Walks over to a rock and places hand over it, says "see my hand? I want you to make a fist and smash my hand, as hard as you can"
The version I heard goes like this:
Black African complaining to White European "Why do you run the businesses here?"
European says "Let me show you that we're smarter. Here, see my hand? Hit it as hard as you can!", as the European places his hand on a tree trunk.
African goes to punch it as hard as he can, and the European pulls his hand away at the last second and the African smashes his fist into the tree and yells out in pain. Says "Okay, I understand."
Later, a second African asks the first African what happened to his messed up hand? First one says European was explaining why they're smarter. Second asks him to explain.
So the first African puts his hand over his face and says "Here, see my hand? Hit it as hard as you can!"