Gregory of Nazianzus, on Prov 26:12

“Hast thou seen a man wise in his own conceit? there shall be more hope of a fool than of him.”

“There is an evil which I have seen under the sun, a person wise in his own conceit; and a still greater evil is to charge with the instruction of others a person who is not even aware of his own ignorance.”

Imported from an open dataset — not yet checked against the printed edition.