Permutation City

by Greg Egan

  Maria was already confused. From the hurried reading she’d done in the past few days, she knew that the Lambertians only modified an established theory when a new phenomenon was discovered which the theory failed to explain. Repetto must have noticed her expression, because he paused expectantly.

  She said, “Autoverse atoms are indivisible. There are no components you can separate out, no smaller stable entities. Smash them together at any energy you like, and all they’ll do is bounce – and the Lambertians are in no position to smash them together at any energy at all. So … surely there’s nothing in their experience that the current theory can’t account for perfectly.”

  “Nothing in their immediate environment, certainly. But the problem is cosmology. They’ve been refining the models of the history of their star system, and now they’re looking for an explanation for the composition of the primordial cloud.”

  “They accepted the thirty-two atoms and their properties as given – but they can’t bring themselves to do the same with the arbitrary amounts of each one in the cloud?”

  “That’s right. It’s difficult to translate the motivation exactly, but they have a very precise esthetic which dictates what they’ll accept as a theory – and it’s almost physically impossible for them to contradict it. If they try to dance a theory which fails to resonate with the neural system which assesses its simplicity, the dance falls apart.” He thought for a second, then pointed to the screen behind him; a swarm of Lambertians appeared. “Here’s an example – going back awhile. This is a team of astronomers – all fully aware of the motions of the planets in the sky, relative to the sun – testing out a theory which attempts to explain those observations by assuming that Planet Lambert is fixed, and everything else orbits around it.”

  Maria watched the creatures intently. She would have been hard pressed to identify the rhythms in their elaborate weaving motions – but when the swarm began to drift apart, the collapse of order was obvious.

  “Now here’s the heliocentric version, from a few years later.”

  The dance, again, was too complex to analyze – although it did seem to be more harmonious – and after a while, almost hypnotic. The black specks shifting back and forth against the white sky left trails on her retinas. Below, the ubiquitous grassland seemed an odd setting for astronomical theorizing. The Lambertians apparently accepted their condition – in which herding mites represented the greatest control they exerted over nature – as if it constituted as much of a utopia as the Elysians’ total freedom. They still faced predators. Many still died young from disease. Food was always plentiful, though; they’d modeled their own population cycles, and learned to damp the oscillations, at a very early stage. And, nature lovers or not, there’d been no “ideological” struggles over “birth control”; once the population model had spread, the same remedies had been adopted by communities right across the planet. Lambertian cultural diversity was limited; far more behavior was genetically determined than was the case in humans – the young being born self-sufficient, with far less neural plasticity than a human infant – and there was relatively little variation in the relevant genes.

  The heliocentric theory was acceptable; the dance remained coherent. Repetto replayed the scene, with a “translation” in a small window, showing the positions of the planets represented at each moment. Maria still couldn’t decipher the correspondence – the Lambertians certainly weren’t flying around in simple mimicry of the hypothetical orbits – but the synchronized rhythms of planets and insect-astronomers seemed to mesh somewhere in her visual cortex, firing some pattern detector which didn’t know quite what to make of the strange resonance.

  She said, “So Ptolemy was simply bad grammar – obvious nonsense. Doubleplus ungood. And they reached Copernicus a few years later? That’s impressive. How long did they take to get to Kepler … to Newton?”

  Zemansky said smoothly, “That was Newton. The theory of gravity – and the laws of motion – were all part of the model they were dancing; the Lambertians could never have expressed the shapes of the orbits without including a reason for them.”

  Maria felt the hairs rise on the back of her neck.

  “If that was Newton … what came before?”

  “Nothing. That was the first successful astronomical model – the culmination of about a decade of trial and error by teams all over the planet.”

  “But they must have had something. Primitive myths. Stacks of turtles. Sun gods in chariots.”

  Zemansky laughed. “No turtles or chariots, obviously – but no: no naïve cosmologies. Their earliest language grew out of the things they could easily observe and model – ecological relationships, population dynamics. When cosmology was beyond their grasp, they didn’t even try to tackle it; it was a non-subject.”

  “No creation myths?”

  “No. To the Lambertians, believing any kind of ‘myth’ – any kind of vague, untestable pseudo-explanation – would have been like … suffering hallucinations, seeing mirages, hearing voices. It would have rendered them completely dysfunctional.”

  Maria cleared her throat. “Then I wonder how they’ll react to us.”

  Durham said, “Right now, creators are a non-subject. The Lambertians have no need of that hypothesis. They understand evolution: mutation, natural selection – they’ve even postulated some kind of macromolecular gene. But the origin of life remains an open question, too difficult to tackle, and it would probably be centuries before they realized that their ultimate ancestor was seeded ‘by hand’ … if in fact there’s any evidence to show that – any logical reason why A. hydrophila couldn’t have arisen in some imaginary pre-biotic history.

