Philosophical Works of Lucius Annaeus Seneca, Vol. 1

For those earlier ones were still unaware of the commentaries of Aristotle composed with care on this whole doctrine, whence—to mention it in passing, as I do not know whether it has been observed or sufficiently explained by anyone—it seems to have come about that while all philosophers after him constructing systems, and especially the Stoics and Epicureans, are found to be claiming and amending nothing but older dogmas, the former insisted upon and adhered to the footprints of Heraclitus, the latter to those of Democritus. In which matter it is certain they did not labor poorly. Therefore, it is so far from the case that we should recognize a decline in the waning genius of the Greeks in their studies of cultivating philosophy, or excuse it with Tiedemann, that we must rather praise the diligence and sagacity of the ingenuity of those who left off from Aristotle. Wherefore it seems to have happened that the older authors and professors of the Stoa, having mostly followed Heraclitus, appear to have discovered little themselves in physics, although the acumen of Chrysippus stood out more than the rest, as his opinion on motion, on atoms, etc., is mentioned not without honor. But the more recent Stoa had many excellent authors who treated physics and deserved very well of it, especially Posidonius, whose commentaries Seneca often used and made his own. These and others whom he used employed the books of Aristotle, which had been transferred to Rome not long before, after the capture of Athens by Sulla, and made public a short time later by the diligence and study of Tyrannion of Amisus.

Now, indeed, he converted these and other authors on physical matters—who it is agreed were almost all Greeks—to his own use in such a way that, having exposed their opinions and thoughts, he brings his own judgment to bear, with his own observations mixed in, and either refutes or affirms them, either wholly or in part. And he is accustomed to do this with such experience and modesty that he seems not only to assume the role of a learned man, but in truth to show himself and commend himself as a learned and humane person. This, if in any place of philosophy, in this one certainly, which is about the nature of things, it was fitting for anyone dedicated to this inquiry to observe and exercise the more, the more thorny and uncertain the questions were that were thrown at students of this doctrine—especially in that time, which was destitute of our instruments and aids—which prohibit all boldness and rashness in solving them.