Climbing the Blue by Stephen Baxter

Everything about our world is made,” said the Natural Philosopher. “Made by intelligence, perhaps even built by human hands! Tonight I will prove it to you — prove it, at least, to those with minds flexible enough to understand…”

To Celi, to any Foron, such thoughts were radical, shocking. But Celi was electrified.

Celi had only taken Vala to the lecture that night because he had heard rumors that the Philosopher was going to cut up a body. A human body, sliced apart in Foro’s own town hall! It was a sight no self-respecting sixteen-year-old could miss.

Celi’s father, Sool, had given his permission in his usual absent way. After all, he was going too. But his mother had seen right through him, as always. Pili was kneading bread, her powerful arms coated in flour. “You’re going because you think it will be some kind of circus. Blood and bone and guts.”

Immersed in rich kitchen smells, Celi squirmed, ashamed. “Mother, it’s not like that — “

“She’s a bad influence, you know.”

“Who?”

“Vala. Her Effigy has yours by the throat, doesn’t it? And she has you climbing the blue at a snap of her fingers.”

Climbing the blue. On Old Earth, time was layered: the higher you climbed, up towards the blueshifted sky, the faster time passed. So, said the more serious citizens of Foro, if you burned up your life on nonsense, you were climbing the blue.

Celi didn’t know what to say.

Pili sighed, and cuffed his head gently. “Go, go. But if you only have eyes for Vala, at least keep your ears open. You might learn something, and then the evening won’t be a total waste. But get the flour out of your hair first.”

So off he had set, at a run, to Vala’s house.

And as it happened he did learn something that night: something about the world he lived in, and about himself.

HuroEldon, Natural Philosopher, stalked back and forth over the stage in his richly woven robe, casting flickering shadows by the light of the torches on the walls.

The setting was magnificent. The town hall was a domed chamber, big enough to hold all Foro’s adult citizens. It was actually a wing of a palace, ruined in the Formidable Caress. Now it had been rebuilt, and not as the home of a ruler, but as a meeting place for all Forons, rich and poor.

But even here HuroEldon’s voice resounded like Lowland thunder, Celi thought, a voice too large to be contained by mere stone. The Philosopher had about him a rich whiff of antiquity: it was a strange thought that though Huro looked no older than fifty, he might have been born centuries ago.

And as he made his prefatory remarks, on the stage beside Huro were two bodies, corpses strapped to tables, covered by dust sheets and attended by assistants. Celi felt deeply queasy.

“The world is a made thing,” Huro said again. “An extraordinary claim that requires extraordinary evidence — and I have it!” With a showman’s flourish he drew a long knife from his sleeve, and his assistants pulled the cover sheets from the tables.

The audience gasped. One revealed corpse was of a young spindling, its six legs splayed, its long neck limp as string. And the other corpse was of a little girl.

Celi felt Vala’s hand creep into his own. He had actually known the child; she had been called Bera, and she had died of the Blight, aged only eight. Celi could see the disfiguring burn-like stains on her skin. Celi was ashamed at his earlier grisly curiosity: it made a big difference when you knew who was to be cut up.

HuroEldon held up his knife, inspecting the blade. Then with a butcher’s casual expertise, he slit the girl’s pale body from throat to pelvis and emptied its chest cavity of organs. There was a smell of sour chemistry; the body’s blood seemed to have been dried to a powder, and the organs were shriveled, like blackened fruit. But still people groaned, and a few stumbled out of the hall, their hands pressed to their mouths.

Huro displayed the essentials of Bera’s bone structure, the long spine, the ribs, the limbs attached by ball-and-socket joints. “Thus the architecture of a human,” he said. “And if you were to dissect a rat or a bird you would find much the same body plan — adjusted for the purpose of running or flying, of course, but displaying an essential unity of design.” Despite his revulsion, Celi was fascinated by this brisk lesson in skeletal anatomy.

Huro turned his back on the girl and stalked to the other table. “A spindling, though, is quite different. Why, you can see it even before I open it up. Look at it! Six legs. Six limbs, not four! And if we look deeper, we will find more divergences…”

Efficiently he peeled back skin and prized out bones from the spindling’s once-elegant long neck — except that these grayish objects weren’t actually bones. “The spindling has an inner skeletal structure. That much we have in common with it. But look — can you see?” He stalked around the front rows of the audience, who flinched back from his gory specimens. “This isn’t bone. It’s a kind of cartilage, quite unlike the human design.”

