In a voice which led its owner back to the boardroom, Gilles went on: ‘History does repeat itself. Why? Because we don’t evolve much. If you had discovered a revolutionary, super-efficient way of reducing the energy price to two pence per kilowatt and that could be put cheaply into production in, say, China, what would be the best way to play it? You’d short Brent Crude and WTI futures with a seven-day duration, and then you’d leak to a known industry source, let the ripple start impacting energy price volatility everywhere, and sit back and watch the wisdom of the crowd take over. Because as soon as this invention is out there, everyone will want to get in on it. Two plus two still equals four, Jean, even today. The tidal wave of panic would cause mayhem in energy securities as the hedgies unwound positions in conventional oil and gas. The leverage through futures alone could be way more than a hundred to one.’

Gilles was right. This talk of money and power, it was a foreign currency to Dyer, like the notes on the Bookbinder’s ceiling. Marvar had probed the mystery of the depths, seen stars on the river bed. What had Gilles seen? Vaz de Caminha related how one Portuguese captain had listened patiently to a Tupi elder speaking ‘without anyone ever being able to understand him, or he us’. As so often when conversing with Gilles, Dyer felt much the same incomprehension.

‘What do you think of this shandy?’ he asked.

Gilles surged on. He knew he was boring Dyer, but he wouldn’t be deflected. He was addressing an international audience of bankers and patent brokers, and not Dyer across a rickety teak table laid for a meal that neither of them intended to eat.

‘What I’d like to know from you, Jean, is this: has Marvar made such a discovery? If so, where is the proof? You see, I need proof. Concrete proof,’ his fingers tightening again around the salt cellar.

‘Mon cher Ralph is convinced that Marvar, being Iranian, will have given his information to Iran. But Ralph is CIA, as doubtless you have realised, and like many intelligence officers his understanding of human nature is, let us say, pas trop intelligent. You have only to speak to Marvar for two minutes to realise his hostile attitude to the Mullahs. He wears that big coat, hoping it covers up everything, what he’s thinking, his amazing leap forward, his anxieties, but he can’t help it! He is naked in his heart. A bit like you, Jean, eh?