  “But it won’t come to that; after a few more decades banging their heads against the problem of the primordial cloud, I think they’ll guess what’s going on. An idea whose time has come can sweep across the planet in a matter of months, however exotic it might be; these creatures are not traditionalists. And once the theory that their world was made arises in the proper scientific context, it’s not going to drive them mad. All Alissa was saying was that the sort of primitive superstitions which early humans believed in wouldn’t have made sense to the early Lambertians.”

  Maria said, “So … we’ll wait until ‘creators’ are no longer a non-subject before we barge in and announce that that’s exactly what we are?”

  Durham replied, “Absolutely. We have permission to make contact once the Lambertians have independently postulated our existence – and no sooner.” He laughed, and added, with evident satisfaction, “Which we achieved by asking for much more.”

  Maria still felt uneasy – but she didn’t want to hold up proceedings while she grappled with the subtleties of Lambertian culture.

  She said, “All right. Cosmology is the trigger, but they’re looking for a deeper explanation for their chemistry. Are they having any luck?”

  Repetto brought back the map of Planet Lambert; the markers showing the locations of the teams of theorists were replaced by small bar charts in the same positions. “These are the dance times sustained for various subatomic models which have been explored over the past five years. A few theories are showing some promise, improving slightly with each refinement; other groups are getting fairly random results. Nobody’s come up with anything they’d be capable of communicating over any distance; these dances are too short-lived to be remembered by teams of messengers.”

  Maria felt her skin crawl, again. False messages die, en route. There was something chilling about all this efficiency, this ruthless pursuit of the truth. Or maybe it was just a matter of injured pride: treating some of humanity’s most hard-won intellectual achievements as virtually self-evident wasn’t the most endearing trait an alien species could possess.

  She said, “So … no team is on the verge of discovering the truth?”

  Repetto shook his head. “Not yet. But the Autoverse rules are the simplest explanation for the thirty-two atoms, by almost any criterion.” />
  “Simplest to us. There’s nothing in the Lambertians’ environment to make them think in terms of cellular automata.”

  Zemansky said, “There was nothing in their environment to make them think in terms of atoms.”

  “Well, no, but the ancient Greeks thought of atoms – but they didn’t come up with quantum mechanics.” Maria couldn’t imagine a pre-industrial human inventing the cellular automaton – even as a mathematical abstraction – let alone going on to hypothesize that the universe itself might be one. Clockwork cosmologies had come after physical clocks; computer cosmologies had come after physical computers.

  Human history, though, clearly wasn’t much of a guide to Lambertian science. They already had their Newtonian – “clockwork” – planetary model. They didn’t need artifacts to point the way.

  She said, “This ‘esthetic’ which governs the acceptability of theories – have you been able to map the neural structures involved? Can you reproduce the criteria?”

  Repetto said, “Yes. And I think I know what you’re going to ask next.”

  “You’ve devised your own versions of possible Lambertian cellular automaton theories? And you’ve tested them against the Lambertian esthetic?”

  He inclined his head modestly. “Yes. We don’t model whole brains, of course – that would be grossly unethical – but we can run simulations of trial dances with non-conscious Lambertian neural models.”

  Modeling Lambertians modeling the Autoverse…

  “So how did it go?”

  Repetto was hesitant. “The results so far are inconclusive. None of the theories I’ve constructed have worked – but it’s a difficult business. It’s hard to know whether or not I’m really stating the hypothesis in the way the Lambertians would – or whether I’ve really captured all the subtleties of the relevant behavior in a non-conscious model.”

  “But it doesn’t look promising?”

  “It’s inconclusive.”

  Maria thought it over. “The Autoverse rules, alone, won’t explain the abundances of the elements – which is the main problem the Lambertians are trying to solve. So what happens if they miss the whole idea of a cellular automaton, and come up with a completely different theory: something utterly misguided … which fits all the data nonetheless? I know, they’ve grasped everything else about their world far more smoothly than humans ever did, but that doesn’t make them perfect. And if they have no tradition of giving up on difficult questions by invoking the hand of a creator, they might cobble together something which explains both the primordial cloud, and the chemical properties of the elements – without coming anywhere near the truth. That’s not impossible, is it?”

  There was an awkward silence. Maria wondered if she’d committed some terrible faux pas by suggesting that the criteria for contact might never be met … but she could hardly be telling these people anything they hadn’t already considered.

  Then Durham said simply, “No, it’s not impossible. So we’ll just have to wait and see where the Lambertians’ own logic takes them.”

  Chapter 27

  (Rut City)

  Peer felt the change begin, and switched off the lathe. He looked around the workshop helplessly, his eyes alighting on object after object which he couldn’t imagine living without: the belt sander, the rack full of cutting tools for the lathe, cans of oil, tins of varnish. The pile of freshly cut timber itself. Abandoning these things – or worse, abandoning his love of them – seemed like the definition of extinction.

  Then he began to perceive the situation differently. He felt himself step back from his life as a carpenter into the larger scheme of things – or non-scheme: the random stuttering from pretext to pretext which granted his existence its various meanings. His sense of loss became impossible to sustain; his enthusiasm for everything to which he’d been devoted for the past seventy-six years evaporated like a dream. He was not repelled, or bewildered, by the phase he was leaving behind – but he had no desire to extend or repeat it.

