I love a man who thinks I'm funny

I MARRIED my first husband because I made him laugh: and I don't mean vice versa. I married him for other reasons too, of course - he seemed at the time charming, good-looking, intelligent and a good bet as a life partner - but when you are in your early twenties the same can be said of a fair number of men. What differentiated this particular young man was that I could reduce him to helpless laughter. I found this flattering, endearing and (a word we would never have used in the Sixties) empowering by turns.

I wish I could remember even one of my jokes from those far-off, palmy days. I would love to be able to turn it over now, examine it, decide whether it was really funny or just born of the sexual and emotional exuberance we shared. The letters he wrote which I kept (thrown out only this year in a great blitz of study-clearing) were more like a boarding school pupil's conscientious letters home than love letters; and never, ever funny.

He himself wasn't funny, either, but then nor really was I. Not even my most devoted friends would put humour at the top of the list of my qualities. Yet I have always been able to pull out the stops for a handful of people. Not with stylised jokes - I'm no good at those since successful joke- telling depends on memory and mimicry, whereas I get the voices and accents wrong and hang suspended for agonising seconds above the forgotten punchline. I have about three jokes, all decades old - the broccoli joke, the parrot joke and another that I can't now remember.

A few people, however, spur me to dizzying acrobatics of wit and verbal display that leave me astonished and them helpless. I had a boyfriend (as we called them once, long ago) who said, as we parted, 'Whatever else I forget about you, I'll never forget how much you made me laugh.'

A shared sense of humour implies all sorts of other things in common. It is not only the quickest route to mutual attraction - it works for friendships, too. One female friend used to grin the moment she set eyes on me; we were halfway to giggling already. Something in me set her off; something in her responded. If I could do it for everyone, I'd be Victoria Wood.

Perhaps this unknown trigger, to which (like cat mint) some respond and others are impervious, explains why private humour seldom survives on the page. I have been reading Nancy Mitford's Letters, most of them addressed to her sisters or a tiny circle of intimates. The same little spurs to laughter prod again and again. 'Are you shrieking?' she inquires coyly; or 'Shrieks]' Family in-words and phrases pepper her lines. 'Ay di me' for, presumably, 'oh dear me': a tic of reassurance in a chilly world.

Nancy Mitford's heartless lover, Gaston Palewski, for whom she suffered nearly 30 years of unrequited love, demanded that she should beguile him with laughter and gossip. She duly collected amusing tidbits like a magpie, to proffer in a glittering display of devotion. I once had an equally unrequited passion, though in my case it lasted a mere two years, and I, too, would collect gobbets of verbal sparkle in the hope of capturing his attention.

Private humour or a coded vocabulary is often the defining mark of a group. Lovers may use 'special' words (though a glance at the Valentine's Day messages shows just how recurrent and unimaginative those words usually are) to emphasise their bond.

The Devonshire House Set developed a unique pronunciation, lingering over consonants and hastening vowels; while the late-19th-century Souls changed the meanings of words - a 'dentist' for a heart-to-heart conversation - in order to baffle and exclude outsiders.

I am reading a book just now about the hearing children of deaf parents; but it doesn't explain whether or how the deaf 'tell' jokes or if they make each other laugh by quite different means. Do they develop a special adroitness in hand-signals, or are their facial expressions more exaggerated, more inventive, or faster? Do they mock the hearing world, 'telling' jokes about our big ears and loud mouths? Or would that be the deaf equivalent of racism?

I fear that I have devoted an entire column to humour that will not raise a single smile. Ah, but you should see the faxes and letters to my friends] They'd make you shriek]