He tore apart the spindling, displaying more features of the animal. For instance, a human’s digestive system was essentially a duct that passed through the body: food in one end, waste the other. A spindling had a closed loop, so it used its mouth as its anus, for food and for waste. Celi was struck by this observation. Everybody knew to keep out of the way of a spindling when it prepared to vomit up its shit, but it had never occurred to him before how different it was to the human way of doing things. He felt curiosity stir; he wondered how many other strange features of the world were waiting for him to notice them, if only he could learn how to look.

“What does all this mean?” Huro demanded. “It means that the spindling does not come from the same tree of life as humans and rats and birds. The spindling has been brought here, to this world of ours, from somewhere else — or else we have been brought to its world, although that seems less likely as there are more creatures like us than like it. And the spindling is not the only example of an alien among us, among the plants and the animals.

“Like most primitive cultures on the Shelf, you Forons cling to a naive naturalism! You believe that the world as we experience it emerged from the blind operation of natural laws, that intelligence had no hand in it. But that cannot be true. The spindling is proof that the world could not have developed organically; one counter-example is enough to demonstrate that nature lacks the necessary unity for that to be so. The simplest hypothesis is in fact that it has all been made, all shaped by intelligence, from blueshifted sky to redshifted Lowland.” He held up spindling cartilage, and a hip joint from poor Bera. “Here is the proof!” And he threw the bones to the floor.

There was a long silence. Then one man rose to his feet. Celi was moved to see that it was his own father. Sool was a proud Foron clearly who bristled over Huro’s comments about primitivism and naivety. He demanded to know if this “radical creationism” was the only philosophical choice. Must Forons now accept gods and devils? Must they cower from storms like their ancestors, and worship the light that flared across the Lowland? Was not Huro’s presumption of a higher intelligence actually the more intellectually primitive point of view? He spoke well, a dignified anger deepening his voice, and his neighbors applauded.

But Huro was able to counter him point by point. Despite himself, Celi found himself accepting the Philosopher’s arguments. He felt deeply disturbed at the way this arrogant man dismissed his father, and had so easily upset his own worldview.

On impulse Celi stood up himself.

His father, surprised, yielded the floor. As he became the focus of the packed hall — the Mayor herself was here — Celi quailed. But he held his nerve, and dramatically pointed at Bera’s corpse. “Philosopher, if you can tell us the design of the whole world, why could you not save her from the Blight?”

Huro smiled. “If you ask such a question, young man, perhaps you have it in you to become a doctor, so you can answer it yourself. Talk to me later.” He turned away to take more questions.

As Celi sat down, stunned, Vala tugged his sleeve. “You won’t go to that awful man, will you?”

“No,” said Celi immediately. “No, of course not.” But as he stared into Vala’s wide blue eyes, he knew he was lying.

Foro was situated on the side of a cliff, on a broad plain called the Shelf. The Forons were proud of their town, for they had built it with their own hands. But it was cupped in the mighty ruins of a much older city, devastated generations ago by the Formidable Caress.

And if you climbed the rocky walls above and below the Shelf, you climbed into stratified time. You could ascend into a rarefied air where time raced like a pumping heart, or go down into the grave torpor of redshift.

In practice nobody from Foro ever did climb the rocks. It just wasn’t practical to run your life with time’s cogwheels slipping constantly. And the Forons’ reluctance was cultural too. Celi’s people were proudly descended from a group who had been kept in an up-cliff community called the Attic, where their lives had been burned up in the service of slower-living rich folk on the Shelf below. Celi was the great-grandson of rebels against that strange enslavement.

But if the folk of Foro ignored the stratification of time, the Philosophers, like HuroEldon, exploited it.

The Philosophers marketed knowledge. In their own community far down the slope, their lives, slowed by time, were stretched out. The Philosophers devoted their extended existences to recovering some of the wisdom that had been lost during the Caress, through study and patient archaeology. And they made their living by selling that learning back to those who had lost it. Thus HuroEldon had ascended grandly from his redshifted keep to instruct the people of Foro on how to turn their growing town from a heaped-up clutter into a functioning city with common services like water supplies, how to reclaim the ancient canal system to irrigate their fields, and so on; he could then step forward across time to advise on such projects as they were carried out.

