The wise man was no fool. He knew that I would buy what he had to sell

"Time is elastic," said the man in the pub to me. "Time is elastic. Know what that means?"

I try to discourage people in pubs from talking to me. The method I choose is to engage them in conversation and bore them so much that they just go away.

"Yes, I know what it means," I said.

This surprised him. What I was meant to say was something like, No, I have no idea what it means, please tell me the mystery of time, o wise stranger in a pub ...

"Go on, then, tell me," he said, "tell me what it means that time is elastic."

"It means that after a while time goes hard and wrinkled instead of being supple and stretchy, and breaks when you pull at it."

His face spread into a smile when he realised that I was trying to be funny. People who are trying to be funny can always be defeated by people who are trying to be boring.

"No, what I mean by time being elastic is that people no longer live in the present. We live in the past and future simultaneously."

I said nothing, meaning that he had not got to the interesting bit yet.

"We do not think it odd to be planning for someone's birthday in two week's time and at the same time reading a history of World War I."

"These days you wouldn't be reading a history of World War I," I said. "You'd be reading a novel about it. Have you noticed that everyone from Sebastian Faulks to Pat Barker is writing novels about World War I? And nobody is writing them about World War II? Why do you suppose that is?"

For a moment, he paused, and then decided it would be more fun to go on with his own train of thought.

"Anyway, you get the point that we exist in the past and future as well as the present. For instance, the Millennium is in the future - but it celebrates the past as well! You couldn't have AD 2000 without AD 0!"

He was interrupted at this point by the landlord leaning forward, tapping him on the shoulder and pointing to a big notice behind him. It was headed "UP-TO-DATE SCHEDULE OF CONVERSATIONAL TOPICS WHICH ARE TOTALLY BARRED FROM THIS PUBS and on the list, along with Princess Diana, The Full Monty, The Eurovision Song Contest and Dame Elton John, it said The Millennium.

"Put it another way," said the man. "We are constantly preoccupied with what has not yet happened or with what is over and done with. We know that next summer will be warm and the grass will grow ..."

"Maybe, but I don't let that govern my behaviour," I said.

"You should," he said. "You should be booking your summer holiday now and putting your lawn mower in for an overhaul."

Uncanny. It was exactly what my wife had said the day before.

"Go on," I said, getting interested despite myself.

"Now, people get their mowers serviced in the winter because if they wait for summer, they will find the garden machinery people are all busy servicing mowers. So they get their mowers serviced in winter for the summer to come. Right?"

"Wrong," I said. "If everyone does that, then they'll find that the garden machinery people are all busy in winter, and free in summer."

"Nowadays we live partly in the past and partly in the future," he said, ignoring me. "We are used to TV and radio repeats. We are used to seeing sports highlights being immediately repeated in slow motion. We are used to seeing new films come out a year later as a new videos. We live in an age of deja vu. Time is becoming elastic ..."

"I have an uncanny feeling that I have heard parts of this conversation before somewhere," I said.

"Give you another example," he said. "When summer comes, we all say that it's Pimms time, but when we go to the shops to buy some Pimms, there's none there. Why not?"

"Because it's Pimms time, and people have bought it all."

"Exactly. The right time to buy Pimms is in wintertime!"

"That's the first sensible thing you've said," I said. "Next time I go into a wine shop, I'll stock up on Pimms."

"No need," he said. "I've got a case in the car. I'll let you have it at a very advantageous rate."

Somewhat bemused, I found myself the owner a few minutes later of a case of Pimms.

"It's a joy to watch him at work," said the landlord to me. "What a salesman."

As I left the pub, lugging a crate of Pimms, I overheard the man saying to a couple sitting by the fireplace, "Time is elastic, did you know that? Yes, time is elastic! Know what that means?"

I had an extraordinary feeling that I had heard this conversation somewhere before, and that I didn't want to hear it again.