True, there are many jokes about sex, but few very funny ones. And as it emerges from taboo, the tittering may even one day cease altogether (except under the covers, where it is unavoidable). No, the real and enduring human comedy is love. In our march to the grave, it is still the banana skin to slip on. Love by definition overrules reason, and its blinded followers rush into the most ludicrous situations. In outline, after all, Othello's insane jealousy, worked up over a missing handkerchief, is farcical. It is Shakespeare's generosity that he grants to the doltish moor a tragic grandeur, at least in death.
Tragic grandeur is putting it a bit high, but Channel 4's Cutting Edge documentary Love (9pm, 25 June), was tactful enough to keep the smirking to itself as it investigated the impact of love on three perfectly nice people. Quietly going about their lives, they might nevertheless recognise Ted Hughes's line about how love flew into his life "like a hawk into a dovecote".
The first of the fools for love was young Joanne from Poole. She was working in her mother's pub in Hartlepool when Martin walked in, the man of her nightmares masquerading as the man of her dreams. On the first date, so-handsome Martin explained that he was a secret policeman, who had previously worked under cover in the army in Northern Ireland, where he had watched his best friend die. Martin had a fine line in romantic soulfulness. Promising that he would take her back to live in his beloved Lake District, he set himself the knightly quest of climbing the region's highest mountain and finding a rock from the top just for her. "I thought, what kind of guy does that? He must be wonderful," enthused Joanne.
Wrong answer. The kind of guy who did that (or said he did - I wonder from what height above sea level that stone was gleaned) was a pathological conman. When he whisked Joanne back to his insalubrious council home, he muffled her shock at its squalor (sink estate, no oven, no fridge) with a fantasy about the importance of living amid the people whose drug dens he raided. "I thought he was very brave," said Joanne, who also thought that he was due £100,000 compensation for a professionally incurred back injury. The truth, as it emerged months after she had moved in with him, was that he had never been in the police, the army or Northern Ireland, but was no stranger to income support. Ricocheting from him into another rotten romance, Joanne is now a single mother in Dorset, unable, except in her twins' case, to trust anyone again.
The second story was more troubling still. It starred Wendy, whose third marriage, in her fifties, was to David. This time, she was convinced, the fairy tale had come true - and videotape of their honeymoon in the Dominican Republic certainly looked like the kind of romantic fantasy sold between embossed covers at airport bookstands. "I never wanted for anything," she smiled suggestively. Eighteen months on, her son played her a tape recording of David putting out a contract on her life: "You can't miss her. She's a fucking great thing. Fat pig . . . Make sure she's fucking dead. I don't want to end up looking after a fucking vegetable . . . Plough straight into her. Knock her down . . . I'm easy, mate, I can soon find another wife."
The violence of his language was shocking, but not as shocking as discovering that Wendy still loves David, currently serving eight years for soliciting her murder. The cameras caught her coming out of Parkhurst after another Thursday visit, still a teenager in love, telling herself that they were simply going through a "bad patch".
We were stopped from concluding that people who seem too good to be true invariably are, however, by the last story. Jon, a lowly sort of office bod, fell in love one day with a beautiful but mysterious black co-worker. After a year of meetings at the telex machine, Stephanie finally agreed to a date. For two and a half years, he scarcely got beyond ordering her coffee and touching her hand. Stephanie was always having to leave early: there were difficulties at home, a domineering uncle.
At the very least, she's married already, I thought. Then 22 minutes in, Stephanie suddenly appeared on camera as radiant as Jon had promised. The mystery of her background was that she was a Ghanaian princess, a yarn so unlikely that even Martin would have baulked at spinning it, but in her case was true. They have now been married for 12 years and have five children for whom the adjective "beautiful" is, for once, no exaggeration.
Sue Bourne's film had the good sense to let the three tall stories unfold with minimum interference or interpretation. In each case, they were related by the victims themselves, but subtle editing was responsible for the beautiful pacing that provided, for instance, a cliffhanger before every advert break. The camera was left to sniff around the locations concerned, searching for atmosphere-inducing details. The close-ups of waves lapping against pebbly shores and neon signs winking above dark, satanic coffee shops could not conceal that this was an illustrated radio programme. A good radio programme, however.
Andrew Billen is a staff writer on the Times