Wit without discretion is a sword in the hand of a fool

When a fool has made up his mind the market has gone by

Every man is a fool in some man's opinion

A wise man changes his mind, a fool never

Flattery is never so agreeable as to our blind side; commend a fool for his wit, or a knave for his honesty, and they will receive you into their bosoms

There is small disproportion betwixt a fool who useth not wit because he hath it not and him that useth it not when it should avail him.