On my way home I came to a T-intersection; the light was green; I turned right. Across the intersection, idling at the light, stood a black, late-model imported sedan. Within sat two young men, the driver and his front-seat passenger. Each wore a white shirt and dark, straight, barbered hair. They might have been members of the same church, or something. Strangely, they were clutching each other in an awkward embrace.

"Boys, boys," I chuckled, "save it for home!"

As I swung past I saw theirs was a desperate kind of clinch - animated, tense, full of energy. Then I knew: they were fighting. Straining, striking, flailing, faces grimacing in pain, they were solving some dispute in the most atavistic way, but inside a car in the middle of traffic.

I saw all this in a matter of seconds, and then I had driven past. The unexpected surprise of it made my stomach lurch, as if I had fallen through a trapdoor. The suddenness of it was disorienting; the face of everyday life had been ripped away to reveal an angry skull beneath. Intimations of doom hung in the air.

Locked together in the dark metal box, the young men's lives had collided in a violent, close-quartered, cloying, clawing, intimate encounter. Once begun, such a fight afforded no retreat: backs to the doors, little space between them, they had no recourse but to slug it out. The cab of an auto is a tiny place in which to decide a quarrel.

What had set it off? A disagreement over a woman? Trouble at the office? An argument about money? I would never know. What if I had honked my horn? Would that have stopped them? Was it any of my business? I had the odd notion that they'd have ceased brawling, looked at me, then spun the car and chased after me.

In a megalopolis of several million, TV stations daily report incidents of violence: a stabbing here, a shooting there, a drunken altercation with police, an arson fire. Despite the airplay, the amount of fighting is pretty small when you consider how often we jostle each other in the city. It's a tribute to civility that we aren't at each other's throats constantly. Instead, the worst trouble most people get is a raised voice or finger.

But now and then that civility is stripped away, as with the fighters in the car, and we must watch as humans break the most basic codes of society, violate our sense of propriety, and shove our own worst natures in our faces. Time stops, schedules are forgotten, and for a few startling moments we're outside our carefully built shells of complacency. Instead we find ourselves on a different plane where a dry, cold wind blows and hope is blasted and we stand at the edge of the world, looking down.