Schild's Ladder

by Greg Egan

  “When they left Earth, they knew they'd be overtaken by newer technologies; they knew they'd be traveling into the future. They knew there'd be established societies along their route. That was why they left. They wanted to witness what humanity would become.”

  “I see.” Yann appeared to be on the verge of raising another objection, but then he let it pass.

  “They had one particular interest, though,” Tchicaya continued. “They told my father that they wanted to know what stage his people were in, in the eternal struggle between women and men. They wanted to hear about the wars, the truces. The victories, the compromises, the setbacks.”

  “Wait. How old is your father now?”

  “About six millennia.”

  “So...” Yann rubbed his neck, perplexed. “Turaev was the very first planet they'd visited? After fourteen thousand years?”

  “No, they'd made planet-fall six times before.”

  Yann spread his arms in surrender. “You've lost me, then.”

  “No one had had the heart to tell them,” Tchicaya explained. “When they first made contact with a modern society, on Crane, it took a while before they were sufficiently at ease to reveal their purpose. But by the time they got around to asking questions, the locals had already gained a clear sense of the kind of preconceptions these travelers had. They'd been in cold storage for millennia, and now they were finally beginning the stage of their voyage that would justify the enormous sacrifices they'd made. Nobody could bring themselves to break the news that the sole surviving remnant of human sexual dimorphism was the retention, in some languages, of different inflections of various parts of speech associated with different proper names—and that expecting these grammatical fossils to be correlated with any aspect of a person's anatomy would be like assuming from similar rules for inanimate objects that a cloud possessed a penis and a table contained a womb.”

  “So they lied to them?” Yann was horrified. “On Crane? And on all the other planets?”

  “It must have seemed like the kindest thing to do,” Tchicaya protested. “And when it started, no one seriously expected them to reach another planet. When they did, though, word had gone ahead of them, so people were much better prepared.”

  “And this happened six times? Even if they were fed the same story on every planet, by the time they'd had a few chances to compare it with reality—”

  Tchicaya shook his head. “They weren't fed the same story on every planet; that would have defeated the whole point. They'd traveled into the future in the hope of being entertained in a very specific way. On Crane, they'd revealed a lot about the kind of histories and practices they expected to encounter on their voyage, and so people played along with their expectations. The locals there told them that all the ‘men’ had been wiped out by a virus shortly after settlement, and made a big song and dance about the struggle to adapt: one faction trying to reinvent the lost sex; another, bravely pursuing monosexuality, finally triumphant. The anachronauts lapped it up, oohing and aahing over all the profound things this told them about gender. They made notes, recorded images, observed a few fake ceremonies and historical re-enactments...then moved on.”

  Yann buried his face in his hands. “This is unforgivable!”

  Tchicaya said, “No one lied to them about anything else. They had some equally bizarre notions about the future of physics, but the people on Crane gave them an honest account of all the latest work.”

  Yann looked up, slightly mollified. “What happened next?”

  “After Crane? It became a kind of competition, to see who could Mead them the best: make up the most outlandish story, and get the anachronauts to swallow it. A plague wasn't really barbaric enough. There had to be war between the sexes. There had to be oppression. There had to be slavery.”

  “Slavery?”

  “Oh yes. And worse. On Krasnov, they said that for five thousand years, men had slaughtered their own firstborn child to gain access to a life-prolonging secretion in mother's milk. The practice had only ended a century before.”

  Yann swayed against the bed. “That's surreal on so many levels, I don't know where to begin.” He regarded Tchicaya forlornly. “This is really what the anachronauts expected? No progress, no happiness, no success, no harmony? Just the worst excesses of their own sordid history, repeated over and over for millennia?”

