Naturally I asked him about his life since school - and by life we mean two things only, love and money, one being represented by marriage and kids and the other by work. He told me he worked computerishly for a bank and hated it with every fibre of his being - and I said I was sorry to hear that - and that he was the father of two girls aged 16 and 18 - and I congratulated him - and that he and their mother had parted ways - and I said I was sorry to hear that too - though in truth I was still marvelling at this young man being the father of daughters older than he'd been when I taught him.
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"In the Reproductive Handicap," I said, "you were out of the gate pretty fast."
"I was keen," he said.
And then it struck me that not only were his daughters older than he had been when I had taught him, but he himself was now older than I had been when I had taught him and I said as much and we both said gosh, how fast time passes, which it does, of course, when one looks back on things, though when one merely looks around it's hard to spot the damn thing moving at all. Our only evidence is still the passage of the sun across the sky and the hands around the watch dial.
It was then that he said, "I had a dream."
Now I don't know how you react to people telling you they had a dream, but I normally say, "Oh really, how very interesting," and then I point at something behind them and when they turn to look I run. Because other people's dreams, well, to put it in the mildest possible terms, bore me.
But as I say he was a nice chap and a smart one and I trusted him not to bore me so I invited him to go on.
"The dream," he said, "was a nightmare. They made a law forbidding the naming of days."
"I see," I said.
"I doubt you do," he said. "The names of days are vital to our sanity."
"How so?" I said.
"We may think we don't like Mondays, but even the worst Monday is better than not knowing that it's Monday. If the days have no names we are lost. No days mean there are no weeks or months or years and we lose all sense of when and who we are and we become like toy boats on the huge and indivisible ocean that we call time, just bobbing up and down with no reason, direction or meaning. Everything loses significance.
"By naming days we tame the ocean. We carve it up and count and measure it, and thus we fool ourselves we've got it under our control. We haven't, but it makes for peace of mind.
"In my dream I protested. I sang the names of the days out loud each morning from the window of my flat. The authorities boarded up the window to silence me, so I climbed onto the roof to announce the days through a loudspeaker, and they sent police dogs up to haul me down and they arrested me.
"In prison I scratched the name of each day into the wall with bleeding fingernails but they came in and blasted it off. And I was beset with a sense of utter impotence and futility and existential terror, but they just laughed at me. I can't remember how it ended. All I can remember was their laughter and the terrifying sense of emptiness. That was my dream," he said.
"Gosh," I said and then I was quiet and I wondered whether I should tell him about the dream I'd had myself the night before in which I'd been invited to MC the opening of the Tokyo Olympics, but Ivanka Trump had stolen my dinner jacket. But with an unusual display of restraint I decided not to.