Foolishness is indeed the sister of wickedness.
The first step towards madness is to think oneself wise.
Self-will in the man who does not reckon wisely is by itself the weakest of all things.
What makes a fool is an inability to take even his own good advice.
The wrong way always seems the more reasonable.
It is the part of a fool to say, I should not have thought.
I haven't got enough sense not to pitch.
Foolishness is rarely a matter of lack of intelligence or even lack of information.
