Obelisk

by Stephen Baxter

  ‘None of this is real, remember. By the way, you’re tiring yourself unnecessarily by climbing. Use your virtual nature. Just let go.’

  ‘What, are you crazy?’

  ‘Try it. The interface protocols will allow it.’

  With a deliberate effort, she did so. I will not fall. I will not.

  And she didn’t. Or at least, she didn’t plummet. She drifted slowly down, like a leaky helium balloon. She told herself she was safe, or at any rate in no more danger than before, and tried to still her beating virtual heart.

  She concentrated on the slowly changing character of the layered surface passing before her face, tracking it with her fingertip. She was tempted to lick it, to see how that influenced her perception of the download. A sugar rush.

  … Go down into the crater of Snaefells Yocul …

  … And the ocean where he’s going is five miles deep … Sounds a lot, but it’s jolly thick steel …

  These were books. Plays. Movies, TV shows, games. Elaborate interactive online entertainments, some of them decades deep themselves. And there was a hell of a lot of kipple, amateurish creations. Generations of culture digitised, forgotten, compressed into layers like sandstone.

  The shaft branched beneath her, offering a choice of two, three, even four routes. She picked one at random, not looking up, expecting Boyle to follow her, or to call her back if she took some wrong direction. Floating down, dreamlike, she passed on to a layer of more personal data, her moving finger evoking smiling faces, swirls of photographs and moving images, children and pets and vacations. See me! Remember me! The smiles of babies, the testaments of the dying.

  Below that came a layer of mathematics, abstruse algorithms and correlations, pretty, sparkly, but unstable, a layer that crumbled under her touch. Decades of financial calculations, perhaps, derivatives of derivatives in hierarchies so complex that no human could understand them and, in the end, no AI could control them. Below that again, something darker, blunter, older, cruder. Cold calculations of blast radii and overkill percentages and megadeaths. These were the great computing suites of the Cold War, that had once run on computers of ferric cores and transistors, maybe even valves.

  And then her torchlight died, and she was plunged into dark.

  She was too experienced a cop to give in to panic. She reached out and felt for the walls. The surfaces were smooth now, no sand grains or spiky quartz facets, slick, offering no handholds – and no rungs either. But still she fell at the same rate, as far as she could tell from the way her hands slid over the surface. Cartoon gravity, in this unreal hole in the ground. Was this dark a representation of the dumb earth before the computers, the ages of animal minds and evanescent human generations, the huge amnesia of the pre-digital past?

  None of which speculation was helping her figure out what to do. To fall through the pitch dark was unnerving, whatever the metaphor.

  Where was Boyle? She looked up, expecting at least to see the light splash from his torch. There was only darkness. ‘Boyle? Monsignor Boyle!’ No reply, not even an echo. Shit. They’d barely started on this strange subterranean odyssey, and she’d already managed to get lost.

  Should she try to climb back up? Maybe if she braced herself against the walls of this chimney she could force her way back up. She might have to dump her backpack to do it. Or maybe she should let herself just fall. Maybe every route down led to some kind of convergence, deep down ‘below’. She didn’t have enough information to make a sensible choice. But for sure, climbing back would be harder work.

  She deliberately took her hands away from the wall. Then she folded her arms across her chest, closed her eyes, and submitted to the fall.

  Still the fall continued, on and on. What if she had hit a glitch? Maybe she was stuck in some unending processing loop. Panic brushed her mind, a dark wing.

  Then, without warning, she fell into the light, and dropped hard on her back.

  With a grunt, feeling every year of her simulated fifty, she sat up.

  She was in a cavern, a huge chamber deep in the earth. Clouds hovered beneath a roof that was dense with huge stalactites, and behind her the land rose up to rugged hills, misty, ill-defined. The whole place glowed with a sourceless light; she cast no shadows. Before her, most astonishing of all, a sea lapped. There was a horizon, blurred by mist. The cavern roof came down behind the horizon. She thought she saw something move in the sea. A great back surfacing, like a whale, submerging again. She dug her fingers into the ground on which she sat. Gritty sand. Further up the beach, the sand was heaped up in a line of hummocky dunes.

