Schild’s Ladder

people here that he knew well, but there were hundreds of complete strangers, too; the ranks of the Preservationists had been swelled by new arrivals.

The audience was completely silent. There was an expression of stony resentment on some faces, an unambiguously hostile gaze, but most people just looked tired and frayed, as if the thing they hated most was not the presence of Yielders bearing unpalatable revelations, but the sheer burden of having to make an invidious choice. Tchicaya could relate to that; part of him longed for nothing more than a turn of events that would render all further effort irrelevant, one way or another, so he could curl up and sleep for a week.

Rasmah began. “You’ve seen the results of our recent experiments, and I’m going to assume that you’ve replicated them successfully. Perhaps someone will correct me if that’s wrong, and the raw data is in dispute.”

She paused. Sophus called out, “That’s not in dispute.” Tchicaya felt a small weight lifting; if there’d been a technical hitch, or some elaborate bluff in which the Preservationists claimed that they’d seen nothing, the whole discussion would have bogged down in recriminations immediately.

Rasmah said, “Good. You’ve also seen Umrao’s simulations, and I hope you’ve performed some of your own. We could sit here for a week debating whether or not the structures we’ve called vendeks deserve to be described as living creatures, but it’s plain that a community of them?—?or a mixture, if you prefer a more neutral term?—?forms a completely different backdrop than the vacuum we’re familiar with, or anything else most of us imagined we’d find behind the border when we made our way here.

“We’ve all pinned states with exotic dynamic laws to the border. We’ve seen tens of thousands of samples from the whole vast catalog of vacuum-based physics. But the far side’s natural state, the closest it can come to emptiness and homogeneity, has access to all of those possibilities at once.

“I came here expecting to see physics written in a different alphabet, obeying a different grammar, but conforming to the same kind of simple rules as our own. It was Sophus who first realized how myopic that expectation was. Our vacuum isn’t just devoid of matter; our universe isn’t simply sparse, in a material sense. What lies behind the border is neither physics in a different language, nor an amorphous, random Babel of every possibility jumbled together. It’s a synthesis: a world painted in hues so rich that everything we’ve previously imagined as a possible universe begins to seem like a canvas filled from edge to edge with a single primary color.

“We’ve seen hints, now, that there might be organisms far more sophisticated than the vendeks, just behind the border. There’s probably nothing I can say that will influence your interpretation of the evidence. I’m not certain what it means, myself. It could be anything: sentient creatures longing for contact; a mating song between animals; an inanimate system constrained by far-side physics to lie in a state more ordered than our instincts deem likely. I don’t know the answer, nor do any of you.

“Maybe there is no far-side life worth speaking of. Maybe there are just different pools of vendeks, all the way down. We can’t tell yet. But imagine for a moment that the signal we’re seeing comes from a creature even as complex as an insect. If life of that sophistication can arise in just six hundred years, then the far side must be so amenable to structure, and order, and complexity that it’s almost inconceivable that we’d be unable either to adapt to it, or to render parts of it hospitable.

“Suppose we were handed a galaxy’s worth of planets, all so near to Earthlike that we could either terraform them easily, or tweak a few genes of our own in order to flourish on them. What’s more, suppose they came clustered together, so close that the time it took to travel between them was negligible: days or weeks, instead of decades or centuries. If we migrated to these worlds, it would mean an end to our fragmentation, an end to the rule that says: yes, you can see how other cultures live, but the price you pay will be alienation from your own.

“On top of this, imagine that interspersed among these Earthlike worlds was another galaxy’s worth of planets, all dense with a riotous variety of alien life. On top of that, imagine that these worlds were immersed in a new kind of physics, so rich and strange that it would trigger a renaissance in science that would last ten thousand years, transform technology, reinvigorate art.

