Von Neumann and Nobert Weiner were both the subject of many dotty
professor stories. Von Neumann supposedly had the habit of simply
writing answers to homework assignments on the board (the method
of solution being, of course, obvious) when he was asked how to solve
problems. One time one of his students tried to get more helpful
information by asking if there was another way to solve the problem.
Von Neumann looked blank for a moment, thought, and then answered,
"Yes.".