The David Niven secret was one of those razors that won't shave just beneath the nostrils

"Bloody hell, Laurie, I see you've got that new Gillette Mach 3," said Ben when he emerged from my bathroom for the fourth time in less than two hours. "The one they're always advertising on the television."

You can always tell when a man over 50 is trying to cover up a little prostate trouble but I was annoyed to see how well this crude diversion had worked among the half dozen guests who were still hanging around in the vague hope that what I'd described on the invitation as a "the first party of 1999" might still live up to its billing.

"You've not fallen for all that macho advertising, have you?" said Janet, one foot already in the stirrups of her hobbyhorse. "All that stuff about only real men being able to go through the performance barrier?"

I decided to go technical. "It's nothing to do with advertising. The simple fact is that the Mach 3 is a genuine advance on all previous razors. It's got three blades instead of the usual two and that means far less drag. And each blade moves around independently."

"But it's only a year since they were telling us that two blades was a major technological advance. I tried out that two-blade razor and it was no better than the standard Bic." When Geoff starts playing man o' the people you know it's time to start ringing for the mini-cabs. But there were still 12 months left in 1999 in which to pursue higher-minded conversations, so I persisted.

"I've never understood why men are so Luddite about advances in male cosmetics. Night after night I've had to sit around dinner tables and listen to women going on about how they've abandoned rubbing Immac cream on their legs because the hairs grow back too quickly, and how they've now moved on to the Boots microwave wax even though it hurts like hell when you rip off the cotton strips, and how they've all been thinking about having one of those Brazilian jobs where you rip out every wisp of pubic hair, and how that would be all right if only the hair didn't grow back all short and stubbly."

Janet was already cantering happily around the room. "Frankly, Laurie, I find that last remark insulting. Not only to me but to women in general. Why should any woman go through absolute agony in order to cater to pathetic old men who want to believe that they're having it off with a virginal 12 year old?"

From then on it was all downhill. Giles showed us once again how much he'd gained from his upper second in philosophy with some spirited logical claptrap about how it was conceptually impossible to distinguish between shaving one legs and one's vagina, and Geoff returned to the arena with a tortured argument about all men having paedophiliac tendencies and how much better it would be for everyone if they could gratify such desires consensually with a 45-year-old partner who'd had the full Brazilian than a girlie from the local playground.

What with one thing and another I never got around to telling anyone that the Mach 3 has one fatal defect. No matter how cleverly its three blades rise and fall across the surface of my face, it's almost impossible to use them to shave that thin line of bristles directly beneath the nostrils.

I only realised how serious the problem had become when I popped into the department to collect my mail this Wednesday. "Bugger me," said Sally, with considerably more affection in her voice than is normal at the beginning of an academic term. "It's David Niven."