Has there ever been an athlete more beautiful than Muhammad Ali?  The quick, bouncing footwork, the smooth twist of his waist, the whip of his jabs: With a body by Michelangelo, the world's greatest boxer was a paragon of grace.

Ali put his opponents in pain. He gleefully goaded Joe Frazier to fuel one of the greatest rivalries in all of sports. In his prime fighting years, he was the opposite of humble. And he was, after all, a heavyweight. Grace wasn't supposed to be one of his qualities, which only made Ali's finesse in the ring more surprising, and more delightful.

No heavyweight had ever been so agile. His athleticism came through as a dance, smooth and swift and light. He was a heavyweight who fought like a lightweight, dancing around the ring, making his rivals chase him, frustrating them by adjusting his angle of attack. But Ali wasn't just mobile, he seemed to be effortlessly skimming the ring as if he were skimming the surface of the moon. He played with rhythms as a dancer does, quickening and slowing his footwork, adding the element of surprise. And he knew that what he was doing was art.

Here's a glamorous Ali demonstrating one of the moves he made famous in the ring: the Ali Shuffle. He shows us all the facets, like a jeweler holding a diamond to the light.

In 1969, when Madison Square Garden was closed to Ali, he took his moves to Broadway. This was during the period when Ali was banned from his sport because he refused to respond to his Vietnam War draft notice. He starred in a musical called "Buck White," playing a militant black lecturer, and was praised by Clive Barnes, the New York Times theater and dance critic, for his "pleasant voice" and the "innate dignity" of his moves.

Ali was made for the stage. He had the physical proportions of a dancer: long legs, slim waist and muscles built to do an efficient job, but not to overdo it. Compare his relatively modest musculature with that of, say, Evander Holyfield, whose neck and shoulders rise in mounds. Ali has the smooth, rolling contours of the Appalachians; Holyfield, the sharp peaks of the Rockies.

It's tempting to look to nature as well as to such great artists as Michelangelo to find corollaries to Ali's physical form. His physique was sculpted according to the timeless design principles of balance, order and harmony. He seemed always to be in equilibrium, yet he was never stiff, moving easily from the waist, bending and giving, rather than stepping from his knees, as some heavyweights do.

Like a great showman, Ali took pleasure in his abilities. Watching him, even now, we feel pumped up, too — that's one of his enduring gifts. He spread the joy around. Instead of setting himself apart with off-putting arrogance and cold condescension, Ali swept us up in his delight. He was human, and as prone to outrage as anyone who fights for a living. But more often than not, even in his defiance he was also warm and funny, making googly eyes to the camera, rhyming his boasts with the merry dramatics of a storyteller in the children's section of the library. 

Naturally, the beauty of Ali appeals to a dance critic's eye. But at the outset of Ali's career, his physical grace was not always appreciated by fans of the sport.

"There were so many skeptics early on," says Larry Merchant, the longtime boxing analyst, formerly of HBO, who spent much of his career being surprised and fascinated by Ali. He also happens to be my uncle. "Nobody had ever seen a big man, an athlete, a heavyweight, move like that. People thought, 'Well, maybe he was more a showman than a champion.' No one in the early days understood, though, the fierce will to win that he had, and the ability to slow down and take punches."

The way he carried himself was provocative in its elegance.

"He mocked the whole idea of the rough, tough fighter by talking about how pretty he was," says my uncle. "He knew that would arouse people and agitate his opponents."

Ali inhabited his body with ease, but he also moved through his life outside the ring with breathtaking grace. He knew well the power of his worldwide celebrity, and he used it to combat the evil of racism, speaking out for tolerance and respect. Even when weakened by Parkinson's disease, he pursued humanitarian causes. In 1990, Ali flew to Iraq to meet with Saddam Hussein about the release of American hostages.

He flew home with all 15 of them.