Permutation City

by Greg Egan

  She’d persuaded him to postpone baling out until he’d considered the alternatives. She hadn’t had to argue hard; the mere fact of her presence had already improved his outlook immeasurably. Thousands of Copies, she’d said, survived with slowdown factors of thirty, sixty, or worse – playing no part in human society, earning no money but the passive income from their trust funds, living at their own speed, defining their worth on their own terms. He had nothing to lose by trying it himself.

  And if he couldn’t accept that kind of separatist existence? He always had the choice of suspending himself, in the hope that the economics of ontology would eventually shift in his favor – albeit at the risk of waking to find that he’d matched speeds with a world far stranger, far harder to relate to, than the present in fast motion.

  For someone whose fondest hope had been to wake in a robot body and carry on living as if nothing had changed, the slums were a shock. Kate had shown him around the Slow Clubs – the meeting places for Copies willing to synch to the rate of the slowest person present. Not a billionaire in sight. At the Cabaret Andalou, the musicians presented as living saxophones and guitars, songs were visible, tangible, psychotropic radiation blasting from the mouths of the singers – and on a good night, a strong enough sense of camaraderie, telepathy, synergy, could by the mutual consent of the crowd take over, melting away (for a moment) all personal barriers, mental and mock-physical, reconstructing audience and performers into a single organism: one hundred eyes, two hundred limbs, one giant neural net resonating with the memories, perceptions and emotions of all the people it had been.

  Kate had shown him some of the environments she’d bought – and some she’d built herself – where she lived and worked in solitude. An overgrown, oversized, small-town back garden in early summer, an enhanced and modified childhood memory, where she carved solid sculptures out of nothing but the ten-to-the-ten-thousandth possibilities of color, texture and form. A bleak gray stretch of shoreline under eternally threatening clouds, the sky dark oil on canvas, a painting come to life where she went to calm herself when she chose not to make the conscious decision to be calm.

  She’d helped him redesign his apartment, transforming it from a photorealist concrete box into a system of perceptions which could be as stable, or responsive, as he wished. Once, before sleep, he’d wrapped the structure around himself like a sleeping bag, shrinking and softening it until the kitchen cradled his head, and the other rooms draped his body. He’d changed the topology so that every window looked in through another window, every wall abutted another wall; the whole thing closed in on itself in every direction, finite but borderless, universe-as-womb.

  And Kate had introduced him to Daniel Lebesgue’s interactive philosophical plays: The Beholder, The Sane Man (his adaptation of Pirandello’s Enrico IV), and of course, Solipsist Nation. Hawthorne had taken the role of John Beckett, a reluctant Copy obsessed with keeping track of the outside world – who ends up literally becoming an entire society and culture himself. The play’s software hadn’t enacted that fate upon Hawthorne – intended for visitors and Copies alike, it worked on the level of perceptions and metaphors, not neural reconstruction. Lebesgue’s ideas were mesmerizing, but imprecise, and even he had never tried to carry them through – so far as anyone knew. He’d vanished from sight in 2036; becoming a recluse, baling out, or suspending himself, nobody could say. His disciples wrote manifestos, and prescriptions for virtual utopias; in the wider vernacular, though, to be “Solipsist Nation” simply meant to have ceased deferring to the outside world.

  Three subjective weeks – almost four real-time years – after his resurrection, Hawthorne had stepped off the merry-go-round long enough to catch up with the news from outside. There’d been nothing especially dramatic or unexpected in the summaries – no shocking political upheavals, no stunning technological breakthroughs, no more nor less civil war or famine than in the past. The BBC’s headlines of the day: Five hundred people had died in storms in south-east England. The European Federation had cut its intake of environmental refugees by forty percent. Korean investors had gone ahead with a threatened embargo on US government bonds, as part of a trade war over biotechnology tariffs, and utilities had begun disconnecting power, water and communications services from federal buildings. Up-to-the-minute details notwithstanding, it had all seemed as familiar as some brand-name breakfast food: the same texture, the same taste, as he remembered from four, from eight, years before. With his eyes locked on the terminal in front of him, the oddly soothing generic images drawing him in, the three hallucinatory weeks of dancing saxophones and habitable paintings had receded into insignificance, as if they’d been nothing but a vivid dream. Or at least, something on another channel, with no risk of being mistaken for news.

  Kate had said, “You know, you can sit here forever, watch this forever, if that’s what you want. There are Copies – we call them Witnesses – who refine themselves into … systems … which do nothing but monitor the news, as thoroughly as their slowdown allows. No bodies, no fatigue, no distractions. Pure observers, watching history unfold.”

  “That’s not what I want.”

  He hadn’t taken his eyes off the screen, though. Inexplicably, he’d started to cry, softly, grieving for something that he couldn’t name. Not the world defined by the news systems; he’d never inhabited that place. Not the people who’d sent him their recorded farewells; they’d been useful at the time, but they meant nothing to him anymore.

  “But?”

  “But outside is still what’s real to me – even if I can’t be a part of it. Flesh and blood. Solid ground. Real sunlight. It’s still the only world that matters, in the end. I can’t pretend I don’t know that. Everything in here is just beautiful, inconsequential fiction.” Including you. Including me.

