This German man is telling me about self-defense techniques. His pint has remained untouched at three-quarters full for ten minutes. Make to hit me in the face, he says, pointing to the middle of his glasses. I slowly move my fist toward his nose and he redirects my arm to the side, plants a mock punch to the cheekbone with his other hand. The stool creaks. These are things I teach, he says. I teach for twenty years, off and on. Give me your hand. I hold out my hand and he cradles my thumb between his thumb and forefinger, bounces the hand playfully up and down, taking its weight. To me it seems he has muscles in his fingers. The veins stick out in his forearm, which must be bigger than my bicep. His eyes are small, intense, staring at my hand, staring at me. If you can get hold of the hand, there is much you can do. He twists my arm in a way it shouldn't go and my whole body drifts toward the bar, a brief shock of pain registering in my elbow before he pulls it back. Or the other way. I slide off the stool and have to catch myself with my foot. He doesn't notice me wince, or maybe he does and he doesn't care. It's not about power, he says, it's about knowledge. What is it that he would have me know? Pain, perhaps. Or fear. To know what to do, how to move, he says. Redirect. Make a stabbing motion at my heart. I do what he says and he blocks my arm upward. Two legs of my stool leave the floor. Twenty years I teach this. I ask him, Have you ever been in a situation where you've had to use this? He leans over for his pint, takes a long swallow. Once, years ago. I am at a metro in Hamburg, I walk through a tunnel and two guys come from behind me. One tries to push me down. The other has a knife. I am so surprised I cannot think. They want to steal my bag but I will not let them. All I can do is fight them off, push them away as best I can, keep trying to go forward. I run, I block, push, dodge. He jerks his head one way, makes wild arm movements. I have no control. If I fall down I know they kill me. This goes on for several minutes. Somehow I make it to the end of the tunnel, and I yell. Finally they take off. I make sure that never happen again. He takes another swallow of beer. He nods, as if agreeing with something I've said. He steps off his stool and motions with his hands. Stand up, he says. Now I teach you something, yes?