The Hearing Test

The old perfesser, unfortunately, once spent some time in a mental hospital. All day long he had his ear to the wall, listening. The doctor would watch the old perfesser do this day after day.

The doctor finally decided to see what he was listening to, so he put his ear up to the wall and listened. He heard nothing.

He turned to his patient and said, "I don't hear anything."

The old perfesser said, "Yeah, I know. It's been like that for months!"