  Tchicaya said, “On Mäkelä, the people insisted that their planet had been peaceful since settlement. The anachronauts were terribly suspicious, and kept digging for the awful secret that no one dared reveal. Finally, the locals reviewed the transmission from Crane describing the first contact, and they realized what was needed. They explained that their society had been stabilized by the invention of the Sacred Pentad, in which all family units were based around two males, two females, and one neuter.” Tchicaya frowned. “There were rules about the sexual relationships between the members, something about equal numbers of heterosexual and homosexual pairings, but I could never get a clear description of that. But the anachronauts were thrilled by the great ‘cultural richness’ they had finally uncovered. Apparently, their definition of ‘cultural richness’ was the widespread enforcement of any social or sexual mores even more bizarre and arbitrary than the ones they'd left behind.”

  Yann said, “So what happened on Turaev?”

  “The ship had been tracked for centuries, of course, so the mere fact of its arrival was no surprise to anyone. My father had known since early childhood that these strangers would be turning up, somewhere on the planet, at about this time. A variety of different hoaxes had been advocated by different groups, and though none of them had gained planet-wide support, the anachronauts rarely visited more than one place, so it would only require the people in one town to back each other up.

  “My father wasn't prepared at all, though. He hadn't kept up with news of the precise timing of the ship's arrival, and even though he'd been aware that it would happen soon, the chance of planet-fall outside his own town had been too microscopic to worry about. He'd had far more important things on his mind.”

  Yann smiled expectantly, despite himself. “So when the flames died down, and the dust settled, and your father's Mediator dug up the visitors' ancient language from its files...he had to stand there and insist with a straight face that he knew nothing whatsoever about the subject of their inquiries?”

  “Exactly. Neither he nor Lajos had the slightest idea what they were supposed to tell these strangers. If they'd read the reports on the anachronauts, they'd have realized that they could have claimed all manner of elaborate taboos on discussing the subject, but they weren't in a position to know that and invoke some imaginary code of silence. So all they were left with was claiming ignorance: claiming to be both prepubescent, and stupid.” Tchicaya laughed. “After six months of longing for each other? Within days, or even hours, of consumation? I don't know how to translate that into terms you're familiar with—”

  Yann was offended. “I'm not an idiot. I understand how much pride they would have had to swallow. You don't need to spoonfeed me similes.”

  Tchicaya bowed his head in apology, but he held out for precision. “Pride, yes, but it was more than that. Claiming anything but the truth would have felt like they were renouncing each other. Even if they'd known their lines, I'm not sure that they could have gone through with the charade.” He held a fist against his chest. “It hurts, to lie about something like that. Other people might have been swept up in the excitement of the conspiracy. But to Lajos and my father, that was just noise. They were the center of the universe. Nothing else mattered.”

  “So they told them the truth?”

  Tchicaya said, “Yes.”

  “About themselves?”

  He nodded. “And more.”

  “About the whole planet? That this was the custom all over Turaev?”

  “More.”

  Yann emitted an anguished groan. “They told them everything?”

  Tchicaya said, “My
father didn't come right out and state that all their earlier informants had lied to them, but he explained that—apart from a few surviving contemporaries of the travelers themselves—there'd been nothing resembling sexual dimorphism in the descendants of humans, anywhere, for more than nineteen thousand years. Long before any extrasolar world was settled, it had gone the way of war, slavery, parasites, disease, and quantum indecisiveness. And apart from trivial local details, like the exact age of sexual maturity and the latency period between attraction and potency, he and his lover embodied a universal condition: they were both, simply, people. There were no other categories left to which they could belong.”

  Yann pondered this. “So did the intrepid gendographers believe him?”

  Tchicaya held up a hand, gesturing for patience. “They were far too polite to call my father a liar to his face. So they went into town, and spoke to other people.”

  “Who, without exception, gave them the approved version?”

  “Yes.”

  “So they left Turaev none the wiser. With an unlikely tale from two mischievous adolescents to add to their collection of sexual mythology.”

  Tchicaya said, “Perhaps. Except that since Turaev, they haven't made planet-fall anywhere. They've been tracked, the ship's still functioning, and they've had four or five opportunities to enter inhabited systems. But every time, they've flown on by.”