  Kate had said, “You can change that.”

  “Change what? Virtual Reality is Virtual Reality. I can’t transform it into something else.”

  “You can change your perspective. Change your attitudes. Stop viewing your experiences here as less than real.”

  “That’s easier said than done.”

  “But it isn’t.”

  She’d summoned up a control panel, shown him the software he could use: a program which would analyze his model-of-a-brain, identify his qualms and misgivings about turning his back on the world – and remove them.

  “A do-it-yourself lobotomy.”

  “Hardly. There’s no ‘physical’ excision. The program carries out trial-and-error adjustment of synaptic weights, until it finds the minimum possible alteration which achieves the desired goal. A few billion short-lived stripped-down versions of your brain will be tested and discarded along the way, but don’t let that bother you.”

  “You’ve run this on yourself?”

  She’d laughed. “Yes. Out of curiosity. But it found nothing to change in me. I’d already made up my mind. Even on the outside, I knew this was what I wanted.”

  “So … I press a button and there’s someone new sitting here? One instant synthetic satisfied customer? I annihilate myself, just like that?”

  “You’re the one who jumped off a cliff.”

  “No. I’m the one who didn’t.”

  “You won’t ‘annihilate yourself.’ You’ll only change as much as you have to. And you’ll still call yourself David Hawthorne. What more can you ask for? What more have you ever done?”

  They’d talked it through for hours, debating the fine philosophical and moral points; the difference between “naturally” accepting his situation, and imposing acceptance upon himself. In the end, though, when he’d made the decision, it had seemed like just another part of the dream, just another inconsequential fiction. In that sense, the old David Hawthorne had been true to his beliefs – even as he rewired them out of existence.

  Kate had been wrong about one thing. Despite the perfect continuity of his memories, he’d felt compelled to mark the transition by choosing a new name, plucking the wh
imsical monosyllable out of thin air.

  The “minimum possible alteration”? Perhaps if he had ended up less radically Solipsist Nation, far more of his personality would have to have been distorted for him to have been convinced at all. A few bold necessary cuts had squared the circle, instead of a thousand finicky mutilations.

  That first change, though, had cleared the way for many more, a long series of self-directed mutations. Peer (by choice) had no patience with nostalgia or sentimentality; if any part of his personality offended him, he struck it out. Some traits had (most likely) vanished forever: a horde of petty jealousies, vanities, misgivings, and pointless obsessions; a tendency to irrational depression and guilt. Others came and went. Peer had acquired, removed, and restored, a variety of talents, mood predispositions, and drives; cravings for knowledge, art, and physical experience. In a few subjective days, he could change from an ascetic bodiless student of Sumerian archaeology, to a hedonistic gastronome delighting in nothing more than the preparation and consumption of lavishly simulated feasts, to a disciplined practitioner of Shotokan karate.

  A core remained; certain values, certain emotional responses, certain esthetic sensibilities had survived these transitions unscathed.

  As had the will to survive itself.

  Peer had once asked himself: Was that kernel of invariants – and the more-or-less unbroken thread of memory – enough? Had David Hawthorne, by another name, achieved the immortality he’d paid for? Or had he died somewhere along the way?

  There was no answer. The most that could be said, at any moment, was that someone existed who knew – or believed – that they’d once been David Hawthorne.

  And so Peer had made the conscious decision to let that be enough.

  Chapter 12

  (Rip, tie, cut toy man)

  June 2045

  Paul switched on the terminal and made contact with his old organic self. The djinn looked tired and frayed; all the begging and bribery required to set up the latest stage of the experiment must have taken its toll. Paul felt more alive than he’d ever felt, in any incarnation; his stomach was knotted with something like fear, but the electric tingling of his skin felt more like the anticipation of triumph. His body was about to be mutilated, carved up beyond recognition – and yet he knew he would survive, suffer no harm, feel no pain.

  Squeak. “Experiment three, trial zero. Baseline data. All computations performed by processor cluster number four six two, Hitachi Supercomputer Facility, Tokyo.”

  “One. Two. Three.” It was nice to be told where he was, at last; Paul had never visited Japan, before. “Four. Five. Six.” And on his own terms, he still hadn’t. The view out the window was Sydney, not Tokyo; why defer to the external geography, when it made no difference at all? “Seven. Eight. Nine. Ten.”

  Squeak. “Trial number one. Model partitioned into five hundred sections, run on five hundred processor clusters, distributed globally.”

  Paul counted. Five hundred clusters. Five only for the crudely modeled external world; all the rest were allocated to his body – and most to the brain. He lifted his hand to his eyes – and the information flow that granted him motor control and sight traversed tens of thousands of kilometers of optical cable. There was no (perceptible) delay; each part of him simply hibernated when necessary, waiting for the requisite feedback from around the world.

  It was, of course, pure lunacy, computationally and economically; Paul guessed that he was costing at least a hundred times as much as usual – not quite five hundred, since each cluster’s capacity was only being partly used – and his slowdown factor had probably risen from seventeen to as much as fifty. Once it had been hoped that devoting hundreds of computers to each Copy might improve the slowdown problem, not worsen it – but the bottlenecks in shifting data between processor clusters kept even the richest Copies from reducing the factor below seventeen. It didn’t matter how many supercomputers you owned, because splitting yourself between them wasted more time on communications than was saved by the additional computing power.

