MANILA, Philippines - Some of us are not well built for monogamy. Staying faithful to the same person requires talent and hard work. Some of us needs a hazard; we can?t reliably trust our emotions not to lead us astray and people we love do fall in love with others without our permission. Look up Jeremiah 17:9?the heart is deceitful and desperately wicked. Who can know it?

The infidelities of very important people and celebrities provide such a rich seam of amusement, they should be a genre of entertainment called ?current affairs.?

The call-girl scandal that felled New York Governor Elliot Spitzer, a.k.a. the Sheriff of Wall Street for his high-profile busting of insider-dealers, titillated us and prompted an outbreak of schadenfreude among those he put in the big house. With Silda, his wife of 20 years, by his side, his very public resignation was painful to watch: the spectacle of a sanctimonious, powerful politician?Client No. 9 of the Emperors Club?brought down by his rampant lust.

A classic of the genre was the process to impeach Bill Clinton, when he was asked if he had sex with Monica Lewinsky. ?I did not have sex with that woman,? he said, parsing his words. Monica?like the rest of us?did not have the, er, full measure of him either.

An Inca lord kept 700 women in his household for his pleasure. Chinese emperors routinely kept a queen, three consorts of the 1st rank, nine wives of the 2nd rank, 27 wives of the 3rd rank and 81 concubines. 16th century harems of the maharajahs had hundreds of women.

Ancient Romans kept courtesans for pleasure; concubines for the day-to-day needs of the body and wives for producing heirs. The Old Testament is so full of begetting, it makes you dizzy just to follow the shameless trail of seed-planting.

Genetic flaw

If infidelity is the original sin, why does it still have the power to shock and destroy us? Is it better to get hurt by the truth than comforted with a lie? Perhaps it?s a chromosomal malfunction, as true for men as for women, for studies show that 47 percent of married men have affairs and 35 percent of married women do, although as the actress Eileen Atkins points out, ?Women are more successful at infidelity than men; they are better liars.?

And yet Swedish researchers recently discovered AVPR1A, the so-called love-rat gene, in a study of 500 sets of twins. They found that some men appear not to process vasopressin, a brain chemical linked to bonding. Men with this genetic flaw found it harder to remain monogamous and faithful to their partners.

While infidelity is the utter betrayal of trust, it?s not always the end of love. You?re beguiled by someone at work whose propinquity is hard to avoid; a fellow passenger on the train with whom you flirt with intent, as you exchange news headlines; someone you brush up against in a crowded bar; your wife?s best friend, who shows more cleavage and laughs louder at your jokes.

Your spouse has lost interest in sex; you?re bored; feel trapped in a joyless relationship?any number of reasons for perfidy, the frisson of sexual excitement and of surrendering to something illicit, of thinking that romance and sex?it always comes down to sex?are happening elsewhere to other people, and why shouldn?t you have some of it, if you can be discreet?

The lure of an affair is so overwhelming that we?re not all like the divine Paul Newman, who argued ?Why go out for a hamburger when you can have steak at home??

Wearying

Sometimes there?s no explaining the demons that tempt us; sex is a powerful drive and love?which is what you want to feel about what you want to do?magnifies everything.

?The awkward fact, which most people somehow prefer to ignore, is that men often prefer sex without a relationship. Perhaps that?s wrong, but one must concede that relationships, particularly marriage, can be wearying; sometimes a man just wants time out,? wrote the journalist Minette Marin.

And some wives are only too glad to have the heat taken off them. ?So heavy is the chain of wedlock,? wrote Alexandre Dumas, ?that it needs two to carry it, and sometimes three.?

The late Sharon Tate?s advice for a happy marriage? ?Roman [Polanski] lies to me and I pretend to believe him.?

Most women will quarrel with that and blame wives who fail to make their husbands feel satisfied. But Gary Neuman in his book ?The Truth about Cheating,? suggests that for a woman to keep her man, she should always forgive him, provide sex on demand and be grateful that he provides for the family, even if she?s the main breadwinner.

You?d expect this antediluvian dross from a man, but not from
Mira Kirshenbaum, who has been counselling troubled couples for 30 years. She provoked controversy with her book ?When Good People Have Affairs.? She writes: ?Owning up is totally destructive. Honesty is all very well, but not at the price of your partner?s trust and peace of mind. There are exceptions: if you haven?t practiced safe sex or if discovery is imminent.?

Feeling guilty

Twenty years ago, most affairs, according to statistics, lasted about three years before they fizzled out; these days they last about six months.

Most people are handsomely equipped to fail in their furtive indiscretions. If you haven?t been found out, give it fire and time and it will burn itself out.

?It?s because they?re good people that they lie awake feeling guilty, agonizing about how to avoid hurting people they care about. An affair might be a mistake, but it?s also an insight: something?s missing, something?s not working right, something needs to change,? Kirshenbaum writes.

It might save your marriage! If sly phone calls, saucy text messages and a post-coital glow do reveal the treachery of your heart, there will be weeping and wailing, venting of spleen and vitriol, grief. You hope there will be forgiveness, because the consequences are unthinkable.

It?s true that some hours weigh against an entire lifetime, but you must measure what little you have gained, by what you might lose forever.