to
another track. The animate forms that first appeared were therefore of
extreme simplicity. They were probably tiny masses of scarcely
differentiated protoplasm, outwardly resembling the amoeba observable
to-day, but possessed of the tremendous internal push that was to raise
them even to the highest forms of life. That in virtue of this push the
first organisms sought to grow as much as possible, seems likely. But
organized matter has a limit of expansion that is very quickly reached;
beyond a certain point it divides instead of growing. Ages of effort and
prodigies of subtlety were probably necessary for life to get past this
new obstacle. It succeeded in inducing an increasing number of elements,
ready to divide, to remain united. By the division of labor it knotted
between