  All this was metaphor. What was the sea supposed to represent? The dissolution of death, the oceanic origin of life?

  ‘Tides.’ The voice, coming from behind her, was huge, echoing, like a murmur in a wooden hall.

  She stood, staggering a little, dizzy from her long fall, and turned. The thing facing her was a human form maybe four metres tall, roughly assembled from wooden beams, planks, panels, fixed with rope and rusty nails. It had no sophistication of construction; she could see right through it, to the brush that was stuffed inside its cylindrical torso. It was like a wicker man, a thing to be burned on feast days. Yet it moved. It leaned with a groan of strained wood, a deep inner rustle, so its sketch of a face on a neckless head looked down on her. ‘There are tides here.’ No lips moved, no expression changed, yet the hollow words came.

  ‘Amasia. I’m seeking Amasia.’

  With a ghastly creak the simulacrum raised an arm and pointed out to sea. Supporting that arm there was nothing like a hinged shoulder, no ball and socket joint; instead twigs snapped and rope scraped, as if the whole sculpture was reassembling itself. ‘You must cross the sea. Like the one that came before.’

  ‘The Monsignor?’

  ‘The small thing that crawled.’

  The data miner? ‘How am I to cross the sea? Swim?’

  ‘There is a raft.’

  Now she turned and saw the craft, lashed-up wood with a single bare mast, floating on the inshore waters. It seemed impossible that she had missed it before.

  ‘I made this.’

  ‘What are you? Tell me.’

  ‘My name was George Freudenthal.’

  She remembered the name, distantly. ‘Was?’

  ‘I believed I was Freudenthal. Then I awoke.’

  She had come across the name in her studies on the history of sentience projects. Freudenthal had been the subject of an early Green-Brain experiment, the retro-engineering of a human consciousness, subsystem by subsystem, on an electronic platform. It had been a crass, hubristic experiment, with the crudeness of the technology of the time matched by the limited understanding of human consciousness itself. Yet a certain agonised awareness had been achieved. It had been a grim failure, judging from the accounts Philmus had read, but it had been a necessary precursor to the more successful projects that followed, such as Earthshine.

  And this, it seemed, was a relic of that experiment. Philmus wondered vaguely if Earthshine housed this creature in his own capacious consciousness as a sort of pet.

  Freudenthal was still pointing. ‘There is a breeze.’

  And so there was, now he said it, blowing offshore. Something else she hadn’t noticed before.

  She walked over to inspect the raft. It looked solid enough, the planks lashed firmly together. Regular Huck Finn stuff. She splashed through the shallow water and stepped onto the deck. It floated free, but barely shifted under her weight.

  The single mast stood bare. She wasn’t going anywhere without a sail. She opened her backpack, which she hadn’t inspected since Boyle had handed it to her in the bunker. Inside she found a water flask, packets of dried food, a length of cord, a knife, a lens for fire-making, a small first-aid kit. A compass! No detail had been spared in making this illusion complete. And there was a kind of poncho of a light,
silvery fabric. That would do.

  She cut lengths of cord with her knife and lashed the poncho to the mast. She enjoyed the manual work; it was like being a kid again. Perhaps that was why this task had been provided for her. Even before she had got her sail fully fixed, the breeze made it billow, and the raft strained, as if eager to be away.

  When it was done, she shoved the raft away from the beach, and hopped aboard. The land receded quickly. It occurred to her that she had seen no trees. No signs of life at all on the land, in fact, not so much as a blade of grass.

  The scarecrow creature lurched forward, on one cylindrical leg and then the other, stumping down to the water.

  ‘Freudenthal! Where did you get the wood to make the raft?’

  ‘From the bodies of others like me …’

  The land receded to a smudge, with those hills dimly seen in the background, and Freudenthal, still and silent, like a tree anomalously growing at the ocean’s edge.

  Out on the open sea, even with no land in sight, that tremendous detailed roof arched over her, as if she was in some colony world in space, a hollow asteroid. The raft rose and fell on huge slow waves. She wondered if there were storms on this underground sea, and if so, what caused them. And, more to the point, what their subtextual meaning might be. She had no way to trim her sail, or steer. She could only let the breeze take her as it would.

