Jérôme Kerviel has had a relatively kind press thus far, certainly in France. But the notion that the rogue trader was some kind of romantic genius looks more and more far-fetched with every utterance he makes. His attitude to the risks he was taking with Société Générale's money veers between the cavalier and the completely self-deluded.

When first asked by his superiors about his huge unauthorised and loss-making positions last month, he responded with the immortal, “Yes, but it's nothing,” according to Le Monde. That must have gone down well as his managers wondered how on earth to unwind a billion-pound loss.

And his claim yesterday that he was using a martingale, a gambling technique favoured by 18th century French casino players, wins him no intellectual credibility whatsover. At its simplest, a martingale is a technique where the gambler on a 50-50 chance, such as the toss of a coin, doubles up each time he loses. His final winning bet is by definition large enough to offset all his losses plus a profit equal to his original stake.

Theoretically it is fireproof - except for one gaping flaw. The gambler has to have infinite wealth to ensure success, because a losing streak forces him to take exponentially larger bets. Moreover, the casino or counterparty has to accept ever larger bets too and has no gaming limits.

Mr Kerviel, who, aptly, was spending a weekend at the French casino resort of Deauville when summoned back to Paris to explain himself, seems to have completely missed the point about martingales, which have become a byword for betting strategies that ultimately lead to ruin.

Even the richest and most inbred of pre-Revolution French aristos eventually understood it was fool's gold. But not apparently Mr Kerviel.

Romantic? Perhaps. Genius? Absolument, non.

patrick.hosking@thetimes.co.uk

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