Isaac sat back for a minute. To his surprise, he was loving this. The process of explaining his theoretical approach was consolidating his ideas, making him formulate his approach with a tentative rigour.

Yagharek was a model pupil. His attention was totally unwavering, his eyes as sharp as stilettos.

Isaac took a long breath and continued.

“This is major shit we’re dealing with here, Yag mate. I’ve been nibbling at crisis theory for arsing years. In a nutshell: I’m saying it’s in the nature of things to enter crisis, as part of what they are. Things turn themselves inside out by virtue of being things, understand? The force that pushes the unified field on is crisis energy. Stuff like potential energy, that’s one aspect of crisis energy, one tiny partial manifestation. Now, if you could tap the reserves of crisis energy in any given situation, you’re talking about enormous power. Some situations are more crisis-ridden or -prone than others, yes, but the point of crisis theory is that things are in crisis just as part of being. There’s loads of sodding crisis energy flowing around all the time, but we haven’t yet learnt how to tap it efficiently. Instead it bursts over unreliably and uncontrollably every so often. Terrible waste.”

Isaac shook his head at the thought.

“The vodyanoi can tap crisis energy, I think. In a tiny, tiny way. It’s paradoxical. You tap the existing crisis energy in the water to hold it in a shape it fights against, so you put it in more crisis . . . but then there’s nowhere for the energy to go, so the crisis resolves itself by breaking down into its original form. But what if the vodyanoi used water they’d already . . . uh . . . watercræfted, and used it as a constituent for some experiment that drew on the increased crisis energy . . . Sorry. I’m digressing. The point is, I’m trying to work out a way for you to tap into your crisis energy, and channel it to flight. See, if I’m right, it’s the only force that’s always going to be . . . suffusing you. And the more you fly, the more you’re in crisis, the more you should be able to fly . . . That’s the theory, anyway . . .

“But to be honest, Yag, this is much bigger than that. If I can really unlock crisis energy for you, then your case becomes, frankly, a pretty paltry concern. We’re talking about forces and energy that could totally change . . . everything . . .”

The incredible idea stilled the air. The dirty environs of the warehouse seemed too small and mean for this conversation. Isaac stared out of the window into the grubby New Crobuzon night. The moon and her daughters were dancing sedately above him. The daughters, smaller than their mother but bigger than stars, shone hard and cold above him. Isaac thought about crisis.

Eventually Yagharek spoke.