Harvey Mackay, U.S. Entrepreneur and author in Speechwriter's Newsletter, quoted in Bits & Pieces, July 20, 1995, pp. 20-22.
Do you remember the four-minute mile? They'd been trying to do it since the days of the ancient Greeks. Someone found the old records of how the Greeks tried to accomplish this. They had wild animals chase the runners, hoping that would make them run faster. They tried tiger's milk: not the stuff you get down at the supermarket, I'm talking about the real thing.
Nothing worked, so they decided it was physically impossible for a human being to run a mile in four minutes. Our bone structure was all wrong, the wind resistance was too great, our lung power was inadequate. There were a million reasons.
Then one day one human being proved that the doctors, the trainers, and the athletes themselves were all wrong. And, miracle of miracles, the year after Roger Bannister broke the four-minute mile. And the year after that three hundred runners broke the four-minute mile!