or abstract theories on physics, except as an adjunct and support to
his moral conceptions, Epicurus seems to have had very little
inclination. He thus speaks of the visible universe or Cosmos. [373]
The Cosmos is a sort of skyey enclosure, which holds within it the
stars, the earth, and all visible things. It is cut off from the
infinite by a wall of division which may be either rare or dense, in
motion or at rest, round or three-cornered or any other form. That
there is such a wall of division is quite admissible, for no object of
which we have observation is without its limit. Were this wall of
division to {220} break, everything contained within it would tumble
out. We may conceive that there are an infinite number of such Cosmic
systems, with inter-cosmic intervals throughout the infinity of space.

He is very disinclined to assume that similar phenomena, _e.g._
eclipses of the sun or moon, always have the same cause. The various
accidental implications and interminglings of the atoms may produce the
same effect in various ways. In fact Epicurus has the same impatience
of theoretical physics as of theoretical philosophy. He is a
'practical man.'

[378]

He is getting nearer his object when he comes to the nature of the
soul. The soul, like everything else, is composed of atoms, extremely
delicate and fine. It very much resembles the breath, with a mixture
of heat thrown in, sometimes coming nearer in nature to the first,
sometimes to the second. Owing to the delicacy of its composition it
is extremely subject to variation, as we see in its passions and
liability to emotion, its phases of thought and the varied experiences
without which we cannot live. It is, moreover, the chief cause of
sensation being possible for us. Not that it could of itself have had
sensation, without the enwrapping support of the rest of the structure.
The rest of the structure, in fact, having prepared this chief cause,
gets from it a share of what comes to it, but not a share of all which
the soul has.

The soul being of material composition equally {221} with the other
portions of the bodily structure, dies of course with it, that is, its
particles like the rest are dispersed, to form new bodies. There is
nothing dreadful therefore about death, for there is nothing left to
know or feel anything about it.

As regards the process of sensation, Epicurus, like Democritus,
conceived bodies as having a power of emitting fro