For anyone, who has been infatuated with martial arts (and martial art movies of course) for a considerable length of time in their life, that's the question that's been in the air in the past 50 years and it might linger on for another couple of decades still. Was Bruce really the greatest martial artist who ever lived? Was he unbeatable? Or let's leave the quasi-philosophical pretense and get down to Earth: could he beat Muhammad Ali? Or Mike Tyson?
I like the latter formulation of the question. It appeals to a mind who likes to wonder - Ali and Tyson being perhaps the two most iconic pugilists in the popular imagination with a real track record who in their prime had an aura of invincibility - and it's something tangible at the same time. A question that could have been answered. Whereas "was he the greatest martial artist?" - meh. What does that even mean?
Another form of the question would be, pedestrian but valid: would Bruce be a UFC champion today?
I'll give a short answer and a longer one.
Short answer: size
The short answer is that Bruce Lee weighed 145 lbs and Ali did 236. Tyson 220. Any more questions? But let's elaborate.
Not a single boxer or wrestler ever became a world champion in a weight category 80 lbs over his own. Not even close. 20 pounds extra is considered to be an advantage almost impossible to compensate for between professional fighters, no matter who we are talking about.
Perhaps, Bruce was a once-in-a-millenium type of human specimen who could have overcome an obstacle not one of the many thousands of fighters could in the era of television. But until someone points to a boxing/MMA match where a lightweight opponent won against the best of the heavyweight division, I remain proportionally skeptical.
Long answer: not only size but almost everything else, too
Giving the fight to Ali or Tyson simply on the merit of their size would be selling them short. They weren't just lumbering behemoths with sledgehammer hands. Both men were lightning fast (which was an especially scary sight in the case of the tank-like Tyson), incredibly talented, and skilled enough to tower over the rest of the world-class fighters of their respective eras.
And at the risk of committing blasphemy in the eyes of the converted, even without the size difference, I can't imagine that Bruce Lee, who had only 4 years of formal training in an obscure Hong-Kong martial art club (where there probably was no free sparring), and perhaps a lot of streetfight experience, could have matched the technical expertise of either of these men. Tyson at 15 sparred regularly with heavy-weight champions, and Ali was Ali. They were sculpted and pushed to their limits by professional trainers. A natural genius Bruce might have been, but I'd give technical expertise to the boxers.
Furthermore, Lee never demonstrated he had the incredible stamina of a professional boxer or the capacity of them to absorb immense punishment. Occasional spectators might underappreciate the ability to be getting hit over and over again with a force of a human sledgehammer and just carrying on round after round, but it is just as essential for fighters as technical finesse. What for laymen spectators looks like a lackluster round, as boxing matches go, requires stamina way beyond the normal fitness levels of ordinary humans (just try to hit the bag for 3 minutes, and you'll know).
Yeah, but Bruce was a martial artist and Ali and Tyson were just boxers, some might say. Without going too deep into the topic, let's just state the fact that Western boxing was one of the founding blocks of Bruce's personal style. Still, it can be argued that Bruce had kicks, too. And other martial art techniques unfamiliar to boxers, like finger jabs or grappling. True, but I just don't think those would have been enough to compensate for the glaring differences in size, physique, and experience.
I think the reasoning above is unassailable. But it's also unromantic and Lee clearly deserves more. So here comes an even longer version that tries to argue for his case. The outcome will be the same, but I try to give credit to Bruce wherever possible.
Legends and facts
Bruce Lee undisputably was a physically gifted man on the high end of the spectrum. He looked like a skinny bodybuilder. Everyone who knew him is in agreement that he was incredibly strong for his weight. There are photos of him doing push-ups on one finger, and numerous stories about demonstrations where he sent his partners in the air with kicks and punches alike. If only half of that is true, he hit and kicked like a mule. His speed was even more legendary. Even Joe Lewis, one of the greatest American kickboxers of all time, who had a fall-out with Bruce and held the idea of Bruce being able to defeat him laughable, said in an interview, "I never stood in front of another human who was as quick as him".
On the other hand, he still weighed only 145 lbs. If you believe that he really could hit harder than the 220-pound Mike Tyson, probably I won't be able to convince you otherwise (neither would experts on biomechanics). Could Bruce's speed compensate for his disadvantage in strength? Unlikely, and my criterion for changing my mind is similar to the one stated earlier in earlier posts: a real-life example of just half that achievement.
