It's a wise man who profits by his own experience, but it's a good deal wiser one who lets the rattlesnake bite the other fellow.
Wisdom has never made a bigot, but learning has.
Theory looks well on paper, but does not amount to anything without practice.
Advice maybe wrong, but examples prove themselves.
It AIN'T so much the things we don't know that get us into trouble. It's the things we know that just ain't so.
Pity cost nothing and ain't worth nothing.