  His tools, his clothes, the workshop itself, all melted away, leaving behind a featureless gray plain, stretching to infinity beneath a dazzling blue sky, sunless but radiant. He waited calmly to discover his new vocation – remembering the last transition, and thinking: these brief moments between are a life in themselves. He imagined picking up the same train of thought and advancing it, slightly, the next time.

  Then the empty ground grew a vast room around him, stretching in all directions for hundreds of meters, full of row after row of yellow wooden specimen drawers. A high ceiling with dusty skylights came together above him, completing the scene. He blinked in the gloom. He was wearing heavy black trousers and a waistcoat over a stiff white shirt. His exoself, having chosen an obsession which would have been meaningless in a world of advanced computers, had dressed him for the part of a Victorian naturalist.

  The drawers, he knew, were full of beetles. Hundreds of thousands of beetles. He was free, now, to do nothing with his time but study them, sketch them, annotate them, classify them: specimen by specimen, species by species, decade after decade. The prospect was so blissful that he almost keeled over with joy.

  As he approached the nearest set of drawers – where a blank legal pad and pencil were already waiting for him – he hesitated, and tried to make sense of his feelings. He knew why he was happy, here: his exoself had rewired his brain, yet again, as he’d programmed it to do. What more sense did he require?

  He looked around the musty room, trying to pin down the source of his dissatisfaction. Everything was perfect, here and now – but his past was still with him: the gray plain of transition, his decades at the lathe, the times he’d spent with Kate, his previous obsessions. The long dead David Hawthorne, invincible, clinging to a rock face. None of it bore the slightest connection to his present interests, his present surroundings – but the details still hovered at the edge of his thoughts: superfluous, anachronistic distractions.

  He was dressed for a role – so why not complete the illusion? He’d tinkered with false memories before. Why not construct a virtual past which “explained” his situation, and his enthusiasm for the task ahead, in terms which befitted the environment? Why not create a person with no memory of Peer, who could truly lose himself in the delights of being unleashed on this priceless collection?

  He opened a window to his exoself, and together they began to invent the biography of an entomologist.

  #

  Peer stared blankly at the flickering electric lamp in the corner of the room, then marched over to it and read the scrawled note on the table beneath.

  TALK TO ME. SOMETHING IS WRONG.

  He hesitated, then created a door beside the lamp. Kate stepped through. She was ashen.

  She said, “I spend half my life trying to reach you. When is it going to stop?” Her tone was flat, as if she wanted to be angry but didn’t have the strength. Peer raised a hand to her cheek; she pushed it away.

  He said, “What’s the problem?”

  “The problem? You’ve been missing for four weeks.”

  Four weeks? Peer almost laughed, but she looked so shaken that he stopped himself. He said, “You know I get caught up in what I’m doing. It’s important to me. But I’m sorry if you were worried—”

  She brushed his words aside. “You were missing. I didn’t say: you didn’t answer my call. The environment we’re standing in – and its owner – did not exist.”

  “Why do you think that?”

  “The communications software announced that there was no process accepting data addressed to your personal node. The system lost you.”

  Peer was surprised. He hadn’t trusted Malcolm Carter to start with, but after all this time it seemed unlikely that there were major problems with the infrastructure he’d woven into the City for them.

  He said, “Lost track of me, maybe. For how long?”

  “Twenty-nine days.”

  “Has this ever happened before?”

  Kate laughed
bitterly. “No. What – do you think I would have kept it to myself? I have never come across a basic software failure of any kind, until now. And there are automatic logs which confirm that. This is the first time.”

  Peer scratched his neck beneath the starched collar. The interruption had left him disoriented; he couldn’t remember what he’d been doing when the flashing lamp had caught his attention. His memory needed maintenance. He said, “It’s worrying – but I don’t see what we can do, except run some diagnostics, try to pinpoint the problem.”

  “I ran diagnostics while the problem was happening.”

  “And—?”

  “There was certainly nothing wrong with the communications software. But none of the systems involved with running you were visible to the diagnostics.”

  “That’s impossible.”

  “Did you suspend yourself?”

  “Of course not. And that wouldn’t explain anything; even if I had, the systems responsible for me would still have been active.”

  “So what have you been doing?”

  Peer looked around the room, back to where he’d been standing. There was a specimen drawer on one of the desks, and a thick legal pad beside it. He walked up to the desk. Kate followed.

  He said, “Drawing beetles, apparently.” Perhaps a hundred pages of the pad had been used and flipped over. An unfinished sketch of one of the specimens was showing. Peer was certain that he’d never seen it before.

  Kate picked up the pad and stared at the drawing, then flipped back through the previous pages.

  She said, “Why the pseudonym? Aren’t the clothes affectation enough?”

  “What pseudonym?”

  She held the pad in front of him, and pointed to a signature. “Sir William Baxter, FRS.”