She said, "So what it comes down to is . . . you want to present the strongest possible case that deterministic systems like the Autoverse can generate a biology as complex as real-world biology -- that all the subtleties of real-world physics and quantum indeterminacy aren't essential. And to deal with the objection that a complex biology might only arise in a complex environment, you want a description of a suitable 'planet' that could exist in the Autoverse -- if not for the minor inconvenience that the hardware that could run it will almost certainly never be built."

"That's right."

Maria hesitated; she didn't want to argue this bizarre project out of existence, but she could hardly take it on if she wasn't clear about its goals. "But when it's all said and done, how much will this really add to the results with A. lamberti?"

"In one sense, not a lot," Durham conceded. "As you said, there can never be a proof. Natural selection is natural selection, and you've shown that it can happen in the Autoverse; maybe that should be enough. But don't you think a -- carefully designed -- thought experiment with an entire planet is a bit more . . . evocative . . . than any number of real experiments with Petri dishes? Don't underestimate the need to appeal to people's imaginations. Maybe you can see all the consequences of your work, already. Other people might need to have them spelled out explicitly."

Maria couldn't argue with any of that -- but who handed out research grants on the basis of what was evocative! "So . . . which university -- ?"

Durham cut her off. "I'm not an academic. This is just an interest of mine. A hobby, like it is with you. I'm an insurance salesman, in real life."

"But how could you get funding without -- ?"

"I'm paying for this myself." He laughed. "Don't worry, I can afford it; if you take me up on this, you're not going to be shortchanged, I can promise you that. And I know it's unusual for an amateur to . . . subcontract. But like I said, I don't work in the Autoverse. It would take me five years to learn to do, myself, what I'm asking of you. You'll be free to publish all of this under your own name, of course -- all I ask is a footnote acknowledging financial support."

Maria didn't know what to say. Lorenzo the insurance salesman? A private citizen -- not even an Autoverse junkie -- was offering to pay her to carry out the most abstract piece of programming imaginable: not simulating a nonexistent world, but "preparing" a simulation that would never be performed. She could hardly be disdainful of anyone for throwing their hard-earned money away on "pointless" Autoverse research -- but everything that had driven her to do that, herself, revolved around firsthand experience. However much intellectual pleasure it had given her, the real obsession, the real addiction, was a matter of putting on the gloves and reaching into that artificial space.

Durham handed her a ROM chip. "There are some detailed notes here -- including a few ideas of mine, but don't feel obliged to follow any of them. What I want is whatever you think is most likely to work, not what's closest to my preconceptions. And there's a contract, of course. Have your legal expert system look it over; if you're not happy with anything, I'm pretty flexible."

"Thank you."

Durham stood. "I'm sorry to cut this short, but I'm afraid I have another appointment. Please -- read the notes, think it all through. Call me when you've made a decision."

After he'd left, Maria sat at the table, staring at the black epoxy rectangle in her palm, trying to make sense of what had happened.

Babbage had designed the Analytical Engine with no real prospect of seeing it constructed in his lifetime. Space travel enthusiasts had been designing interstellar craft, down to every last nut and bolt, since the 1960s. Terraforming advocates were constantly churning out comprehensive feasibility studies for schemes unlikely to be attempted for a hundred years or more. Why? As aids to thought experiments. As sketches of proofs.

And if Durham, who'd never even worked in the Autoverse, had an infinitely grander vision of its long-term possibilities than she had, then maybe she'd always been too close to it, too wrapped up in the tedious contingencies, to see what he'd seen . . .

Except that this wasn't about long-term possibilities. The computer that could run an Autoverse world would be far bigger than the planet it was modeling. If such a device was ever to be constructed, however far into the future, there'd have to be far better reasons for building it than this. It wasn't a question of a visionary born a generation or two before his time; Autoverse ecology was an entirely theoretical notion, and it always would be. The project was a thought experiment in the purest sense.

It was also too good to be true. The Autoverse addict's dream contract. But short of some senseless, capricious hoax, why should Durham lie to her?

Maria pocketed the chip and left the cafe, not knowing whether to feel skeptical and pessimistic, or elated -- and guilty. Guilty, because Durham -- if he was genuine, if he honestly planned to pay her real money for this glorious, senseless exercise -- had to be a little insane. If she took this job, she'd be taking advantage of him, exploiting his strange madness.

+ + +

Maria let Aden into the house reluctantly; they usually met at his place, or on neutral ground, but he'd been visiting a friend nearby, and she could think of no excuse to turn him away. She caught a glimpse of the red cloudless sunset behind him, and the open doorway let in the hot concrete smell of dusk, the whirr of evening traffic. After seven hours cloistered in her room, reading Durham's notes for his Autoverse Garden of Eden, the street outside seemed strange, almost shocking -- charged with the two-billion-year gulf between Earth's equivalent moment of primordial fecundity and all the bizarre consequences.

She walked ahead of Aden down the entrance hall and switched on the light in the living room, while he propped his cycle against the stairs. Alone, the house suited her perfectly, but it took only one more person to make it seem cramped.

He caught up with her and said, "I heard about your mother."

"How? Who told you?"

"Joe knows one of your cousins in Newcastle. Angela? Is that her name?"

He was leaning sideways against the doorframe, arms folded. Maria said, "Why don't you come right in if you're coming in?"

He said, "I'm sorry. Is there anything I can do?"

She shook her head. She'd been planning to ask him how much he could lend her to help with the scan, but she couldn't raise the subject, not yet. He'd ask, innocently, if Francesca was certain that she wanted to be scanned -- and the whole thing would degenerate into an argument about her right to choose a natural death. As if there was any real choice, without the money for a scan.

Maria said, "I saw her yesterday. She's handling it pretty well. But I don't want to talk about it right now."

Aden nodded, then detached himself from the doorway and walked up to her. They kissed for a while, which was comforting in a way, but Aden soon had an erection, and Maria was in no mood for sex. Even at the best of times, it took a willing suspension of disbelief, a conscious decision to bury her awareness of the biological clockwork driving her emotions -- and right now, her head was still buzzing with Durham's suggestion for building a kind of latent diploidism into A. lamberti, a propensity to "mistakenly" make extra copies of chromosomes, which might eventually pave the way to sexual reproduction and all of its evolutionary advantages.

Aden pulled free and went and sat in one of the armchairs.