. . . if you can tell the difference between good advice and bad advice, you don't need advice.
Two can live as cheaply as one - if they both have good jobs.
If two wrongs don't make a right, try three.
A censor is an expert in cutting remarks. A censor is a man who knows more than he thinks you ought to.
As a matter of fact is an expression that precedes many an expression that isn't.
Incompetence plus incompetence equals incompetence.