Boyd Tonkin: A Week in Books

Who would swap a zestful hour in "Extremistan" for a numbing lifetime in "Mediocristan"? Our movers and shakers in finance, the media and the academy have a penchant for "dangerous sports" with all the real risk removed. So it is, I'm afraid, predictable that their current wild ride of choice should be not a stock but a book: The Black Swan (Allen Lane, £20) by Nassim Nicholas Taleb. Once a refugee from Lebanon's civil war, later a Wall Street options dealer, Taleb is now the writer, professor and student of extreme random shocks who advises us always to expect the unexpected.

Taleb's wayward tract on "highly improbable" events and how they shape the world evidently appeals as much as a corporate hospitality box to high-flying readers. His universe doesn't creep or bunch in incremental steps; it breaks and jumps in epoch-making ruptures. Drastic bolts from the blue marked by "low predictability and large impact" come from nowhere to change almost everything, from the take-off of Christianity to Google, Harry Potter and 11 September 2001.

This vision flatters the all-powerful extremists of today's scoop-the-jackpot capitalism: those victors in a globalised economy where "a few take almost everything; the rest, next to nothing". It strokes the egos of those who fancy themselves superior to the common herd that clings to a docile belief in average scores and predictable patterns. On Taleb's wired planet, "mild" randomness now yields to its scary but exciting "wild" cousin. Booms will ride higher, busts dive deeper, as we all end up living in Extremistan.

"The superstars will always be there," Taleb concludes, when "bothered" by arguments in favour of the golden mean. His remedy for the "demoralising success" of the elite? "Religious beliefs." In its own way, the cult of the black swan says as much about a society in love with extreme inequality as the Sunday Times Rich List.

As he leaps like some superhero of the mind from Montaigne (sceptical, so good) to Plato (categorical, so bad), from Eco to Keynes, Taleb can be an immensely stimulating writer. And his book so neatly fits our winner-takes-all zeitgeist. His fans relish the notion of a market and a history ruled not by statistical mediocrity but by these dark and dramatic birds. Taleb himself has doubts, and says he detests the cruel nature that sets us adrift on this black-swan river of violent cataclysms: "as a humanist, I hate it. I hate most of the unfairness and damage it causes." Yet his macho rhetoric, spiked by shot after shot of sour invective, blankets his better ideas in a red mist.

Inside The Black Swan lurks an incisive and exhilarating shorter book on the weakness of "predictive" statistics and the decisive role of lightning-strike "outliers"; on the shortcomings of the Gaussian "bell curve" of distribution, and the relevance of Mandelbrot's famous fractals to Taleb's outlook. Taleb reveres Mandelbrot, but thinks his method breeds mere "grey swans" that allow us to half-predict "known unknowns". Yes, it was Taleb's views that gave Donald Rumsfeld his baffling mantra about "unknown unknowns".

The publisher's decision to let this book stray down every by-lane of anecdote and insult almost vitiates its value. It might not be a black swan, but it does sound like a screeching chimera: one third mathematical-historical lecture, one third score-settling stand-up routine, one third post-modern self-help manual. The bluster and the brilliance merge, each subtle thrust about (say) "the analgesic illusion of causality" matched by some chippy little outburst against philosophers, statisticians or other spawn of Satan. In any case, Penguin should have reined Taleb back to a non-random world where the December 2004 tsunami happened, beyond uncertainty, in the Indian Ocean and not - as he claims - in the "Pacific".