Close-up: Nassim Nicholas Taleb

The author comes to Britain to defend 'the most-bought, least-read book' of our times

You might think the writer of a book that topped Amazon's non-fiction chart throughout 2007 would be keen to get cracking on a follow-up. Not so the Lebanese-born author of The Black Swan, Nassim Nicholas Taleb. "It took me 20 years to write," he says. "I keep writing, a little bit every day, until I get bored. I don't like the constraints of having to do another book, so I only write when it's pleasurable."

Taleb, 48, who moved to America after the Lebanese Civil War, can take his time: he is in the luxurious position of having a second successful career as a senior trader on Wall Street, having gained an MBA from the prestigious Wharton School at the University of Pennsylvania.

In Taleb's lexicon, "black swans" are the rare and utterly unpredictable events which shape much of our history, and which we try to explain in hindsight. "Both world wars and Christianity are black swans," says Taleb. "As are the internet and 9/11."

The term "black swan" has actually been around since Roman times. It was originally used as a metaphor for something non-existent – as all swans were believed to be white. When early settlers in Australia (the black swan's natural habitat) first saw such a creature, it forced them to rethink what they thought they knew: the first "black swan moment".

Thanks to the book's success, Taleb spends only half his time at home on the outskirts of New York and the other half on the road: he arrives here this week to lecture at Oxford University and LSE.

"I was surprised by the book's success," he admits. "The Economist said it was the most-bought, least-read book since A Brief History of Time but that's not true: people do read it, because of the stories." n

'The Black Swan' (Penguin, £8.99) is out now