Leucippus holds that the whole is infinite. . . part of it is full and part
void. . . Hence arise innumerable worlds, and are resolved again into these
elements. The worlds come into being as follows: many bodies of all sorts of
shapes move `by abscission from the infinite' into a great void; they come
together there and produce a single whirl, in which, colliding with one another
and revolving in all manner of ways, they begin to separate apart, like to
like. But when their multitude prevents them from rotating any longer in
equilibrium, those that are fine go out towards the surrounding void as if
sifted while the rest `abide together' and, becoming entangled, unite their
motions and make a first spherical structure. This structure stands apart like
a `membrane' which contains in itself all kinds of bodies; and as they whirl
around owing to the resistance of the, middle, the surrounding membrane becomes
thin, while contiguousatoms keep flowing togehter owing to contact wiht the
whirl. So the earth came into being, the atoms that had been borne to the
middle abiding together there. Again the containg membrane is itself
increased, owing to the attraction of bodies outside; as it moves around in the
whirl it takes in anything it touches. Some of these bodies that get entangled
form a structure that is at first moist and muddy, but as they revolve with
the whirl of the whole they dry out and then ignite to form the substance of
the heavenly bodies.