In my week

Show me someone who hates smoking at parties and I'll show you someone who's never been to a really good party

There are those sublime moments when the world throws you the chance to use a line and you catch it, one-handed, without looking, and pitch it back. Okay, so it was a stolen line: Saint Sharon of the Stones said it first in Diabolique, but the satisfaction went deep. We were feeling a bit yawny because we'd just sat through The Crucible. David was having a wazz and we were standing on the stairs by the ash-tray waiting for him.

We were discussing Daniel Day-Lewis. His appearance had saved me from falling asleep altogether by inspiring an attack of the giggles. It's that Irish thing. It's gone beyond a joke. It's fine wanting to be Irish: I have occasional urges to dig out me old granda's birth certificate myself. Artists don't pay tax, the bars are great and they've got the coolest capital city in the world after Valetta. But Dan's taken it beyond that: he's not content just with having the Nationality and developing a bit of a brogue: he is transforming himself into George Best. The similarity is getting stronger all the time: the scruffy beard, the bad haircuts, the highly-coloured nose. All the way through The Crucible, I kept expecting him to throw down his rake and shout: "for f***'s sake bring me a bottle of whisky and the shortlist for this year's Miss World".

Sam was going "Did you notice the miracle, by the way?"

"No. What miracle?"

"The teeth. Didn't you see? They kept changing. I mean, he had these nice, white, shiny English - sorry, Irish - middle-class teeth all the way through, and then when he got his soliloquy at the end they'd turned green and stumpy and he kept frothing through them."

"Yes. I did."

"And then, when they hanged him, he'd got the old ones back. There wasn't a gob of spittle when he was saying the Our Father."

"Well, you can't spit when you're praying."

"It's amazing," said Sam. "Redemption as orthodontist. I could have saved thousands of pounds on the boys' teeth."

"They'd have to sincerely repent first."

"Oh, they'd probably have done it like a shot if they'd thought it would make girls fancy them."

And then Taupe Woman came up. She had one of those "I've got children and I haven't got time for frivolity" haircuts, and an expression like someone who has just tried hundred-year eggs for the first time. "Excuse me," she said. "Mmm?" we turned to her. "Do you know what day this is?" she said. Sam and I had to think for a moment, days of the week not being so important to the self-employed. "It's Wednesday," said Sam. "No," said Taupe Woman. "It's National No Smoking Day."

A moment's silence. "How can you smoke, today of all days?" said Taupe Woman. "Sorry," said Sam. "Not my belief system. I drink during Ramadan, too." "Well, it's disgusting," said Taupe Woman, "a disgusting habit". "That," I said, "is a matter of opinion." I have had a long, loving, romantic relationship with the cigarette, and people trying to part me from my babies only makes me more determined to hang on to them.

Taupe Woman tried another tack. "Well, if you don't care about yourselves," she said, "you should think about the rest of us. Don't you realise your smoke can kill other people?"

Which was where I offered a prayer of thanks to Saint Sharon. I took a deep drag, looked her hard in the eye, exhaled. "Sadly," I said, "It's not a reliable method."

Year by year, National No Smoking Day has gone belly up in a cloud of nonentity and I've finally worked out why: it's because smoking is a taupe issue, not a health one. Show me someone who wants smoking banned in public places and I'll show you someone who has said to a colleague: "I'm really tired. We were up 'til one o'clock last night playing Trivial Pursuit." Show me someone who hates smoking at parties and I'll show you someone who's never been to a really good party.

I mean, think about the kind of mind that could say "I know. We'll take a group of people who are counter-suggestible enough to light up while watching ER, and we'll invent a day dedicated to not doing one of their most pleasurable activities. They'll all want to join in because they won't want to be left out."? Only a taupe person could think that a day posited on a negative could be a success. Days that work are based on positives: Armistice Day (promotion of peace); World Aids Day (promotion of the alleviation of suffering); International Women's Day (celebrating the existence of a superior species). Put "no" into a title and that's the reaction you get. I know half a dozen non-smokers who make a point of doing it on March 12.

Taupe Woman and I stared at each other across the gulf of nothing-in- common. Everyone needs role models, and I suppose it's inevitable that someone, somewhere would choose Anne Diamond. Sam pushed her glasses up her nose, smiled, said nothing. David emerged from the boys' room, and Taupe Woman's husband walked out behind him, pulling a woolly scarf from a Sainsbury's carrier bag. "We'd better go," he said. "It's after 11 o'clock. What did you think of the film?"

She followed him down the stairs. "Very good," she said. "And Daniel Day-Lewis was so convincing."