‘“Well,” he said, wasting no time, “the first thing to be said is that I lived a blameless life until 1982. Entirely blameless. If you were to plot my life along a graph, morally speaking, you would see a very flat line for the first 37 years, then one very sharp spike in the middle, followed by another completely flat line right up until the present day.”

“Given,” I said, “that that seems to be the case – ”

“Oh, it is the case,” he said.

“Well, I thought we might try to talk about why it happened.”

“Fine,” he said. “But you must remember that this was a financial situation. It wasn’t what you might call irrationality, or lack of control. There was a problem to be solved. And you might well ask, well, why solve it using this particular technique? And that’s a legitimate question. But it wasn’t an act of madness.”

After the call ended, I sat on the bench, staring at the words I had scribbled in my notebook as we spoke. I circled the word “problem”, and then the word “technique”.’