AFICIONADOS call boxing the “sweet science,” but it is neither sweet nor scientific. What it is is an unforgiving sport, and often a brutal one; last Saturday we got another shocking reminder of the sometimes casual cruelty of boxing. Up-and-coming Filipino boxer Z Gorres wound up in a medically induced coma done to relieve a swelling in his brain; he had collapsed immediately after winning a steppingstone bout in Las Vegas. His situation, as of press time, remains critical.

The day after Gorres’ nightmare began, Manny Pacquiao reminded us with his fearless, masterly victory over welterweight champion Miguel Cotto why he is now the undisputed best boxer in the world, at any weight: He makes boxing look easy. He does not only satisfy his countryman’s appetite for ungrudging respect; he does not only answer the need of the sports fan for graceful, explosive athleticism, for sheer physical excellence; he also pleases the spectator’s naive fantasy that the violence in the ring, like violence seen on screen, carries no serious consequences.

It does, of course. All we have to do is remember Gorres’ fate; or contemplate the damage Parkinson’s has visited on the most celebrated boxer of all time, Muhammad Ali; or listen to Freddie Roach, the coach who charted Pacquiao’s rise to global superstardom, when he advised his ward, whom he has taken to calling “son,” to fight only one or two more times, and then quit. He has nothing more to prove, the cerebral Roach has said. (That Roach himself has Parkinson’s, like Ali’s the curse of a career spent fighting and absorbing punishment in the ring, adds more weight to his advice.)

The Filipino fan basking in the lasting sunlight of Pacquiao’s impressive, history-setting victory will find it hard to listen to, much less hear, Roach’s advice. Why even entertain dark notions about quitting? Didn’t Pacquiao celebrate his 12th-round TKO win by proceeding to his pre-scheduled “mini-concert” mere hours after the fight? Didn’t 12 rounds of fighting with the biggest boxer he had ever faced leave Pacquiao looking none the worse for wear? Didn’t he end many a round actually smiling on his way back to his corner?

But Roach is right; Pacquiao has nothing more to prove. Yes, there is a multimillion-dollar bout waiting for him, against former pound-for-pound king Floyd Mayweather Jr. But if the fight everyone wants to see does not push through, it will be Mayweather’s loss. Pacquiao has beaten all the other Hall of Fame-bound rivals of his era; he has graduated beyond the pound-for-pound rankings. He is, as Roach has said, already on the list of boxing’s all-time greats.

He has nothing more to prove. Perhaps a couple of more fights, to tie up loose ends, to cement his fearsome reputation, to push boxing back into the mainstream. In the Time cover story, Pacquiao kept asserting a mantra of sorts. “Di ako bobo,” he said again and again: I am not stupid.

He has certainly proven that, both inside the ring, with his tenacious training discipline and sense of ring strategy, and outside it, in choosing the right opponents at the right time, in taking care to grow and protect his hard-earned fortune. But the curse of boxing afflicts even the greatest of boxers: Not knowing when to hang up one’s gloves. As a result, from Ali on down, we have seen great fighters fight way past their prime—to recapture past glory, or to recover lost fortune, or to lay old ghosts or demons to rest.

Quitting at the peak of his career: This, then, would be the acid test of Pacquiao’s obvious intelligence.

In the meantime, we can enjoy the highlights of a storybook fighting career—the exciting trilogy with Morales, the complete domination of Barrera, the difficult but ultimately triumphant pair of fights with Marquez, the two-round demolition of Hatton, the victory over true welterweight Cotto and, above all, the destruction of the previous global boxing superstar, De La Hoya, in a true Dream Match. We can also, and perhaps especially, follow the trajectory of his development as a compleat boxer over and over. To watch a talented fighter grow better with each match, to witness a man achieve greatness by bending both nature and history to his will, is the fan’s, the Filipino’s, true privilege.