The memories remain: At his peak, up on his toes, circling, flicking jabs so fast you'd lose count, he was a sight to behold.
It was true, what they said, that he really could dance between the raindrops.
But what is left now is a brittle shell, a frail husk, wracked by uncontrollable tremors. The legs that once danced across the seven seas no longer work and leave him land-bound and struggling to stand. And the voice that once loosed a thousand poems is imprisoned in a slurring, rasping whisper. He has become a virtual mime.
He was a Pied Piper, who needed to do nothing more than sit on a park bench and instantly be surrounded. They claimed there was a time when he was better known than the pope. In fact, the pope once asked for his autograph.
In a rollicking, tumultuous lifetime he has undergone an extraordinary transformation. He is now applauded by those who used to revile him, and in the process has become a symbol of what the poet urged: Do not go gentle into that good night, rather rage, rage against the dying of the light.
Each time you see him, you feel a stab of pity but also a lightning bolt of admiration. For he resists . . . he resists.
And he does so without complaint, despite all the infirmities and the indignities that age and illness bring on. He still, laboring, works to muster a smile and a wave, and the crowds still chant, as if on cue: Ali, Ali, Ali . . .
He is in the midst now of six birthday celebrations, each tied to his charities, each RSVP and each with perfect attendance, and no surprise there, for who would dare turn down Ali, Ali, Ali?
"Old age," he said once, "makes you ugly, that's all."
No, no it doesn't. Not if you do it right.
Not if you understand the bargain, and make your peace with the trade-off, which is, as has been noted, great men have to die twice. First when they're great, and then as a man.
Old age is, indeed, a hard road to glory for those who have had sizable rations of both luck and privilege. It is as if a bill has come due for all the enjoyment permitted in that first life.
The higher the pedestal, the farther the fall.
Which brings us to the lion in winter, Joseph Vincent Paterno, another icon toppled.
He and Ali are tethered by a common bond.
The deposed Penn State coach became something of a traffic hazard these last few years, what with taking bone-breaking hits on the sidelines. Combative and defiant as always, he would bounce back up and dutifully impress his charges, who were young enough to be his grandsons. (Did you see what JoePa did this week? Three broken ribs and he never missed a practice.)
But there came the inevitable day when he was slow to get up, and finally unable to get up at all. Snarling his defiance, he finally surrendered and agreed to retreat to the press box roost where he took out his frustrations on the first set of ears he could find. He spent a lifetime on the sideline, so this capitulation really gnawed at his innards.
Then came the midnight blindside and ambush, the cowardly firing by the trustees. Wounded, he sought sanctuary at the place he knows best - home, and there he was, minus only the ankle bracelets, a virtual prisoner.
And then, in that place where he knows best, where he could walk blindfolded, he fell, and as is often the case when the elderly fall, a bone broke. His pelvis snapped like a twig.
And finally, to complete the nightmare: cancer.
It feels like piling on, doesn't it?
He turned 85 last month. Eighty-five. And still he resists, still refusing to surrender. On Saturday, his family was summoned to the hospital where he is reported to be in serious condition.
Others are being marshaled now to fight the fight for him.
Disgruntled alumni, convinced that there was a hidden rush to judgment - which seems more and more plausible the more you think on it - and that the Sandusky scandal was just a convenient way to get rid, once and for good, of the man who apparently intended to coach forever.
We were seated at a banquet some years ago and Paterno told me how, when Roman conquerors marched into a newly captured city, there were slaves behind them, cautioning: "You're not as great as you think; you're not as great . . ."
And he said: "They're right, you know."