Celi came to realize that this gift of knowledge was essential. It was only a few generations since Forons had begun to grope their way out of the fog of fearful superstition that had been the legacy of civilization’s fall in the Formidable Caress. And it was even less time since the deeper psychological shock of that fall had begun to fade: the edge of the Shelf was still lined by the remains of funeral pyres, where the citizens of Foro, despairing of a future in which another Caress must inevitably shatter all they had built, had burned all their learning with them when they died.

But however useful his advice, for Forons, who prided themselves on their egalitarian instincts, it was hard to stomach Huro’s arrogance. That lecture on creationism had been a gift by Huro, rich with too much knowledge, a bauble tossed carelessly away by a man come to advise on sewage.

And Huro deflected Celi’s young life just as casually.

In the end Celi did speak to the Natural Philosopher after the lecture. And within days he was assigned to Dela, the town’s physician, to begin his apprenticeship as a doctor. It all happened so quickly, his whole life diverted. When he thought this over Celi found he resented it, but he knew he would not take one step off the path he had chosen — or rather, that the Philosopher had chosen for him.

But when HuroEldon called on him, long after that fateful night in the town hall, Celi found it hard to hide his nervousness.

HuroEldon walked grandly through Celi’s study. In his Philosopher’s cloak, Huro was magnificent in this shabby background. He inspected Celi’s notes, carefully scraped onto spindling-skin parchment, and pored over an area he called Celi’s “laboratory,” an array of herbs, fluids, and minerals labeled and annotated.

Five years had worn away. Celi, now twenty-one, was growing into his role in the town, as a practicing physician — and as husband to Vala, and expectant father of her first baby. But for HuroEldon, who had returned to his redshifted community of Philosophers, less than a year had passed.

“I’m grateful that you called on me,” Celi said stiffly.

“I wanted to see how the town’s bright-eyed young doctor is progressing. It is always amusing to skip forward in time, so to speak, and see how such stories as yours have played out.”

“I’m not a doctor yet,” Celi said. “I’m still learning.”

“That will never cease, I hope.”

“And Dela is still working — “

“That old witch! Oh, Dela has the charm; she knows the right words to murmur when Effigies go spiraling up from the dying. But you have something far more important than that.” Huro tapped Celi’s temple. “A mind, my boy. That and your spirit, your doggedness. I saw it in you even during that night in the town hall.”

“I’m surprised you remember it…” But for Huro it wasn’t long ago at all. “Your lecture made a great impression on me.”

“Obviously,” Huro said dismissively.

“It wasn’t you showing off your knowledge that intrigued me,” Celi said, irritated. “It was Bera.”

“Who? — oh, the little girl on the butcher’s slab. What use is all the knowledge in the world, you asked, if it can’t save a child from the Blight?” He waved a hand at Celi’s homemade laboratory. “I can see you’ve devoted yourself to the cause. But the Blight won’t be wrestled into submission, will it?”

No, it wouldn’t. That was why Celi had asked to see HuroEldon.

Celi was already a competent physician. He could deliver babies, stitch up wounds, set broken limbs, and comfort the dying, and he had acquired basic knowledge of the vectors of infection, of antisepsis and antibiotics. Much of this learning, preserved and sold by the Philosophers, was rumored to be very old.

But Celi had also learned that there was nothing anybody could do about the Blight.

It showed up as a skin discoloration first, like a burn. This stage could last a year, even more. But eventually it got into your lungs, and within three days you were dead. None of Dela’s medicines could fight it; it was only rigid quarantine procedures that kept it from overwhelming the community altogether.

What frustrated Celi was that he was sure a cure for the Blight was achievable. As he had visited case after case, Celi made notes of the folk medicines he encountered, concocted from animal blood, plant roots and seeds, mineral salts — potions and salves born out of desperation. The surprising thing was that some of these remedies showed signs of slowing the disease. Somewhere in all these ingredients was a cure, he became convinced.

But finding that cure was a tremendous problem. There were no full-time scientists here; Foro wasn’t rich enough to afford them. And a little systematic thought demonstrated that there were simply too many combinations of ingredients and relative concentrations to be tested in less than a lifetime, even if he were to dedicate himself to the project full time — which, as he was one of Foro’s only two doctors, was quite impossible.

