I heard a description that has stuck in my mind ever since.
You are walking down the street in New York and you see a man wearing a black suit and a tall black hat, with a long beard and "fringes" dangling from his coat, who approaches another man walking toward him. He begins to speak accusations and confrontations to the man he meets, and then suddenly the man with the hat slaps the other man on the face, while he demands, vociferously, that the other man cease slapping him on the face (but the other man is not doing the slapping!). The man with the black hat continues to shout accusations, and slaps the other again, erupting with further demands that he stop slapping him (but he isn't slapping him). From an observational point, it appears that the accused is simply confused and doesn't know what to do about the situation. Finally, a foot officer interrupts, whereupon the man with the black hat claims that he was simply minding his own business when this other man walked up and started attacking him on the street, but the other man says, "no, that's what happened to me, not to him," etc. The policeman doesn't know what to make of it either, since he's trained to take the testimony of the first one to speak up, which was the man in the black hat.