Locked in a phone booth (or equivalent almost-touching space) with a chimp for a fight to the finish:
[ul]
[li]a man with a gun – has a fair chance if he shoots immediately and his shot strikes a “fatal area” (heart or adjacent blood vessels, brain). No certainty though, and a pretty high likelihood of both parties failing to survive the encounter no matter where the first (or second, or third…) shots strike.[/li][li]a man with a knife – has a chance. Not a good chance, not even a fair chance, but a slim chance. Still a fair likelihood of neither surviving.[/li][li]a man with a club or other bludgeon – has virtually no chance. Oh, a tiny hint of a possible chance, like a snowball surviving in hell and totally dependent upon a tremendously lucky first strike. But no better.[/li][li]a man with bare hands – has no chance at all. If he survives, it will be because the chimp got bored before finishing the guy off. And even then he’ll bleed out without immediate and herculean medical intervention.[/li][/ul]
I’ve handled (professionally) some “non-human primates”. Mostly the smaller ones, not the great apes. But I’ve been present when others have handled those animals, observed and assisted. And there are two additional aspects beyond the matter of pure strength already discussed. Which, I will reiterate, is overwhelmingly in the chimp’s favor.
The first aspect is speed. These creatures are quick. No, not just quick, but profoundly, stupefyingly, fast. So fast that one will grab, rip, tear, bite, and twist your extremity or your face or your genitals before you can draw back a fist for a punch. And then do it again, even while your punch lands. And again. And again. Along with their speed, these animals are incredibly lithe. They will block your strikes or avoid them while still causing damage to you. And woe unto you if you try the bear hug technique. Those canines will rip you to bleeding shreds. At the same time, that powerful, agile, lithe creature will easily frustrate your efforts to maintain a grip.
And finally, the way wild creatures respond to physical injury and pain is unlike normal human response. I work with wild animals every day, and see many with horrendous traumatic injuries. Unable to understand that our efforts are intended to help, they fight back with an intensity that is unimaginable to people who haven’t witnessed it. Pain seems not to exist for them. Creatures with a limb ripped from their body, bleeding out from a severed artery, will still use their remaining limbs and teeth with what seems to be all of the strength and intensity of an uninjured animal. In a life or death (to them) encounter with a human, wild animals expect no quarter – and give none. They fight to the literal last breath and last drop of blood.
In sum, it doesn’t matter what our fighter does to that chimp, except for putting a bullet into its brain. No matter what damage he inflicts, he will not slow the chimp down or reduce the intensity of its efforts. Since the damage ratio is so heavily in the chimp’s favor to begin with (every bite will cause copious bleeding and likely sever tendons and muscle groups, every grab and twist of an arm or a leg will break bones) even if our guy manages to cripple one of the chimp’s limbs, the damage ratio will only begin to approach parity. And meantime he is sans cojones, bleeding from 2 inch deep gashes all over his body, and struggling to use arms with fractured bones. Oh, and probably missing several fingers, too. The chimp will keep on keeping on, until the human isn’t resisting or the chimp gets bored. Then he’ll take a victory lap before sitting down to lick his own wounds. If, that is, he has any.