And now HuroEldon, who he had hoped would be a source of old wisdom on the Blight, dismissively told him it was all a waste of time anyhow. “We live in a world in which time is stratified, remember. Time flows faster the higher you go — “

“I understand that,” Celi said testily.

“Do you? That’s impressive. I don’t. And you must also understand, my boy, that organisms change — especially the pesky little brutes that bring us diseases. The Blight can transmit itself through blood, or spittle, or through the air. Whatever we do, a subset of the Blight’s disease vectors can always waft up into the blue where, accelerated in time, they can mutate, faster than we can hope to match them with our remedies. You see? It’s thus a fundamental feature of our world that disease is always beyond our control.” He shrugged massive shoulders. “One must simply accept the losses.”

Celi could not fault the Philosopher’s logic. But on some level, he saw, Huro simply did not care that it was impossible to defeat the Blight. Perhaps this was a legacy of the past. HuroEldon’s very name was a relic of the complicated compound nomenclature once adopted by the aristocracy of Foro, while Celi’s was a blunt Attic name. Even generations after the rebellion, in Huro’s heart he still thought he was better than Celi, and the swarming townspeople he tended. Celi kept such thoughts to himself.

Huro seemed to be growing bored. “You’re wasting your time here, you know. There are much more intriguing questions for a mind like yours to address.”

“Such as?”

“Such as the subject of that lecture of mine: the indisputable fact that the whole of our world is a made thing, or at least assembled from disparate components, from blue to red, top to bottom. We’ve plenty of evidence beyond spindling skeletons. Why, we believe that the very stratification of time is an artifact.”

Celi walked to the window and peered up at the sky. The light of Old Earth came from the shifting glow of the Lowland, reflected from the clouds; through those clouds Celi could see stars wheeling by, sharply blueshifted. “Why would anybody make all this?”

“Think it through,” Huro said. “If you could climb down from the stars, down into this redshifted pit we call our world, you would be preserved, locked in time, while the stars wheeled and died over your head.”

“Preserved?”

“We believe that once Earth was a world without this layering of time, a world like many others, perhaps, hanging among the stars. And its people were more or less like us. But Earth came under some kind of threat. And so, to protect their children, the elders of Earth pulled a blanket of time over their world and packed it off to the future. You must understand this is a rather flimsy hypothesis, and as I always say myself, extraordinary claims require extraordinary proof, and we don’t have it yet! But it’s the best justification we’ve come up with yet: Earth is a jar of time, stopped up to preserve its children.”

Celi frowned. “But then, what about the Effigies?” The ghostly forms released by the dying represented the biggest single mystery he had encountered as a doctor. “Are they us — are they human souls, leaving a dying body? And if so, why do so few of us release them on death? And why should the world periodically shake itself to pieces in the Formidable Caresses?”

“Good questions. I wish I had good answers! Perhaps you will find out for yourself — when you come down into the red and join us.”

So here was the invitation, bluntly stated. Celi said, “I am a doctor. I have patients here in Foro.”

“They will die in the end, whatever you do. While you could live on.”

“I have a wife. Vala. She is carrying our first child — “

“The blue-eyes who was with you the night of the lecture? How cute. Bring her with you. Or, better still, leave her behind.” He leaned closer, and Celi smelled gin on his breath. “Stride into the future with me, five years, ten, twenty. There will always be more girls, not even conceived yet, fresh fruit waiting to be plucked. How do you think I keep myself entertained during these visits to your dismal little town? It isn’t all sewage and creationism, you know.”

The curiosity Huro had woken in Celi that night five years ago would never leave him. But everything else about Huro and his proposal repelled Celi, everything but the allure of knowledge. It was easy for him to turn down Huro’s invitation.

But as it turned out, Celi’s future was after all decided that day. When he returned home, he found Vala sitting alone, stroking her belly, her face streaked by desolate tears. A pale pink stain, like a burn, was spreading across her cheek: it was the Blight.

Her life and his had been destroyed, he thought, by a vector of infection he couldn’t even see, and which he would never have the time to defeat. He couldn’t bear it.

It took a sleepless night of calculation for Celi to decide what he must do. He would not follow HuroEldon into the red. He must climb up into the blue, alone.

