When Thales was asked what was difficult, he said, To know one's self. And what was easy, To advise another.

Pythagoras used to say that he had received as a gift from Mercury the perpetual transmigration of his soul, so that it was constantly transmigrating and passing into all sorts of plants or animals.

If appearances are deceitful, then they do not deserve any confidence when they assert what appears to them to be true.

Anaximander used to assert that the primary cause of all things was the Infinite,-not defining exactly whether he meant air or water or anything else.

One of the sayings of Diogenes was that most men were within a finger's breadth of being mad; for if a man walked with his middle finger pointing out, folks would think him mad, but not so if it were his forefinger.

But Chrysippus, Posidonius, Zeno, and Boëthus say, that all things are produced by fate. And fate is a connected cause of existing things, or the reason according to which the world is regulated.

Whichever you do, you will repent it.