f chyle, we shall consider each of the two as a whole, not as
a part.

Let us imagine, with your permission, a little worm, living in the
blood, able to distinguish by sight the particles of blood, lymph, etc.,
and to reflect on the manner in which each particle, on meeting with
another particle, either is repulsed, or communicates a portion of its
own motion. This little worm would live in the blood in the same way as
we live in a part of the universe, and would consider each particle of
blood, not as a part, but as a whole. He would be unable to determine
how all the parts are modified by the general nature of blood, and are
compelled by it to adapt themselves so as to stand in a fixed relation
to one another. For if we imagine that there are no causes external to
the blood, which could communicate fresh movements to it, nor any space
beyond the blood, nor any bodies whereto the particles of blood could
communicate their motion, it is certain that the blood would always
remain in the same state, and its particles would undergo no
modifications, save those which may be conceived as arising from the
relations of motion existing between the lymph, the chyle, etc. The
blood would then always have to be considered as a whole, not as a part.
But as there exist, as a matter of fact, very many causes which modify,
in a given manner, the nature of blood, and are, in turn, modified
thereby, it follows that other motions and other relations arise in the
blood, springing not from the mutual relations of its parts only, but
from the mutual relations between the blood as a whole and external
causes. Thus the blood comes to be regarded as a part, not as a whole.
So much for the whole and the part.

All natural bodies can and ought to be considered in the same way as we
have here considered the blood, for all bodies are surrounded by others,
and are mutually determined to exist and operate in a fixed and definite
proportion, while the relations between motion and rest in the sum total
of them, that is, in the whole universe, remain unchanged. Hence it
follows that each body, in so far as it exists as modified in a
particular manner, must be considered as a part of the whole universe,
as agreeing with the whole, and associated with the remaining parts. As
the nature of the universe is not limited, like the nature of blood, but
is absolutely infinite, its parts are by this nature of infinite power
infinitely modified, and compelled to