In the morning he packed quickly: a few clothes, some dried food, bags of seeds and roots, a set of his medicinal samples. Then, with his pack on his back, and a cage of mice dangling awkwardly from his belt, Celi walked out of Foro.

He made for the cliff face, and began to climb. Once there had been an elevator system here, worked by tethered spindlings. Now you had to walk. But a whole series of staircases bit into the face of the rock, heavily eroded by usage and weathering. He was winded by the time he had climbed the nine hundred steps to what remained of the Attic, where once his ancestors had toiled.

He walked around curiously; he had never been up here before. There was nothing left but post-holes in the ground, the scorch-marks of abandoned hearths, and gaunt caves in the cliff walls that had once been used as kitchens and dormitories. It all looked much older than the two or three generations since its abandonment, but that was in Foro time; up here in the blue this place had grown much older than the Forons’ memories of it.

He dangled his legs over the edge of the cliff, sipped water from a spring, and looked down into the depths of the Lowland, an ocean of misty redshift. From here, Foro too was bathed in a crimson glow; he could see the people and their spindling-drawn vehicles crawling as if through syrup. Already he was cut off from his family, from his patients, from Vala, by the streaming of time. He wondered how many of them he would see again.

Once he had made his decision to leave he had been determined to keep his plan secret from everybody — even from Vala. Perhaps it had been the kindest thing to do; or perhaps he had feared his own determination might waver if he hesitated.

But Dela, the doctor who had tutored him, had seemed to have an idea what he was up to. “It’s the white mice,” she told him.

“What about them?”

“Mice can catch the Blight, like humans. Spindlings, for instance, can’t. And that’s important to you, isn’t it?”

“I don’t know what you’re talking about.”

Unexpectedly she hugged him. Old enough to be his mother, she was a nurturing doctor, but not given to physical displays of affection. “I will miss you. You’re a good colleague.”

“I’ll be back in a few days.”

“Of course you will.”

His father had accepted his bland assurances that he would return. He had a more strained encounter with his mother, who, with her usual acuity, guessed he was up to something. “I always did say that girl would have you climbing the blue.”

“Look after her, Mother.”

“I will.” He embraced her; she smelled of warm bread.

And then had come his parting from Vala. He had left her, and his unborn child, with lies. Now, as he looked down into the layers of time that trapped her, he couldn’t bear even to think about it. Wearily he collected his kit and continued the climb.

Above the Attic he plodded steadily along the trails of migrant animals, and when the trails petered out, scrambled over rocks. There were no more people or animals, but he saw the flash of wings, and occasionally heard an echoing caw. He was not alone, not while the birds flew with him.

After a time he noticed a change in the rock. Shattered by frost or heat, its surfaces scarred by lichen, it seemed much more sharply eroded than the cliff faces down by Foro. The stratification of time must be having a profound effect on the very fabric of the world, with higher rock sections eroding away much more rapidly than lower. When he paused to sleep, wrapped in a skin blanket on a narrow ledge, he scratched a note about this in his spindling-skin journal, the first note he had made there.

On the third day he climbed a narrow pinnacle, heading up to a summit. By now it seemed that only he existed in a normal stream of time; he was alone in the clean, thin air, sandwiched between the wheeling stars over his head and the crimson glow beneath.

The slope leveled out, and he stood on a smooth, worn plateau. There was life here: tufts of grass, low trees that clung to the rock face, even a couple of abandoned birds’ nests. Food and water: he could live here, then. But Foro and the Shelf, far beneath him, were lost with the Lowland in a dank sea of redshift. Perhaps there were higher mountains to climb. But surely he had come high enough to achieve the temporal advantage he sought, high enough to defeat the evolutionary enthusiasm of the Blight vectors — high enough to give him the time he needed to save Vala. This would do.

But now that he had stopped moving, doubt plagued him. Could he really bear to lose himself in time like this?

Better not to think about it. Better to begin work; once his patient methodology gathered momentum his soul would be filled with the work, and his purpose. Grimly he began to unload his kit.

Celi stood in the doorway of the home he had built with Vala. He looked round at the walls of mud and plaster, the furniture they had made and bought, the carving with their names over the door. All of it was a lifetime old, yet as fresh as a morning. And there was no place for him, he knew.

