John was a patient living in a mental hospital since many years. Lately, he had developed this habit of putting his ear to the wall and listening.
The hospital doctor would watch John do this day after day. One day, the doctor finally decided to see what John was listening to, so he put his ear up to the wall and listened. He heard nothing.
So he turned to John and said, “I don’t hear anything.”
John said, “Yeah, I know. It’s been like that for many months now!”