The next morning – Saturday – I had recovered enough to explain the red patch under my eye and put a defiant, rational, angry spin on the whole business. I made some edits to the events, which helped. I felt it was my right, as victim and star witness.

One housemate was insistent that I should report the incident to the police, in the teeth of my insistence that I didn’t want to, and that the police wouldn’t bother doing anything, and that the men would never be caught even if they did.

It doesn’t matter, Jack, they need to know for the statistics. That’s important. The statistics, he kept saying. You have to report it for the statistics.

The following Monday, face showing a jaunty bruise, I was received as a hero in the Divider office. A crowd formed to hear what had happened (director’s cut). Again I heard about the importance of police statistics. In the end I did report it, but only to get a crime number that I could use to claim insurance for my lost phone. The statistics were served.

Among the most sympathetic of my colleagues was one of the women I had unsuccessfully flirted with at the party. Her name was Elise.

Divider closed in 2009. We had both moved on by then, Elise and I, and moved in together.

‘I’m not sure that’s true.’

Pierce tilted his head, interested. ‘What isn’t?’

‘What you just said,’ I said. ‘About mugging being “the most primal urban experience”. I mean, it’s a primal experience all right, but how urban is it?’

Pierce leaned forward. He was engaged. The eyes were back at full beam, the brow locked, the self-pity gone. ‘It’s completely urban. It is a crime almost unknown outside cities.’

‘Sure, I know, but—’

‘The city arose as a place of concourse and trade,’ Pierce said, barging on, in full talking-to-an-audience mode. ‘Mugging is a kind of trade, conducted by force, imposed on you, in a place made for trade. It’s by definition in the street, or at its edges, and unlike a lot of violent crime it’s mostly stranger-on-stranger, and therefore thrives where there is the highest population of relative strangers. You are brought into sudden, total contact with one of your fellow citizens, people you might be highly unlikely to encounter otherwise; it’s an extraordinarily powerful and meaningful interaction, transcending some boundaries, but operating entirely within others, urban in its—’