He felt an odd stab of nostalgia for his mountaintop refuge, the hut he had built, the cages for the mice. But even if he could climb back up there it would all be gone, weathered away by accelerated time. The core of his life had been hollowed out; he felt as if he had been away only a moment, that he had been aged in a heartbeat.

Vala walked into the room, humming, a towel around her hair. For a moment she did not see him, and he watched her, his breath catching in his throat. It hurt him to see what the Blight had done to her: a crimson stain had spread up from her neck across her once-pretty face. Yet he was relieved that he had, after all, returned in time to save her.

Then she saw him. She recognized him immediately, and her blue eyes widened. It was unbearable to have her look at what he had become, with his white hair, his stooped back.

He longed to hold her, but time stood between them like stone. Only a year had passed for her, while more than forty had worn away for him.

“You said you would be gone a few days,” she said. “Some ‘few days.’”

“I’m sorry,” he said. “Vala, the baby — “

“You have a son, Celi. A son. Four months old.”

He tried to take that in. His leathery old heart beat faster. He held up his precious vial. “Take this. It is — “

“I know what it is. Your mother guessed what you must be doing. So did Dela. Oh, you fool! What use is saving me if I had to lose you in the process?”

He pressed the vial into her hand. “Take it to Dela,” he whispered. “She will know what to do. Hurry now. It’s what all this has been about, after all.”

She bit her lip, and ran out of the door.

And HuroEldon walked in, his robe sweeping. “Well, well. Somebody told me they saw you come staggering back down out of the blue.”

Celi straightened. “Philosopher.”

Huro leaned closer. “You smell like a spindling’s breath. And what is this you’re wearing, mouse fur? I take it you found your cure.”

“Oh, yes.” And the Blight, once cut off from its human host and eliminated, could never be resurrected, even by stratified time.

“I knew you would do it,” Huro said grudgingly. “But I never thought you would reduce yourself to this in the process. And you ran out on your patients, despite the vows you doctors take.”

“I came back — “

“But what use are you now, like this?” He inspected Celi, as if he were a curious specimen. “Your wife can’t love you again, you know. We humans don’t seem to have evolved to handle such differential shifts in time. That’s another point that convinces me this is a made world, by the way, that we are designed for a different environment…. “He idly picked up Celi’s notebook, and paused at the very first note Celi had made so long ago, about the effects of differential weathering rates. “An acute bit of geology. I told you, you would have made a good Philosopher. But you’ve thrown your life away.”

Celi had no reply. Huro was articulating doubts that had plagued him during his vigil on the mountain — in all those years alone, how could he not have had doubts? As he had worked through his monumental combinatorial challenge with his vials of infected blood and trial remedies, slaughtering generation after generation of white mice, his intellectual curiosity, even his basic impulse to save his wife, had worn away, leaving nothing but a grim determination to keep on to the end. He had even stopped counting the years as they had piled up. Of course he had been lonely, up there on his plateau, looking out over uncounted layers of time! But what choice had there been?

Well, he had succeeded, and he must not let Huro stir ancient doubts in his soul. “You Philosophers exploit the time strata selfishly — “

“While you have burned up your own life to save others. Yes, yes. You aren’t the first, you know; your heroism isn’t even original.” Huro peered into Celi’s eyes, his mouth. “You might have found your Blight treatment up there, Celi, but you sacrificed your own health in the process. I’d give you a year. Two at the most.”

“It doesn’t matter.”

“No, I don’t suppose it does to you, does it?” Huro’s expression softened, just a little. “My offer still stands.”

“What offer?”

“To come with me, downbelow. You may only have a year, but spin it out! Some of us are planning to go on, you know.”

“Go where?”

“Down into the red. Nobody knows how deep we can go, how much we can stretch time before it snaps like an overextended sinew. Some of us dream of pushing on into the future, all the way to the next Formidable Caress. And if we can do that, who knows what’s possible? Come with me, Celi. You’ve given up almost all of your life. Surely you owe yourself that much.”

But Celi heard a sound from a neighboring room. It was a soft gurgle, the cry of a waking baby. “I have all I need here,” he said.

HuroEldon snorted. “Well, we won’t meet again. The time streams will see to that.” The Philosopher walked out of the house.

And Celi, broken and old, went to comfort his infant son.

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