o the employment of its first
means--namely, of a force entirely external and foreign to the
animal--its work would have remained very important; the animals
would have remained machines totally passive, and she would never
have given origin in any of these living beings to the admirable
phenomena of sensibility, of inmost feelings of existence which
result therefrom, of the power of action, finally, of ideas, by
which she can create the most wonderful of all, that of thought--in
a word, intelligence.

"But, wishing to attain these grand results, she has by slow degrees
prepared the means, in gradually giving consistence to the internal
parts of animals; in differentiating the organs, and in multiplying
and farther forming the fluids contained, etc., after which she has
transported into the interior of these animals that force productive
of movements and of actions which in truth it would not dominate at
first, but which she has come to place, in great part, at their
disposition when their organization should become very much more
perfect.

"Indeed, from the time that the animal organization had sufficiently
advanced in its structure to possess a nervous system--even slightly
developed, as in insects--the animals provided with this
organization were endowed with an intimate sense of their existence,
and from that time the force productive of movements was conveyed
into the very interior of the animal.

"I have already made it evident that this internal force which
produces movements and actions should derive its origin in the
intimate feeling of existence which animals with a nervous system
possess, and that this feeling, solicited or aroused by needs,
should then start into motion the subtile fluid contained in the
nerves and carry it to the muscles which should act, this producing
the actions which the needs require.

"Moreover, every want felt produces an emotion in the inner feeling
of the individual which experiences it; and from this emotion of the
feeling in question arises the force which gives origin to the
movement of the parts which are placed in activity....

"Thus, in the animals which possess the power of acting--namely, the
force productive of movements and actions--the inner feeling, which
on each occasion originates this force, being excited by some need,
places in action the power or force in question; excites the
move