“Is that what the far side really is offering us? I don’t know, and neither do you. Maybe there are some of you for whom it makes no difference: whatever lies behind the border, it can’t be worth the price of even one more planet lost, one more people scattered. But I hope that many of you are willing to pause and say: Mimosa has brought tragedy and turmoil, and that has to be stopped, but not at any cost. If there is a world behind the border that could bring new mysteries, new knowledge, and ultimately a new sense of belonging to billions of people?—?a place that could mean as much to our descendants as our home worlds mean to us?—?then it can’t be unimaginable that the balance could ever tip in its favor.

“People left families and nations behind them on Earth. They’d swum in rivers and walked on mountains that they would never see again. Were they all traitors, and fools? They didn’t destroy the Earth in their wake, they didn’t force the same sacrifice on anyone else, but they did put an end to the world as it had been, when humanity had been connected?—?when the speed of light was a phrase that meant instant contact, instant collisions of cultures and values, not a measure of your loss if you tried to achieve those things.

“I don’t know what lies behind the border, but possibilities that seemed like castles in the air a year ago are now a thousand times less fanciful. Everything I’ve talked about might yet turn out to be a mirage, but if so, it’s a mirage that we’ve all seen with our own two eyes now, hovering uncertainly in the heat haze. A few more steps toward it will tell us, once and for all, whether or not it’s real.

“That’s why I’m asking for this moratorium. Whether you recoil from the vision I’ve painted, or merely doubt its solidity, don’t make a decision in ignorance. Give us one more year, work beside us, help us find the answers?—? and then make your choice. Thank you.”

Rasmah took half a step back from the podium. Someone in the audience coughed. There was no polite applause, but no jeering either. Tchicaya didn’t know how to read the indifferent silence, but Rasmah had been fishing for converts rather than searching for a compromise, and if anyone had been swayed by her message that would probably not be a response they’d wish to broadcast.

Tarek said, “We’ll take questions when Tchicaya has spoken.”

Rasmah nodded and walked away from the podium. As she passed Tchicaya, she smiled encouragingly and touched his arm. He was beginning to wish he’d gone first, and not just because she was a hard act to follow. Before a gathering of Yielders, a speech like the one she’d just delivered would have fired him up, filling him with confidence. Watching it received with no visible effect by the people who counted was a sobering experience.

Tchicaya reached the podium and looked up at the crowd, without fixing his eyes on any one face. Mariama would be here, somewhere, but he counted himself lucky that he hadn’t spotted her, that her certain presence remained an abstraction.

“There is a chance,” he said, “that there is sentient life behind the border. We have no proof of this. We lack the depth of understanding we’d need even to begin to quantify the odds. But we do know that complex processes that would have been inconceivable in a vacuum?—?or in the kind of hot plasma present in our own universe, six hundred years after its birth?—?are taking place right now on the far side. Whether or not you count the vendeks as living creatures, they reveal that the basic structure of this region is nothing at all like empty space.

“None of us arrived here armed with that knowledge. For centuries, we’d all pictured the novo- vacuum as the fireball from some terrible explosion. I came here myself in the hope that we might gain something from the challenge of learning to survive inside that fireball, but I never dreamed that the far side could harbor life of its own.

“Life does not arise easily in a universe of vacuum. Apart from the Earth, there are just four quarantined planets strewn with single-celled organisms, out of almost a million that have been explored. For twenty thousand years, we’ve clung to a faint hope that the Earth would not be unique as the cradle of sentience, and I don’t believe that we should abandon that hope. But we’re now standing at the border, not between a desert with rare oases on one side, and a lake of molten lava on the other, but between that familiar desert and a very strange ocean.

“This ocean might be a desert, itself. It might be turbulent, it might be poisonous. All we know for certain is that it’s not like the universe we know. But now we’ve seen something fluttering beneath the surface. To me, it looks like a beacon, a declaration of intelligence. I concede that this interpretation might be completely wrong. But if we’d ever spotted something a tenth as promising on a planet, wouldn’t we be shouting with joy, and rushing to investigate?

“The homes and communities of billions of people are at stake here. One full year’s delay would mean the certain loss of one more world.” Tchicaya had agonized over the best way to phrase this; apart from starkly requesting an entire planet as a sacrifice, he had to tiptoe around the issue of exactly how close the