  Yann shivered. “You think it's a ghost ship?”

  Tchicaya said, “No. I think they're in cold sleep, with their bodies frozen, and tiny currents flowing in their brains. Dreaming of all the horrors they'd wished upon us, in the name of some crude, masochistic notion of humanity that must have been dying right in front of them before they'd even left Earth.”

  As Tchicaya boarded the shuttle ahead of Yann, Mariama looked back and flashed him a brief smile. Her meaning was unmistakable, but he pretended not to notice. He didn't mind her knowing what he and Yann had attempted, or even how it had ended, but it drove him to distraction that she could deduce at least half the story just by watching them together.

  He could have instructed his Exoself to embargo whatever small gestures were giving him away. But that was not how he wanted to be: hermetically sealed, blank as a rock. For a moment, Tchicaya contemplated reaching over and putting his arm across Yann's shoulders, just to devalue her powers of observation. On reflection that would have been petty, though, and likely to cause Yann all kinds of confusion.

  Mariama sat beside Tarek. In the unlikely event that the two of them were lovers, Tchicaya would be the last to know. Behind him, the fifth passenger, Branco, strapped himself in place. Tchicaya turned to him and joked, “It doesn't seem right that you're outnumbered. You should at least have brought an observer along.”

  Branco said pleasantly, “Fuck that. The last thing I want to do is start mimicking all your paranoid games.”

  Branco had been part of the original coalition who'd designed and built both the Rindler and the Scribe. Yielders and Preservationists had arrived over the decades, exuding a kind of bureaucratic fog through which he was now forced to march, but as he'd explained to Tchicaya earlier, he'd become inured to the squatters and their demands. The Scribe was still available to its creators, occasionally, and with patience he could still get work done. The factions made a lot of noise, but in the long run, as far as Branco was concerned, they'd be about as significant as the vapid religious cults who'd once squabbled over contested shrines on Earth. “And you sad airheads can't even slaughter each other,” he'd observed gleefully. “How frustrating that must be.”

  As they fell away from the Rindler, Tchicaya barely noticed the weightlessness, or the strange doll's-house/termite-colony view some of the modules offered as they shrank into the distance. The trip hadn't quite become as unremarkable to him as air travel in a planetary atmosphere, but on a planet even repeated flights along the same route were never as unvarying as this.

  Tarek said, “Actually, we're outnumbered, three to two. If you're ‘neutral,’ you're a Yielder. There is no difference.”

  “Oh, here we go!” Branco chuckled and settled back into his couch. “It's a short trip, but please, entertain us.”

  “You're not fooling anyone,” Tarek insisted heatedly.

  “It's not important,” Mariama said. Tchicaya watched her, wondering if she'd make eye contact with Tarek as she spoke. She didn't. “There are observers here for both sides. It doesn't matter how many there are.” Her tone was calm, neither argumentative nor imploring.

  Tarek dropped the subject. Tchicaya was impressed; she'd defused the situation without alienating Tarek, or incurring any debt to him. She hadn't lost her touch, she'd only grown more subtle. When Tchicaya had trailed after her as a tortured, infatuated child, it must have perplexed and frustrated her to find that she couldn't hone her skills on him. Anything above and beyond mere hormonal effects had been superfluous; she might as well have tried to learn martial arts by practicing on a rag doll.

  Branco sighed with disappointment, then closed his eyes and appeared to doze off.

  Most of the Rindler's passengers had watched with a mixture of denial and dismay as Sophus's predictions had been borne out, and all their ingenious models had been dashed to pieces, once again, by the new spectrometer. Branco, however, had embraced the No Rules Theory wholeheartedly, and managed to extract predictions that went far beyond Sophus's gloomy verdict. Just because there were no preexisting correlations between the dynamics on the far side of the border, that didn't mean none could be created. Branco had designed an ingenious experiment that aimed to use the near side of the border as a kind of intermediary, to entangle different regions of the far side with each other. The dynamics revealed would still be a random choice from all the possibilities—or, strictly speaking, the near-side universe would split into decoherent branches, and in each, a different result would be observed—but at least the result would apply across more than a few square Planck lengths.

