Who is to blame for infidelity - genes, metaphysics or unfaithful men?

It is typical of a mechanistic age that it should seek the scientific origin of a lapse it cannot even describe

Have I been dreaming or did I read somewhere that women who are unfaithful to their husbands are genetically primed to be so? And could I possibly have seen reference to Paula Yates in this context, the fact that she was the love child of Hughie Greene (something else I dreamed?) being adduced as reason for her tragic downward spiral into confusion and despair? Hughie was maritally itchy; therefore Paula, as repository of his genes, the same - that I think was how it went. Now tell me that Hell's Kitchen was gross! I feel tenderly to the memory of Paula Yates. Nothing personal. Never knew her; never met her. But I happened, though not an avid watcher of The Big Breakfast, to have seen her that notorious morning on the bed with Michael Hutchence. Scandalous, what? A milestone in the history of reality TV. Actually it upset me more than it scandalised me. You remember when Hamlet tells Horatio that all's ill about his heart? Well that was how they made me and indeed how they appeared to ma

Have I been dreaming or did I read somewhere that women who are unfaithful to their husbands are genetically primed to be so? And could I possibly have seen reference to Paula Yates in this context, the fact that she was the love child of Hughie Greene (something else I dreamed?) being adduced as reason for her tragic downward spiral into confusion and despair? Hughie was maritally itchy; therefore Paula, as repository of his genes, the same - that I think was how it went. Now tell me that Hell's Kitchen was gross! I feel tenderly to the memory of Paula Yates. Nothing personal. Never knew her; never met her. But I happened, though not an avid watcher of The Big Breakfast, to have seen her that notorious morning on the bed with Michael Hutchence. Scandalous, what? A milestone in the history of reality TV. Actually it upset me more than it scandalised me. You remember when Hamlet tells Horatio that all's ill about his heart? Well that was how they made me and indeed how they appeared to make each other feel. They seemed to be the victims of some undisclosed malady, some miasma of discontent and wrongness, of which the heart, as site of conscience no less than passion - and certainly as site of present hurt and foreboding as to any future - was the centre. Punch drunk, they appeared. High on recklessness. Giddy with their own too-muchness. Lost on a rolling sea of the infinitely doable.

Yes, well, that's what passion as prologue to infidelity is like, you might wish to tell me. We don't so much make decisions as lurch towards them, tempest-tossed. It was a funny old tempest, though, with Hutchence flirting girlishly with the camera, more the woman, you would have to say, than Paula Yates was. No disrespect intended. Let a man be as womanly as he wishes. I am in touch with my own feminine side at the moment, enjoying commerce with other men who are in touch with theirs. (No, we don't knit. We wrestle and discuss the offside rule, if you must know.) But in Hutchence's case, and of course I have only his demeanour and a smidgen of subsequent history to go on, it looked less like making contact with his own variousness so much as not knowing where any part of him began or ended.

And she, in his company, the same. If such is what our genes bequeath us, then I am not sure it is a predisposition to infidelity we are any longer discussing, more a longing for the consolations of chaos. In which case metaphysics is a better guide to our natures than biology.

It is typical of a mechanistic age that it should seek the scientific origin of a lapse (a dereliction? a necessity?) it cannot even describe. If we want to know where infidelity comes from, we should first of all know what it is. And that, I submit, is all but impossible, so susceptible to eccentric interpretation and wild imaginings are all manifestations of our sexual being. In the course of one week the hero of my new novel has gone from being called a sex maniac to being diagnosed as libido-drained.

Myself, I recognise neither as a discrete condition. It all depends where you're standing. One's man sex maniac is another's prude. One man's whore another's sweetest innocent. You will recognise the allusion. Othello.

The classic text on the subject of sexual unknowability.

Forgive my second reference to Othello in a month, but the play happens to be around. I saw a magnificent production of it the other night at London's new Trafalgar Studios, a theatre whose seating is so ill designed and uncomfortable that you leave looking like those creatures Othello wooed Desdemona with travellers' descriptions of - men whose heads grow beneath their shoulders. Whether mine will ever grow out again there is no knowing, but I am still pleased to have seen Sello Maake ka-Ncube's anguished Othello, his jealousy almost a rite of insulted masculinity, so palpable it is a bodily affliction, an anguish wracking his entire frame, and Antony Sher's wonderfully modernist master of ceremonies Iago, as much novelist as soldier, so curious to see how things turn out that you wonder whether they might turn out differently every night.

Indeed it is a mark of the production that you go on hoping until the end that tragedy will somehow be averted. But then is that not also the mark of the drama we call infidelity, that the seriousness of its consequences (which is another way of saying the truth of what it is) remains in doubt until the final act? This is not to argue that those "trifles light as air", which confirm the suspicions of the too easily jealous (as though everyone isn't too easily jealous), will always defy proof one way or another. After five acts of simmering detachment, Amanda Harris's heart-stopping Emilia finally protests Desdemona's innocence in language which even Othello can no longer withstand. But Emilia is no more genetic determinist than Desdemona was a whore. As it fell out, Desdemona did not do that of which Othello accused her; in other circumstances, though, who knows? "Let husbands know / Their wives have sense like them," Emilia muses earlier, her final words before Desdemona's murder. "They see, and smell, / And have their palates both for sweet and sour, / As husbands have." It is not a defiant, feministical assertion of a woman's right to sexual sport. It is too uncertain. She seems to be discovering what she thinks as she thinks it. And her conclusion - that husbands should use wives well, "else let them know, / The ills we do, their ills instruct us so" - has as much misgiving in it as threat. If women's infidelity turns out to be the consequence of men's example - if, if - it is to be regretted.

The fault, dear Brutus, is not in our genes, but in ourselves. That bit's easy to say. But who's going to tell us who ourselves are?