It's harder to pass judgment on his actual fighting skills. Everyone seems to agree that he could
copy any moves from other martial artists (let it be strikes, high kicks, or grappling techniques) and master them in a very short time. A former girlfriend of his, with whom Bruce used to frequent the dance floor where he invented cha-cha-cha steps on the fly, called him a "kinetic genius". But aesthetics don't equal efficiency, and making a move look good on camera is very different from being able to apply it against real opponents. Jackie Chan, Steven Seagal, or Jean-Claude Van Damme looked both lethal and beautiful on the screen. But that's only choreography. None of them had a career in professional fighting, and there is a reason for that.
Regarding Bruce's fighting experience, apart from a single boxing bout in high school (which he won) he never competed. His skills were never pressure-tested against professional sportsmen. I don't believe that there ever was a boxing champion who didn't get better by the hard-won experience in the ring, and won the world title on exactly the same level as he had been before his first official fight. Professional MMA fighters say that doesn't matter how long you have been training, your first fight will suck. The first ten will suck. It's something you get better at, match by match. Not to elaborate any further, there is a world of difference between sparring in training and fighting against someone under immense pressure who wants to knock you out.
On the other hand, Lee regularly trained with the multiple Karate champions of his era, among them Chuck Norris, Joe Lewis, and Mike Stone. These guys were the crème de la crème of their era, and they wouldn't have wasted their time on training with Lee unless they got something out of it. Lee definitely must have been a very good teacher or at least a very good training partner. But that doesn't necessarily mean a lot with regard to him as a fighter. Roger Feder's coach must be one of the best tennis coaches. And he certainly was never nearly as good a tennis player as Federer.
The statements on Bruce's martial art prowess made by various people in interviews or in the media are so contradictory, so full of second or third-hand accounts, that they are all but useless. They either sound like sound clips from hagiographies or at best they only add to the confusion. Many people claimed with confidence that Lee could beat any of his "students" (that covered Norris and Lewis, too) easily. But according to Norris, they never actually sparred (which is also what Lewis said). In an interview, when asked (for the thousandth time, I guess) about who was the better between them, Norris replied smiling, almost blushing. "Look, I was a professional fighter, the middleweight champion of the world. Bruce was an actor". Then he hastily added, "but he was very good!".
Norris gave a completely different answer to a very similar question some decades earlier, in an interview. Replying to "Is Bruce Lee your teacher?", Norris said “We are not good enough to be his students, and he is too good to be our teacher.” But this seems like a lighthearted, self-deprecating jest to evade the question, rather than an honest evaluation. The interview was also part of promoting The Way of the Dragon, thus it was certainly not the place for Norris to demean his colleague.
Another anecdote from Norris relates to the same movie. When Bruce called him in 1970 and offered him the role of the main antagonist (who loses against Bruce's character in one of the most epic martial art duels in movie history), Norris asked jokingly: "So you want to beat the world champion?". To which, in Norris's telling, Bruce replied, "No-no... I want to KILL the world champion!". This joke makes sense only if both Norris and Bruce evaluated each other the same way.
Joe Lewis, who was allegedly the first choice of Bruce to play his opponent in the movie, said he had refused the role because he found it unrealistic that a man of Bruce's size could beat him. This reason is so lame that it's almost certainly untrue, and the two men fell out because of other personal issues. But nevertheless, his version of the story makes it clear that Lewis had no doubt about the outcome of a possible fight between the two of them.
In short, personal testaments from contemporaries invariably intertwine with Hollywood legends. Memories make everything shinier, many people loved and admired Bruce (that's why they get interviewed) and many have a personal interest to make him look godlike, so part of the glow shines upon them, too.
Bruce Lee was a genius and physically a freak of nature. Probably, although you can never know, under the right trainer, he could have been a world champion. Could he beat the current UFC champion of his own weight category if he was teleported from 1972 to the octagon in 2022? No. He wouldn't have the experience, the stamina, the grappling skills. Could he be the world champion after training for 2-3 years under the best coaches? Well, why not?
In the end, perhaps it's fitting to close with another anecdote in which Bruce answers the original question directly. As the legend says, when John Saxon (one of the protagonists in Enter The Dragon) asked if he could beat Ali, Bruce replied, "Look at my hand. That's a little Chinese hand. He'd kill me."
