“This is what they call emergence, George,” he said. “From simple rules, applied at a low level, like the decisions made by the drivers on this damn road—and with feedback to amplify the effects, like a slowing car forcing a slowdown behind it—large-scale structures can emerge. It’s called self-organized criticality. The traffic always tries to organize itself to get as many cars through as possible, but it’s constantly on the point of breakdown. The jams are like waves, or ripples, passing back and forth along the lines of cars.”

It was hard for me to concentrate on this. Too much had happened today. Sitting in that lurching car, I felt as if I were in a dream. I groped for the point he was trying to make. “So the Order is like a traffic jam,” I said. “The Order is a kind of feedback effect.”

“We’ll get to the Order. One step at a time.” He wrenched the wheel, and we plunged out of the traffic toward a junction that would lead us back toward the center of the city.

We roared up Mussolini’s great avenue, hared through the Venezia, lurched left onto the Plebiscito. Peter rammed the long-suffering Punto into a few feet of parking space. I wouldn’t have believed it if I hadn’t seen it.

We got out of the car, locked it up, and made for a bar. I wanted coffee. Peter went to order while I found a table.

Peter returned with a bottle of beer. “You need this more than coffee, believe me.”

And oddly, he was right. Something about the heft of the bottle in my hand, the cool tang of the beer, that first subtle softening of perception as the alcohol kicked in, brought me back to reality, or anyhow my version of it. I raised the bottle to Peter. “Here’s to me,” I said. “And what I truly am. An appendage clamped to the mouth of a beer bottle.”

He had a Coke Light; he raised it ironically. “As a destiny, that will do,” he said seriously. “Just don’t lose yourself down in that hole in the ground . . .”

“Emergence,” I said. “Traffic jams.”

“Yes. And think about cities.”

“Cities?”

“Sure. Who plans cities? Oh, I know we try to now, but in the past—say, in Rome—it wasn’t even attempted. But cities have patterns nevertheless, stable patterns that persist far beyond any human time horizon: neighborhoods that are devoted to fashion, or upscale shops, or artists; poor, crime-ridden districts, upmarket rich areas. Bright lights attract more bright lights, and clusters start.

“This is what emergence is: agents working at one scale unconsciously producing patterns at one level above them. Drivers rushing to work create traffic jams; urbanites keeping up with the Joneses create neighborhoods.”

“Unconsciously. They create these patterns without meaning to.”