269
Str. Absolute and perpetual immutability is a property of only the most divine things of all, and body does not belong to this class. Now that which we call heaven and the universe has received from its creator many blessed qualities, but then, too, it partakes also of a bodily nature; therefore it is impossible for it to be entirely free from change; it moves, however, so far as it is able to do so, with a single motion in the same place and the same manner, and therefore it has acquired the reverse motion in a circle, because that involves the least deviation from its own motion. But to turn itself for ever is hardly possible except for the power that guides all moving things; and that this should turn now in one direction and now in the opposite direction is contrary to divine law.
270
Str. As the result of all this, we must not say either that the universe turns itself always, or that it is always turned by God in two opposite courses, or again that two divinities opposed to one another turn it. The only remaining alternative is what I suggested a little while ago, that the universe is guided at one time by an extrinsic divine cause, acquiring the power of living again and receiving renewed immortality from the Creator, and at another time it is left to itself and then moves by its own motion, being left to itself at such a moment that it moves backwards through countless ages, because it is immensely large and most evenly balanced, and turns upon the smallest pivot.
270
Y. Soc. All that account of yours appears, at any rate, very reasonable.
270
Str. Then, in the light of what has been said, let us consider and gain understanding of the event which we said was the cause of all those wonderful portents; for it is really just this.
270
Y. Soc. Just what?
270
Str. The fact that at certain periods the universe has its present circular motion, and at other periods it revolves in the reverse direction.
270
Y. Soc. How was this the cause?
