When it comes to sex — as with everything else — it is important to set out one’s terms. Are men better than women when it comes to writing erotica? Well, what do you mean by “better”? And, come to think of it, what do you mean by “erotica”?

I might as well start with a story — the best way to start nearly anything, and certainly the best way when it comes to sex. For sexual attraction, just like a story, has a beginning, a middle and (ah, alas) an end. I’ll tell you the story of the sexiest thing that ever happened to me: and I’ll just have to hope that my husband forgives me.

It was a long time ago; I was on a train. I was travelling from Paris to the south, and even though I didn’t have much money I had bought myself a first-class ticket; I imagined that a comfortable seat would go a little way to soothing my broken heart.

I had left my lover in Fontainebleau — and I knew then, though I did not want to admit it, that although we had not parted on bad terms, things would never be the same between us again.

I had a book to read; it was Jeanette Winterson’s The Passion, as it happens, and as I read about a woman who put her heart in a box I leant my head against the window glass and wept. The pale china blue of the sky, the green-gold of the late summer countryside, blurred by speed, blurred by my tears. My tears were silent, but they would not cease.

So I did not notice when the gentleman across the aisle from me rose from his seat, as he must have done. I noticed him only when he returned, from the buffet car, where he must have gone, for on my little seat-back table he set a cup of coffee. An espresso, dense and dark, laced with foam, a breath of steam rising from its surface.

He didn’t speak to me or even pause, but sat right back down in his seat, and when I turned to look at him in grateful amazement he gave me a small, warm smile and went back to his Le Monde. He was older than me by some years; he had dark hair and was elegantly dressed; I would not have called him handsome, but neither would I have said that he was not.

I didn’t really drink coffee in those days; but I drank that cup to the last bracingly bitter drop. Life goes on, said the taste in my mouth: there are more adventures ahead. If you want to know what happened next, I’ll tell you: nothing.

Sometimes the beginning of a story can be enough; a potential encounter as gratifying and memorable as the consummation of flesh. Restraint as erotic as abandon; denial and delay are sensual, temporal bonds.

That’s my story; it won’t be yours. Men and women alike write about sex to try to understand it better: that we have not gained in understanding in the many, many millennia we have walked upon the Earth is surely a cause for joy rather than regret. How delightful that the matter should be so mysterious that we must try and try again . . .

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