From Writer's Almanac:
It's the birthday of Muhammad Ali, born Cassius Clay in Louisville, Kentucky (1942). He started boxing when he was 12 years old, after his bicycle got stolen. He went to report the theft to the nearest police officer, who was coaching boxing practice at the time and invited Cassius to work out with his boxing program.
His motto was "Float like a butterfly, sting like a bee." He won the world heavyweight boxing championship title in 1964, the same year that he converted to the Nation of Islam and changed his name to Muhammad Ali.
One of his coaches, Angelo Dundee, said, "Of all the fighters I've ever known, only he could make the heavy bag sing when he hit it. He ran 11 miles to the gym from the hotel and back every day along the causeway. He was always the first in and the last out of the gym. He is the most unspoiled kid I've ever had."