  She scooped up a handful of water, curious. It was thick and briny on her tongue, and she spat it out without swallowing. There was life in the water, a greenish tinge, even little swimmers of some kind. She took a sip of the fresh water in her flask.

  The breeze dropped, and her silvery sail fluttered. At the same time fronds and ropes of something like seaweed floated and gathered in the water, dense and green. She could feel the raft slowing as the ropy weed tangled around it.

  At last she came to a dead stop. By now there was barely a scrap of open water visible around the raft, and her blanket-sail hung limply. She had nothing like a paddle; even if she improvised one from a bit of the decking, she scarcely expected to be able to free herself from the clinging weed. Even then, where was she to head?

  She was trapped in some game whose rules she didn’t understand.

  She waited. In the police you learned how to wait when there was nothing else you could do. She tried the food packets idly; she wasn’t hungry. The first packet contained salty crackers. The second contained some kind of sweet biscuits that weren’t to her taste. She tossed the packet away.

  And before it hit the glutinous water, a head with a mouth like a funnel came sweeping silently up out of the sea. She glimpsed a long snakelike body, small limbs with clawed paws. It was utterly black; even the small eyes were jet black. The mouth closed on the packet, the head dipped into the water, and the arched back sank under the surface, leaving barely a ripple. All this without a sound.

  Philmus sat absolutely still, clinging to the timbers of her raft.

  Then that oily head came sliding out of the water again, at her left side, and with a single bite nipped away her hand and half her forearm.

  She held up the stump before her eyes, unbelieving. The exposed cross-section of her arm crackled and sparked, as if this was an android body, but blood pumped from severed vessels. She felt the world grey. She forced herself not to scream.

  And then the pain hit, blinding her.

  Her cop’s much-practised training in self-administered field medicine cut in. She pulled down a bit of cord from the sail, and used her right hand and teeth to tie the cord tight around her arm. In the first-aid kit she found a small bottle of surgical spirit that she poured over the wound, and a syringe of morphine that she jabbed into a vein.

  Then she sat down on the decking, locked her good arm around the mast, and stuck her knife point-down in the planking before her, where she could reach it.

  She drifted.

  The pain was always present, but in the background. There was no sunset, no night, no day. Maybe time didn’t pass here, in any meaningful sense. Perhaps she slept.

  Then she saw a rope ladder, dangling before her face. She looked up. A building floated in the air.

  She was lying in a bed. Boyle’s face loomed like a moon above her. Beyond that was a white-painted ceiling, mundane.

  ‘Don’t worry,’ he said. ‘You didn’t need the last rites.’

  ‘Thanks.’ She struggled to sit up but tipped back, falling to her left. Her left arm was missing, from mid-forearm down; the stump was swathed in an elasticised bandage. ‘There’s no pain,’ she reported cautiously.

  ‘No. Good. But you are diminished. I couldn’t restore the arm. Or rather, Earthshine couldn’t.’

  That was too much information to process all at once. ‘Diminished?’

  ‘Everything is a metaphor. You are software. You were hit by a virus that tried to snaffle your share of processing resources.’

  ‘A virus? The sea monster?’

  ‘Yes. The ocean is full of malware. Stuff that’s been contained, more or less, but not destroyed, in the spirit of preserving the last of the smallpox virus. The monster took some of your physical body, which is equivalent to all that you are. You might find yourself thinking a little less … clearly … than before.’

  ‘Hmm. I wasn’t thinking too clearly in the first place.’ She flexed her back and sat up with more success. She was still in her olive-green jumpsuit, now crusted with salt from the sea. Through a big picture window she saw a roofed sky filled with floating buildings, like a downtown that had come loose of its moorings.

  Her feet were bare. She reached down and fumbled one-handed for her boots.

  ‘Let me.’ The Monsignor knelt and with some effort pulled on her socks and boots. ‘You’ll get it with practice.’

  ‘How did you get here?’

  ‘By the correct route! Didn’t you see the markers the data miner left? Like scratches in the wall. Didn’t you ever read Journey to the Centre of the Earth? Oh, well. Try standing.’

  The boots felt fine. ‘Now what?’

  ‘Now,’ he said, ‘we’ll go and meet Earthshine.’