  Squeak. “Trial number two. One thousand sections, one thousand clusters.”

  Brain the size of a planet – and here I am, counting to ten. Paul recalled the perennial – naïve and paranoid – fear that all the networked computers of the world might one day spontaneously give birth to a global hypermind – but he was, almost certainly, the first planet-sized intelligence on Earth. He didn’t feel much like a digital Gaia, though. He felt exactly like an ordinary human being sitting in a room a few meters wide.

  Squeak. “Trial number three. Model partitioned into fifty sections and twenty time sets, implemented on one thousand clusters.”

  “One. Two. Three.” Paul struggled to imagine the outside world on his own terms, but it was almost impossible. Not only was he scattered across the globe, but widely separated machines were simultaneously computing different moments of his subjective time frame. Was the distance from Tokyo to New York now the length of his corpus callosum? Had the world shrunk to the size of his skull – and vanished from time altogether, except for the fifty computers which contributed at any one time to what he called “the present”?

  Maybe not – although in the eyes of some hypothetical space traveler, the whole planet was virtually frozen in time, and flat as a pancake. Relativity declared that this point of view was perfectly valid – but Paul’s was not. Relativity permitted continuous deformation, but no cutting and pasting. Why not? Because it had to allow for cause and effect. Influences had to be localized, traveling from point to point at a finite velocity; chop up space-time and rearrange it, and the causal structure would fall apart.

  What if you were an observer, though, who had no causal structure? A self-aware pattern appearing by chance in the random twitches of a noise machine, your time coordinate dancing back and forth through causally respectable “real time”? Why should you be declared a second-class being, with no right to see the universe your way? Ultimately, what difference was there between so-called cause and effect, and any other internally consistent pattern?

  Squeak. “Trial number four. Model partitioned into fifty sections and twenty time sets; sections and states randomly allocated to one thousand clusters.”

  “One. Two. Three.”

  Paul stopped counting, stretched his arms wide, stood up slowly. He wheeled around once, to examine the room, checking that it was still intact, still complete. Then he whispered, “This is dust. All dust. This room, this moment, is scattered across the planet, scattered across five hundred seconds or more – but it still holds itself together. Don’t you see what that means?”

  The djinn reappeared, but Paul didn’t give him a chance to speak. The words flowed out of him, unstoppable. He understood.

  “Imagine … a universe entirely without structure, without shape, without connections. A cloud of microscopic events, like fragments of space-time … except that there is no space or time. What characterizes one point in space, for one instant? Just the values of the fundamental particle fields, just a handful of numbers. Now, take away all notions of position, arrangement, order, and what’s left? A cloud of random numbers.

  “That’s it. That’s all there is. The cosmos has no shape at all – no such thing as time or distance, no physical laws, no cause and effect.

  “But … if the pattern that is me could pick itself out from all the other events taking place on this planet … why shouldn’t the pattern we think of as ‘the universe’ assemble itself, find itself, in exactly the same way? If I can piece together my own coherent space and time from data scattered so widely that it might as well be part of some giant cloud of random numbers … then what makes you think that you’re not doing the very same thing?”

  The djinn’s expression hovered between alarm and irritation.

  Squeak. “Paul … what’s the point of all this? ‘Space-time is a construct; the universe is really nothing but a sea of disconnected events …’ Assertions like that are meaningless. You ca
n believe it if you want to … but what difference would it make?”

  “What difference? We perceive – we inhabit – one arrangement of the set of events. But why should that arrangement be unique? There’s no reason to believe that the pattern we’ve found is the only coherent way of ordering the dust. There must be billions of other universes coexisting with us, made of the very same stuff – just differently arranged. If I can perceive events thousands of kilometers and hundreds of seconds apart to be side-by-side and simultaneous, there could be worlds, and creatures, built up from what we’d think of as points in space-time scattered all over the galaxy, all over the universe. We’re one possible solution to a giant cosmic anagram … but it would be ludicrous to believe that we’re the only one.”

  Squeak. Durham snorted. “A cosmic anagram? So where are all the left-over letters? If any of this were true – and the primordial alphabet soup really is random – don’t you think it’s highly unlikely that we could structure the whole thing?”

  Paul thought about it. “We haven’t structured the whole thing. The universe is random, at the quantum level. Macroscopically, the pattern seems to be perfect; microscopically, it decays into uncertainty. We’ve swept the residue of randomness down to the lowest level.”

  Squeak. The djinn strived visibly for patience. “Paul … none of this could ever be tested. How would anyone ever observe a planet whose constituent parts were scattered across the universe? Let alone communicate with its hypothetical inhabitants. What you’re saying might have a certain – purely mathematical – validity: grind the universe into fine enough dust, and maybe it could be rearranged in other ways that make as much sense as the original. If those rearranged worlds are inaccessible, though, it’s all angels on the heads of pins.”

  “How can you say that? I’ve been rearranged! I’ve visited another world!”