"Come on," I say, "let's go see Linn and Vhora."

"Sure," she says, partly letting go. "But Robin, isn't it obvious what you need to do?"

"Huh?"

"About your problem." She taps her toe impatiently. "Or haven't the therapists been giving you the hard sell, too?"

"You mean the experiment?" I lead her back into the Green Maze, cueing my netlink for another firefly. "I was going to say no. It sounds crazy. Why would I want to live in a panopticon society for ten or fifty megs?"

"Think about it," she says. "It's a closed community running in a disconnected T-gate manifold. Nobody gets to go in or comes out after it starts running, not until the whole thing terminates. What's more, it's an experimental protocol. It'll be anonymized and randomized, and the volunteers' records will be protected by the Scholastium's Experimental Ethics Service. So—"

Enlightenment dawns. "If anyone is after me, they won't be able to get at me unless they're inside it from the start! And while I'm in it I'll be invisible."

"I knew you'd get it." She squeezes my hand. "Come on, let's find these friends of yours. Do you know if they've been approached, too?"

WE find Linn and Vhora in a forest glade, enjoying an endless summer afternoon. It turns out that they've both been asked if they're willing to participate in the Yourdon study. Linn is wearing an orthohuman female body and is most of the way out of rehab; lately she's been getting interested in the history of fashion—clothing, cosmetics, tattoos, scarification, that sort of thing—and the idea of the study appeals to her. Vhora, in contrast, is wearing something like a kawaii pink-and-baby-blue centaurform mechabody: she's got huge black eyes, eyelashes to match, perfect breasts, and piebald skin covered in Kevlar patches.

"I had a session with Dr. Mavrides," Linn volunteers diffidently. She has long, auburn hair, pale, freckled skin, green eyes, upturned nose, and elven ears: her historical-looking gown covers her from throat to floor. It's a green that matches her eyes. Vhora, in contrast, is naked. Linn leans against Vhora's flank, one arm spread lazily across her back to toy idly with the base of the fluted horn that rises from the center of Vhora's forehead. "It sounds interesting to me."

"Not my cut." Vhora sounds amused, though it's hard to judge. "It's historical. Premorphic, too. Sorry but I don't do ortho anymore, two lifetimes were enough for me."

"Oh, Vhora." Linn sighs, sounding exasperated. She does something with one fingertip near the base of the horn that makes the mecha tense for a moment. "Won't you . . . ?"

"I'm not clear on the historical period in question," I say carefully. To be perfectly truthful, I'd deliberately ignored the detailed pitch Piccolo-47 mailed me until Kay pointed out the advantages of disappearing into a closed polity for a few years, because I was totally uninterested in going to live in a cave and hunt mammoths with a spear, or whatever Yourdon and his coinvestigators have in mind. I don't like being taken for a soft touch, and Piccolo-47's attitude is patronizing at best. Mind you, Piccolo-47 is the sort of self-congratulatory, introspectively obsessed psych professional who'd take any suggestion that their behavior displayed contempt for the clients as projection, rather than treating it as an attempt to work around real social deficiencies. In my experience, the best way to deal with such people is to politely agree with everything they say, then ignore them. Hence my lack of information about the exact nature of the project.

"Well, they're not telling us everything," Linn apologizes. "But I did some digging. Historian Professor Yourdon has a particular interest in a field I know something about, the first postindustrial dark age—that would be from the mid-twentieth to mid-twenty-first centuries, if you're familiar with Urth chronology. He's working with Colonel-Doctor Boateng, who is really a military psychologist specializing in the study of polymorphic societies—caste systems, gender systems, stratification along lines dictated by heredity, astrology, or other characteristics outside the individual's control. He's published a number of reports lately asserting that people in most societies prior to the Interval Monarchies couldn't act as autonomous agents because of social constraints imposed on them without consent, and I suspect the reason the Scholastium funds his research is because it has diplomatic implications."

I feel Kay shiver slightly through my left arm, which is wrapped around her uppermost shoulders. She leans against me more closely, and I lean against the tree trunk behind me in turn. "Like ice ghoul societies," she murmurs.

"Ice ghouls?" asks Vhora.

"They aren't tech—no, what I mean is that they are still developing technologies. They haven't reached the Acceleration yet. No emotional machines, no virtual or self-replicating toolsets. No Exultants, no gates, no ability to restructure their bodies without ingesting poisonous plant extracts or cutting themselves with metal knives." She shudders slightly. "They're prisoners of their own bodies, they grow old and fall apart, and if one of them loses a limb, they can't replace it." She's very unhappy about something, and for a moment I wonder what the ice ghouls she lived with meant to her, that she has to come here to forget.

"Sounds icky," says Linn. "Anyway, that's what Colonel-Doctor Boateng is interested in. Polities where people have no control over who they are."

"How's the experiment meant to work, then?" I ask, puzzling over it.

"Well, I don't know all the details," Linn temporizes. "But what happens . . . well, if you volunteer, they put you through a battery of tests. You're not supposed to go in if you've got close family attachments and friends, by the way; it's strictly for singletons." Kay's grasp tightens around me for a moment. "Anyway, they back you up and your copy wakes up inside.

"What they've prepared for the experiment is a complete polity—the briefing says there are over a hundred million cubic meters of accommodation space and a complete shortjump network inside. It's not totally uncivilized, like a raw planetary biome or anything. There are a couple of catches, though. There are no free assemblers, you can't simply request any structure you want. If you need food or clothing or tools or whatever, you're supposed to use these special restricted fabricators that'll only give you what you're entitled to within the experiment. They run a money system and provide work, so you have to work and pay for what you consume; it's intended to emulate a pre-Acceleration scarcity economy. Not too scarce, of course—they don't want people starving. The other catch is, well, they assign you a new orthohuman body and a history to play-act with. During the experiment, you're stuck in your assigned role. No netlink, no backups, no editing—if you hurt yourself, you have to wait for your body to repair itself. I mean, they didn't have A-gates back before the Acceleration, did they? Billions of people lived there, it can't be that bad, you just have to be prudent and take care not to mutilate yourself."

"But what's the experiment about?" I repeat. There's something missing; I can't quite put my finger on it . . .

"Well, it's supposed to represent a dark ages society," Linn explains. "We just live in it and follow the rules, and they watch us. Then it ends, and we leave. What more do you need?"

"What are the rules?" asks Kay.

"How should I know?" Linn smiles dreamily as she leans against Vhora, fondling the meso's horn, which is glowing softly pink and pulsing in time to her hand motions. "They're just trying to reinvent a microcosm of the polymorphic society that's ancestral to our own. A lot of our history comes out of the dark ages—it was when the Acceleration took hold—but we know so little about it. Maybe they think trying to understand how dark ages society worked will explain how we got where we are? Or something else. Something to do with the origins of the cognitive dictatorships and the early colonies."