What was he trying to prove?
The ''i got small hands..'' scene, where Jake La Motta asked his brother to hit him in the face, i didn't get what he was trying to prove. His brother asked him this too in that scene.
shareOne assumes the same thing he was trying to prove later in the ring against Robinson when he ceased to defend himself - that he's one stubborn, pig headed sonofabitch that just won't quit or go down whatever is dished out against him. And there's a solid dose of masochism mixed in as well. He's a man who chooses to be stupid.
"facts are stupid things" - Ronald Reagan