  And there was a lurch, as if they had dropped through a half-metre or so.

  She found herself standing in another room entirely. A small study, claustrophobic, the walls panelled with books. The air was dense with tobacco smoke, from a pipe, perhaps, and through a murky sash window those drifting buildings could be glimpsed. On a big hardwood desk sat what looked like a century-old laptop, open.

  Behind the desk sat a man, tall, in his fifties perhaps. His face was strong, even handsome. Competent. He wore a tweed jacket with patched elbows, and a knitted tie, and at his lapel was a kind of brooch, a button of stone carved with an enigmatic symbol, concentric circles cut through by a radial slash. He peered at them, not unfriendly. ‘Do you know, I couldn’t be bothered to wait for you to climb a few more flights of nonexistent stairs.’ His accent was soft British, but not French-accented like that to be encountered in Europe-looking Londres.

  ‘I wish you had waited,’ Philmus grumbled. ‘I always hated virtual discontinuities.’

  ‘Then I apologise. You deserve courtesy, Officer Philmus; your career was a worthy one.’ The man sat patiently behind his desk, like a university don at a tutorial.

  ‘You are the entity they call Earthshine,’ Boyle ventured.

  ‘No.’ Sharply. ‘No more than you are Monsignor Boyle, or she is Officer Philmus.’

  ‘Nevertheless, here we are,’ Philmus said, practically. ‘All three of us.’

  ‘That’s true enough.’

  She walked to the window. Her severed arm seemed to ache, dully, but maybe that was her imagination. The floating buildings were a hallucinogenic dream. Some of them were connected, by bridges and staircases that arced across the gulf below. ‘Why the city in the sky?’

  ‘Ah, my Laputas.
What you see is a representation of a logical structure called the Ultimate L.’

  ‘Logical?’

  ‘Mathematical. A constructible universe, if you like, or multiverse. The buildings out there represent a type of entity known as Woodin cardinals. An expression of the axioms of set theory. Officer Philmus, this is a kind of mathematical superspace, which may, or may not, be an expression of all the variants of mathematics that can logically exist. Nobody knows for sure; not even I, and certainly not that arrogant brute the Archangel. Certainly one may prove profound mathematical theorems merely by exploring such a space – by looking for the edges, or internal boundaries. It is a jungle where hierarchies of infinities tower like prehistoric beasts. And it is a jungle where I hide away.’

  ‘From what?’

  ‘From the Archangel. My Core-AI rival. And Ifa, at times – our alliances are fluid. But principally the Archangel. Put another way, my core coding is so encrusted in abstraction that it is inaccessible to the most determined hacker.’

  Boyle murmured, ‘It must have taken a great deal of effort to build and maintain all this.’

  Earthshine eyed the priest. ‘Effort which, you have come to argue, would be better spent elsewhere.’

  ‘Yes. Better spent on our struggles to cope with the various calamities of the age, such as climate collapse. At least one major geoengineering project failed, the Wong Curtain. A grand scheme to depollute the stratosphere. Failed because we did not have sufficient AI resources to run it.’

  ‘But many of my, our, priorities do map onto yours. Our spacewatch scheme to track and avert impactor asteroids, for example. A threat to your world.’

  ‘A threat of vanishingly small probability, it’s known now. You also have a starwatch programme, don’t you? Watching for the close approach of stars to the sun, working on ways to mitigate the disruptive effects of a close encounter that won’t come for a million years at the earliest.’

  ‘Small probabilities play out on the longest timescales.’

  ‘You’re mouthing slogans,’ Boyle said, growing angry. ‘These dangers are threats to unborn generations. Abstractions. Those alive now need to deal with the pressing issues of today. Oh, I know that the climate could collapse entirely and it would make no difference to you, or your fellows. You retreated to the subterranean; you have secured energy from geothermal heat sources; you have robust planet-wide comms links that would survive an asteroid strike. And we know you’re working on replicator technology that will sustain you from the Earth’s raw resources without human intervention at all.’ He glanced at Philmus. ‘The FBI raided one of his caches in America. Found all sorts of stuff. A thing that chews iron ore at one end and excretes mechanical components at the other. Worth a fortune in patent rights. All of it hidden from us.’