The following story is attributed to Kermit L. Long:
Two men were walking along a crowded sidewalk in a downtown business area. Suddenly one exclaimed: “Listen to the lovely sound of that cricket.” But the other could not hear. He asked his companion how he could detect the sound of a cricket amid the din of people and traffic.
The first man, who was a zoologist, had trained himself to listen to the voices of nature. But he didn’t explain. He simply took a coin out of his pocket and dropped it to the sidewalk, whereupon a dozen people began to look about them.
“We hear,” he said, “what we listen for.”