Affairs, explained Terry Keane, on Friday's Marian Finucane Show, mean love without responsibility. The nation sighed. What staggering insight: and timely too, because with women's massively increasing participation in the labour force, as figures showed last week, Irish lassies may soon have the money and opportunity to beat the lads at the game they tend to think they own. Social changes make it likely that more and more wives will soon be doing it, denying it, refusing it, or being hurt by it, whether they plan to or not. So however jaded we are of recent attempts to turn tacky adulteries into romantic epics (Anna Karenina they were not), affairs are an issue that just will not go away. In countries of similar economic patterns, but less recent religious observances, the fall-out from affairs is now reckoned to touch 80 per cent of families at some point, with rising rates of adultery by women. Wherever you're coming from, this represents a mountain of hurt and devastation.
Affairs, you see, thrive in conditions of opportunity, motivation, and money. Thus adultery, infidelity, whatever you term it, was traditionally a man's game. Some still think it a privilege - well, they would, wouldn't they? But with more women set to become players by engaging in the public world, this "privilege" may have to be shared.
Adultery is closely linked to work environments, hence the greater potential for women tomorrow. Wives and women partners can learn what is possible from chances husbands and male partners report. Some husbands like being sassy. Estimates of exactly how sassy they currently are look unreliable, because men reportedly overestimate their extra-marital sexual activity - to everyone except their wives.
Husbands travelling on business, for example, claim on average twice as many sexual contacts as do other men travelling on holidays, although some explain that they are unable to refuse female advances while in the company of their peers for fear of seeming "sissy", poor dears. Widely available data does indicate that approximately 40 per cent of men in wealthier countries will start to stray after only two years of marriage, and are particularly likely to begin at times when their ability to be sensitive to their wife's needs is tested, namely when their partner is under emotional stress during such times as pregnancy, early child-rearing or other major life events.
The wealthier or more powerful a husband becomes, the more he will have intimate sexual and/or emotional relations with women other than his wife. Husbands' adultery, therefore, reflects social status outside the family, or represents a bid for it, and appears to be respected as such. So cultures where men traditionally called the shots, like Ireland, will ban adultery in general but condone it for certain men, for whom it is viewed rather like a professional perk which accompanies their power positions.
Hence those fine words and fat arguments to explain why some - Charles Haughey - must be protected when they cheat, lest the unwashed public worry that if that is how they treat their life partner or commitment, they are hardly likely to behave more scrupulously to the rest of us. Haughey would have had trouble being re-elected if it were known he was repeatedly betraying his wife and family - not only by those with strict sexual ethics, but by the many more tolerant citizens who consider such behaviour unfair.
Myths about biological imperatives are still recycled to explain why responsibility for regulating and maintaining intimate relations remains the job of women, no matter what social changes happen. Wives are encouraged to blame themselves for their husband's adultery, because they have made too many emotional demands, devoted too much time to the children, "lost" their figures, or simply aged, and are fed those beliefs by hundreds of books and magazines designed to fuel their fear.
This holds true whether the wife was Diana, Princess of Wales; Jerry Hall, ex-partner of Mick Jagger; or an "older" woman like Margaret Cook, ex-wife of Foreign Secretary Robin, who bore the brunt of media attacks after he ended their marriage in an airport.
What is less often told is how adulterous behaviour can put everyone's physical health at risk, apart altogether from fine points like emotional well-being and family cohesion. The more sexual partners he has, the more his wife is likely to suffer from a sexually-transmitted disease, such as chlamydia, gonorrhea, and others linked to infertility, as well as to AIDS or cervical cancer, apart from less life-threatening syndromes like depression and alcoholism.
Perhaps adultery didn't hit the equality agenda before because wives formerly probably didn't think they were sassy enough to have another man. Few had either opportunity or money to pursue affairs, even if they possessed motivation. Wives were conveniently encouraged to please others rather than pleasing themselves, never mind being obliged to stay within the home, where they could repress their fantasies by reading Barbara Cartland, or imagining they were married to Clark Gable, as in Sean O'Faolain's story.
So they acted as ethical linchpins, as the family ban garda: husbands were considered as potential joyriders, ever-ready to pick up a pillion passenger unless the ban garda cried "halt". Such women usually stood by their cheating men even after it was untenable. They may have loved the bastards, sure, but with identities determined by his status, rather than their own, they had everything to lose if they unceremoniously chucked him out. Any wife who doubted that only needed to remind herself of her lack of statutory rights before heading straight back into the kitchen.
Family law is fairer now, although not entirely so to either sex. But if women who work in paid employment will now have opportunity and money, can we assume they will not have motivation too? The snarl in the smile of this trend is that husbands reportedly see affairs by wives as a fatal offence. The single biggest reason why men start divorce proceedings - women initiate the other 90 per cent - is wives breaking their vows.
"Mistress" has always conjured up the scent of peignoirs and slim lingerie; "wife", usually aka mother, wears the same old dressing gown with egg detritus on the collar, children hanging out of her and a demand for urgent payment of last month's mortgage in her hand. That image persists, despite world and workforce changes.
Love without responsibility - or a tautology devoutly to be wished? A husband who thinks he does his wife a favour by taking out the bins understands instinctively that a mistress expects her favours in the form of foreplay, preferably after a good bottle of wine. No wonder she's thinking of taking a lover. Tomorrow she may get the chance.