Hunter was frazzled, even by his own prodigious standards. He had stopped over in New York and reconvened with Saul before the two of them set out independently, Hunter to England to see what initiatives Lucy had come up with, and Saul to Paris to check out a Frenchman who claimed to have created a ceramic armour that was cheaper and more effective than those being developed by DARPA in the US or by the various Ministries of Defence around the rest of Europe. Before the two men could converge on Italy to explore further projects, Saul had dashed up to Edinburgh to meet John MacDonald, one of the world’s leading experts on inorganic life.

Hunter’s apartment was on the top two floors of a sudden, isolated skyscraper that had been driven, like a spike through the heart of Manhattan, well below the tall buildings of the Upper East Side and well above the tall buildings of the financial district. When Saul arrived, he had made some suggestive remarks about feeling tired out by his journey from California and his many meetings around town, expecting the usual line or two of coke, but instead Hunter asked him if he’d ever tried freebasing, snapping open a red leather briefcase, which turned out to contain two glass pipes and a small blowtorch embedded in red velvet moulds.

‘Wow!’ said Saul. ‘I’m not sure I’m ready to go down that road. Isn’t that like the most addictive thing in the world?’

‘The most addictive thing in the world is power,’ said Hunter, ‘if you have it, freebasing is just kidding around; without it, you can get addicted to stale doughnuts or rubber underwear.’

‘Or freebasing,’ Saul insisted.

‘Sure,’ said Hunter. ‘But when we finish with the pipe later tonight, I might go for a couple of months without even glancing in this direction again, because we’re brainstorming here, Saul.’

‘You’re the expert,’ said Saul, disinclined to argue openly with his overwhelming host. ‘Although Richard Feynman said that science is belief in the ignorance of experts,’ he couldn’t help adding.

‘That would make Donald Trump the world’s greatest scientist,’ said Hunter.

‘I guess he was thinking of people who have pushed existing knowledge to some kind of limit,’ said Saul, ‘rather than the ones who have turned their backs on it.’

Hunter loaded the pipe with a little pellet of paste.

‘Okay, okay, I’m sold,’ said Saul.