Arcesilaus had a peculiar habit while conversing of using the expression, "My opinion is," and "So and so will not agree to this.

There is a written and an unwritten law. The one by which we regulate our constitutions in our cities is the written law; that which arises from customs is the unwritten law.

Whichever you do, you will repent it.

Apollodorus says, "If any one were to take away from the books of Chrysippus all the passages which he quotes from other authors, his paper would be left empty.

Diogenes, when asked from what country he came, replied, "I am a citizen of the world."

Bury me on my face," said Diogenes; and when he was asked why, he replied, "Because in a little while everything will be turned upside down.

When asked what learning was the most necessary, he said, “Not to unlearn what you have learned!”