Tusculan Disputations 1 ¶90 — Cicero (on the Stoics)

Cicero (on the Stoics), Tusculan Disputations 1 ¶90

We may add that the soul can the more easily escape from this air, which I have often named, and break through it, because nothing is swifter than the soul. No swiftness is comparable to the swiftness of the soul, which, should it remain uncorrupt and without alteration, must necessarily be carried on with such velocity as to penetrate and divide all this atmosphere where clouds, and rain, and winds are formed, which, in consequence of the exhalations from the earth, is moist and dark: but, when the soul has once got above this region, and falls in with and recognizes a nature like its own, it then rests upon fires composed of a combination of thin air and a moderate solar heat, and does not aim at any higher flight. For then, after it has attained a lightness and heat resembling its own, it moves no more, but remains steady, being balanced, as it were, between two equal weights. That, then, is its natural seat where it has penetrated to something like itself, and where, wanting nothing further, it may be supported and maintained by the same aliment which nourishes and maintains the stars.