Flight of the black swan

Nassim Taleb is banging a glass against a table to demonstrate his notion of ‘anti-fragility’. ‘This glass is fragile,’ he says. ‘Vulnerable to nasty surprises.’ The glass survives his test. ‘Now, what’s the opposite of fragile? Not “robust”, because robust things don’t respond to any surprise, nasty or pleasant. To survive shocks and be adaptable means being “anti-fragile”.’ He believes that David Cameron should remake the British economy with this idea in mind. Economists come up with such theories and soundbites all the time, but with Taleb there is a crucial difference. When he speaks, the Prime Minister listens.

Since Taleb published his bestselling Black Swan five years ago, Cameron has been fascinated. A former derivatives trader turned New York University professor, Taleb emphasises the dangers of certainty — how economists, with all their computer models, get it so wrong. No matter how clever the plan, something unexpected — what Taleb calls a ‘black swan’ — can fly on to the scene and upset everything. The higher their debt, he says, the more companies are vulnerable to shocks. Taleb’s admirers saw the crash of 2008 as a staggering validation of his theory.

When Taleb held a public discussion with Cameron about debt two years ago, the admiration was mutual. Taleb described the then opposition leader as ‘the best thing we have left on this planet’. Even now he stands by that assessment. ‘I saw in him, then, someone who wants to rebuild society along the right model. Cameron was the first leader to grasp that deficits are dangerous.’ But this was two years ago. Our conversation moves on to what has happened since.

British economic output is forecast to grow by £100 billion over the next four years, I put it to him, but with a corresponding increase in the national debt of £360 billion.