Axis

remember no other home. Her life before Bar Kea was little more than a story she had been told by her teachers: a story about a girl who had been washed away, along with her family, by a flood along the Paia River, and who had been rescued from the intake filter of a dam three miles downstream. Her parents had died and the small girl, this unremembered Sulean, had been so grievously wounded that she could only be saved by profound biotechnical intervention.

Specifically, the child Sulean had to be rebuilt using the same process that was used to extend life and create Fourths.

The treatment was more or less successful. Her damaged body and brain were reconstructed according to templates written in her DNA. For obvious reasons, she remembered nothing of her life before the accident. Her salvation was a second birth, and Sulean had relearned the world the way an infant learns it, acquiring language a second time and crawling before she took her first (or second) tentative steps.

But there was a drawback to the treatment, which was why it was so rarely used as a medical intervention. It conferred its customary longevity, but it also interrupted the natural cycle of her life. At puberty, every Martian child developed the deep wrinkles that made Martians appear so distinctive to Terrestrials. But that didn't happen to Sulean. She remained, by Martian standards, sexless and grotesquely smooth-skinned, an overgrown infant. When she looked in a mirror, even today, Sulean was inevitably reminded of something pink and unformed: a grub writhing in a rotten stump. To protect her from humiliation she had been sheltered and nurtured by the Fourths who saved her life, the Fourths of Bar Kea Desert Station. At the Station she had a hundred indulgent, caring parents, and she had the dry hills of Bar Kea for a playground.

The only other child at the Station was the boy named Esh.

They had not given him any other name, only Esh.

Esh had been built to communicate with the Hypotheticals, though it seemed to Sulean he could barely communicate even with the people around him. Even with Sulean, whose company he obviously enjoyed, he seldom spoke more than a few words. Esh was kept apart, and Sulean was allowed to see him only at appointed times.

Nevertheless she was his friend. It didn't matter to Sulean that the boy's nervous system was supposedly receptive to the obscure signals of alien beings, any more than it mattered to Esh that she was as pink as a stillborn fetus. Their uniquenesses made them alike and had thus become irrelevant.

The Fourths at Bar Kea Desert Station encouraged the friendship. They had been disappointed by Esh's refractory silences and his outward display of dull-normal intelligence. He was studious but incurious. He sat wide-eyed in the classrooms the adults had designed for him, and he absorbed a reasonable amount of information, but he was indifferent to it all. The sky was full of stars and the desert was full of sand, but stars and sand might have traded places for all it mattered to Esh. Whether he spoke to the Hypotheticals, or they to him, no one could say. He was stubbornly silent on the subject.

Esh was at his liveliest when he was alone with Sulean. They were allowed to leave the station on certain days to explore the nearby desert. They were supervised, of course—an adult was always within sight—but compared to the closeted spaces of the Station this was wild freedom. Bar Kea was formidably dry, but the scarce spring rains sometimes pooled among the rocks, and Sulean delighted in the small creatures that swam in these short-lived ponds. There were tiny fish that encased themselves in hibematory cysts, like seeds, when the water dried, and sprang back to life during the rare rains. She liked to cup the populated water in her hands, Esh watching with silent wonder as the wriggling things slipped between her fingers.

Esh never asked questions, but Sulean pretended he did. At the Station she was always being taught, always being encouraged to listen; alone with Esh she became the teacher, he the rapt and silent audience. Often she would explain to him what she had learned that day or week.

People had not always lived on Mars, she told him one day as they wandered among sunlit, dusty rocks. Years and centuries ago their ancestors had come from Earth, a planet closer to the sun. You couldn't see Earth directly, because the Hypotheticals had enclosed it in a lightless barrier—but you knew it was there, because it had a moon that circled it.

She mentioned the Hypotheticals (called by Martians Ab-ashken, a word compounded of the root-words for 'powerful' and 'remote'), cautiously at first, wondering how Esh would react. She knew he was part Hypothetical himself and she didn't want to offend him. But the name provoked no special response, only his usual blank indifference. So Sulean was free to lecture, imagine, dream. Even then the Hypotheticals had fascinated her.

They live among the stars, as far as anyone knows, she told the boy.

Esh, of course, said nothing in return.

They're not exactly animals, they're more like machines, but they grow and reproduce themselves.

They do things for no apparent reason, she told him. They put the Earth inside a slow-time bubble millions of years ago, but no one knows why.

No one has talked to them, she said, unless you have, I suppose, and no one has seen them. But pieces of them fall out of the sky from time to time, and strange things happen…

* * * * *

Pieces of them fall from the sky: this last piece of information caused considerable consternation among Dr. Dvali's Fourths.

Dvali cleared his throat and said, 'There's nothing about such an event in the Martian Archives.'

'No,' Sulean admitted. 'Nor did we ever mention it in direct communication with the Earth. Even on Mars it's a rare occurrence—something that happens once every two or three hundred years.'

Mrs. Rebka said, 'Excuse me, but what happens? I don't understand.'

'The Hypotheticals exist in a kind of ecology, Mrs. Rebka. They bloom, flourish, and die back, only to repeat the cycle again, over and over.'

'By the Hypotheticals,' Dr. Dvali said, 'I presume you mean their machines.'

'That may not be a meaningful distinction. There's no evidence that their self-reproducing machines are under the control of anything but their own networked intelligence and their own contingent evolution.

Naturally, the detritus of their lives circulates through the solar system. Periodically the debris is captured by the gravitation of an inner planet.'

'Why haven't these things fallen on the Earth?'

'Before the Spin the Earth existed in a much younger solar system Five billion years ago the Hypotheticals had barely established themselves in the Kuiper Belt. If their machines did occasionally enter the Earths atmosphere it would have been an isolated, rare event. There are enough reports of hovering lights or strange aerial objects to suggest that perhaps it did happen, now and then, though no one recognized it as such. When the Spin barrier was put in place it excluded any such fall-through, and even now the Earth is protected from the excessive radiation of the sun by a different kind of membrane. Mars, for good or ill, is more exposed. Martians didn't arrive in the modern day as strangers, Dr. Dvali. We've grown and evolved for millennia with the knowledge that the Hypotheticals exist and that the solar system is, in effect, their property.'

'The ash that fell on us,' Mrs. Rebka said, her voice throaty with a kind of hostile urgency, 'was that the same phenomenon?'

'Presumably. And the growths in the desert. It's only natural to assume that this solar system has also hosted Hypotheticals for countless centuries. The annual meteor showers are more likely their detritus than the simple remains of ancient rocks. The ashfall was just a particularly dense example, perhaps from a recent exfoliation. As if we had passed through a cloud of, of—'

'Of their discarded cells,' Dr. Dvali said.

'Cells, in a sense, shed, perhaps discarded, but not necessarily inert or entirely dead. Some partial metabolism persists.' Hence the ocular rose and the other abortive, short-lived growths.

'Your people must have studied these remains.'

'Oh yes,' Sulean said. 'In fact we cultivated them. Much of our biological technology was derived from the study of them. Even the longevity treatment is remotely derived from Hypothetical sources. Most of our pharmaceuticals entail some element of Hypothetical technology—that's why we grow them at cryogenic