  As they docked with the Scribe, Yann mused, “I think this is the first time I've come here with any possibility of being disappointed.”

  Tchicaya was taken aback. “You never had your hopes pinned on any of the old models? You never even had a favorite?”

  “There were some esthetically pleasing ones,” Yann conceded. “I certainly would have been happy if they'd survived testing. But I never had a good reason to expect it. Not until now.”

  “That's very touching,” Branco said dryly, “but I see no reason why you should abandon your earlier stance.”

  Tchicaya challenged him, “You have no emotional stake in the outcome at all?”

  Branco regarded him with amusement. “You've been here how long?”

  Tarek went through the tunnel first, then Mariama. Tchicaya followed her. “Do you remember that playground?” he whispered. “With all the pipes?” She glanced back at him, puzzled, and shook her head. Tchicaya felt a stab of disappointment; he'd assumed that the sight would have triggered the same memory in her.

  In the control room, Branco instructed the stylus. With his gravelly voice and deliberate singsong intonation, he succeeded in making every word drip with contempt, like a kind of sardonic poetry. “The phase relationships between the twelve TeV and fifteen TeV beams will be as follows.” They really are making me read this aloud.

  Tchicaya looked out the window, down at the immutable plane of light. He'd had vivid dreams about the border, imagining as he slept that the wall of his cabin was the thing itself. He'd hold his ear against it, listening for sounds from the far side, straining with his whole body, urging the signal across.

  Sometimes, the instant before he woke, he'd see an iridescent film blossoming on the wall, and his heart would race with joy and fear. Did this new infestation mean that he'd been found out? Or that his crime had never really happened?

  Branco looked up and announced with mock astonishment, “Am I finished already? Is that all I have to do?”

  Tarek said, “For now. But I'
m invoking my right to a functional audit.”

  “Hooray,” said Branco. He pushed himself away from the control panel and floated by the window with his hands on his head.

  Tarek took his place, and instructed the stylus to rise from the border. Tchicaya had heard about functional audits, but he'd never witnessed one before. A package of detectors, verified by the faction invoking the audit, was placed under the tip of the stylus, and the particles emitted were scrutinized directly, to be sure that they conformed to the agreed sequence.

  Tchicaya was tempted to say something derisive, but he held his tongue. Whatever made Tarek believe that this was necessary, complaining about the procedure would do nothing to lessen his suspicions.

  He used the handholds beneath the windows to drag himself closer to Mariama. “Where have you been hiding? I haven't seen you for weeks.”

  “I have a lot of meetings.”

  “I go to meetings, too.”

  “Not these ones,” she said.

  She didn't need to spell it out. She'd come to the Rindler hoping to work with Tarek on Planck worm design, and apparently the notion still wasn't dead.

  The novo-vacuum was already the largest object in the galaxy, and it was growing so rapidly that its surface area would increase almost forty-fold while it was encircled at the speed of light. Even if the Preservationists discovered a potential method for dealing with it, there was no prospect whatsoever of surrounding the entire thing with conventional machinery to administer the cure. The only practical tool would be a self-replicating pattern embedded at the level of quantum graphs, able to “eat” novo-vacuum and excrete something more benign.

  To supporters of the idea, these hypothetical Planck worms would do no more than reverse the disaster of Mimosa. To Tchicaya, the symmetry was false. The places lost to Mimosa—ordinary planets, unique as they were—had already been thoroughly understood. Learning just enough about the novo-vacuum to infect it with a kind of fungal rot struck him as a corruption of every impulse that made intelligence worthwhile. He had enough trouble forgiving that kind of cowardice in a child.