True story. When I was at college, there was an old black man named Francis that lived in a cabin behind the college. He wasn't quite "right" in his intellects, and would walk through the college mumbling and talking to himself, with the occasional loud argument (with himself).
He made a little money cutting firewood for local folks, so he would stalk down the road with an axe over his shoulder; for 50 years, he was known as Francis the Axeman. Wouldn't hurt a soul, but looked a bit scary to those who didn't know him.
College boys being what they are, they'd play off their humor on him sometimes. It was popular to offer Francis his choice of a nickel or a dime; the nickel being larger, Francis would always choose the nickel and go on his way.
One day, one of the faculty said "Francis, don't you know that a dime is worth as much as two nickels? Why don't you choose the dime?"
And Francis said (he stuttered bad, but you could understand him) "Well suh, did I start choosin' the dime, they'd quit doin' it, wouldn't they .... "