“It might.” Miriam pulled a face. “I might also twist an ankle. Which would be bad, in the middle of nowhere.”

“What happens if you try to go through with something on the ground?” Brill asked.

“I don’t.” Miriam refilled her glass. “It was one of the first things I tried. If you jump on my back I can just about carry you for thirty seconds or so before I fall over—that’s long enough. But I tried with a sofa a while ago. All that happened was, I got a splitting headache and threw up in the toilet. I don’t know how I managed it the first time, sitting in a swivel chair, except maybe it was something to do with its wheels—there wasn’t much contact with the floor.”

“Oh, right”

“Which says interesting things about the family trade,” Miriam added.

“They’re limited by weight and volume in what they can ship. Two and a half tons a week. If we open up ‘world three’ that’ll go down, precipitously, although the three-way trade may be worth more. We’ve got to work out how to run an import/export business that doesn’t run into the mercantilist zero-sum trap.”

“The what?” Brill looked blank.

Miriam sighed. “Old, old theory. It’s the idea that there are only a finite quantity of goods of fixed value, so if you ship them from one place to another, the source has to do without. People used to think all trade worked that way. What happens is, if you ship some commodity to a place where it’s scarce, sooner or later the price drops—deflates—while you’re buying up so much of the supply that the price rises at the source.”

“Isn’t that the way things always work?” Brill asked.

“Nope.” Miriam took a sip of wine. “I’m drinking too much of this stuff, too regularly. Hmm, where was I? This guy called Adam Smith worked it out about two centuries ago, in this world. Turns out you can create value by working with people to refine goods or provide services. Another guy called Marx worked on Smith’s ideas a bit further a century later, and though lots of people dislike the prescription he came up with, his analysis of how capitalism works is quite good. Labor—what people do—enhances the value of raw materials. This table is worth more than the raw timber it’s made out of, for example. We can create value, wealth, what-have-you, if we can just move materials to where the labor input on them enhances their value the most.” She drifted off, staring at the TV set, which was showing a talk show with the volume muted. (Brill said it made more sense that way.) “The obvious thing to move is patents,” she murmured. “Commercially valuable ideas.”