But while he judges of what is best by his palate, he does not look up to the "palace of heaven," as Ennius calls it.
XIX.

For as there are two sorts of stars,[129] one kind of which measure their journey from east to west by immutable stages, never in the least varying from their usual course, while the other completes a double revolution with an equally constant regularity; from each of these facts we demonstrate the volubility of the world (which could not possibly take place in any but a globular form) and the circular orbits of the stars.

And first of all the sun, which has the chief rank among all the stars, is moved in such a manner that it fills the whole earth with its light, and illuminates alternately one part of the earth, while it leaves the other in darkness.

The shadow of the earth interposing causes night; and the intervals of night are equal to those of day.

And it is the regular approaches and retreats of the sun from which arise the regulated degrees of cold and heat.