Schild’s Ladder

Apart from Earth itself, native life had only been found on three worlds. Simple and microbial, but in each case unique. Every biosystem used different chemistry, different methods of gathering energy, different structural units, different ways of storing and transmitting information. On the crassest, most pragmatic level, this knowledge might be of little value: technology had long ago surpassed nature’s ability to do all of these things efficiently. But each rare glimpse at a separate accident of biogenesis cast light on the nature and prospects of life. The roof of this building would become the most talked-about location for a hundred light-years.

Tchicaya said, "What if it’s something we brought ourselves? That wouldn’t be much of a discovery."

"Such as what? Nothing we brought can mutate freely: every cell in every crop, every cell in our bodies, has fifty different suicide enzymes that kill off the lineage at the first genetic error. This could no more be ours than if they found some strange machine out in the ice that nobody owned up to making."

Tchicaya was growing tired of trying to keep his balance on the sloping roof; he sat down, his back slumped against the fin. It was lukewarm, body temperature. Once Slowdown ended, it would be hotter than the boiling point of water. So which extreme did the native life favor? Had it grown here before the Slowdown, and then managed to cling on in the relative cool? Or had it blown out of the icy wastes and only colonized the radiator once the Slowdown had rendered this tiny niche benign?

Mariama sat beside him. "We’ll have to leave," she said.

"Can’t that wait until morning?"

"I don’t mean us, now. We’ll have to leave Turaev. They’ll evacuate the planet. We’ll all have to go somewhere else." She smiled, and added with a kind of mock jealousy, "I always wanted to be the one to shake this place out of its stupor. But it looks as if you’ve beaten me to it."

Tchicaya sat motionless, scowling slightly. The words refused to sink in. He knew that she was right: it was a universal principle, accepted by every space-faring culture. In each of the other three cases, the planet in question had been strictly quarantined and left to its own fate. Only one of those worlds had been settled, though. Native life was supposed to have been ruled out, long before the colonists' first spores were launched. However microscopic, and however sparsely distributed, it should have left some detectable chemical signature in the atmosphere.

Tears stung his eyes. In his euphoria, he’d never thought beyond the unlikely confirmation that his own world, his own town, held the fourth known example of extraterrestrial life. He could have lived down the shame of this childish escapade, half-excused by that serendipitous discovery. But he’d been more than disobedient, more than disrespectful of the customs that bound the people of Turaev together. He’d destroyed their whole world.

He didn’t want to weep in front of Mariama, so he stammered out an incoherent stream of words instead. Everything he’d planned, everything he’d pictured for the future, had just turned to ashes. He might have traveled one day, like Erdal, but he would never have left his friends and family behind, never lost synch. Fifty-nine generations had made this planet their home; he could never belong anywhere else. Now it would all be torn away from him. And nine million people would suffer the same fate.

When he stopped to catch his breath, Mariama said soothingly, "Everything here can be moved! Every building, every field. You could wake up on New Turaev, a thousand light-years away, and if you didn’t check the stars you’d never know."

Tchicaya replied fiercely, "You know it will never happen like that! Five minutes ago, you were crowing about it!" He wiped his eyes, struggling not to turn his anger against her. He’d always understood what she wanted; he had no right to blame her for that. But any reassurance she offered him was hollow.

Mariama fell silent. Tchicaya buried his head in his hands. There was no escape for him: only adults had the right to shut down their Qusp, to choose extinction. If he threw himself from the roof and broke his spine, if he doused himself in oil and set himself alight, it would only make him more contemptible.

Mariama put an arm around his shoulders. "On how many worlds," she said, "do you think they’ve found life?"

"You know the answer. Three, since Earth."

"I don’t know that. There might have been ten. There might have been hundreds."

Tchicaya’s skin crawled. He looked up and searched her eyes in the starlight, wondering if she was testing him. What she was proposing now was infinitely worse than anything they’d done so far.

She said, "If you believe it will hurt so many people, so badly, then I’ll listen to you." Tears were trickling down his cheeks again; she wiped them away with the back of her hand. "I’ll trust you."