WHAT IS THE ESSENCE OF THE STARS, AND HOW THEY ARE COMPOSED.
Thales believes that they are globes of earth set on fire. Empedocles,
that they are fiery bodies arising from that fire which the ether
embraced within itself, and did shatter in pieces when the elements
were first separated one from another. Anaxagoras, that the
circumambient ether is of a fiery substance, which, by a vehement
force in its whirling about, did tear stones from the earth, and by
its own power set them on fire, and establish them as stars in the
heavens. Diogenes thinks they resemble pumice stones, and that they are
the breathings of the world; again he supposeth that there are some
invisible stones, which sometimes fall from heaven upon the earth, and
are there quenched; as it happened at Aegos-potami, where a stony star
resembling fire did fall. Empedocles, that the fixed stars are fastened
to the crystal, but the planets are loosened. Plato, that the stars
for the most part are of a fiery nature, but they are made partakers
of another element, with which they are mixed after the resemblance of
glue. Xenophanes, that they are composed of inflamed clouds, which
in the daytime are quenched, and in the night are kindled again. The
like we see in coals; for the rising and setting of the stars is
nothing else but the quenching and kindling of them. Heraclides and
the Pythagoreans, that every star is a world in an infinite ether, and
itself encompasseth air, earth, and ether; this opinion is current
among the followers of Orpheus, for they suppose that each of the stars
does make a world. Epicurus condemns none of these opinions, for he
embraces any thing that is possible.