by Greg Egan
Yatima had persisted. “You could make the programs more sophisticated. More discriminating. Let them generalize from examples, form conjectures ... aim for proofs.”
Radiya had conceded, “Perhaps it could be done. Some fleshers tried that approach before the Introdus — and if you’re short-lived, slow, and easily distracted, it almost makes sense to let unthinking software find the lodes you’d never hit before you died. For us, though? Why should we sacrifice the opportunity for pleasure?”
Now that ve’d experienced Truth Mining for verself, Yatima could only agree. There was nothing in any scape or library file, any satellite feed or drone image, more beautiful than mathematics. Ve sent the scape a query tag, and it lit the way to the Gauss-Bonnet Theorem with an azure glow for vis viewpoint only. Ve floated off slowly down one of the tunnels, reading all the tags from the jeweled path.
Learning was a strange business. Ve could have had vis exoself wire all this raw information straight into vis mind, in an instant — ve could have engulfed a complete copy of the Truth Mines, like an amoeba ingesting a planet — but the facts would have become barely more accessible than they already were, and it would have done nothing to increase vis understanding. The only way to grasp a mathematical concept was to see it in a multitude of different contexts, think through dozens of specific examples, and find at least two or three metaphors to power intuitive speculations. Curvature means the angles of a triangle might not add up to 180 degrees. Curvature means you have to stretch or shrink a plane non-uniformly to make it wrap a surface. Curvature means no room for parallel lines — or room for far more than Euclid ever dreamt of. Understanding an idea meant entangling it so thoroughly with all the other symbols in your mind that it changed the way you thought about everything.
Still, the library was full of the ways past miners had fleshed out the theorems, and Yatima could have had those details grafted in alongside the raw data, granting ver the archived understanding of thousands of Konishi citizens who’d traveled this route before. The right mind grafts would have enabled ver effortlessly to catch up with all the living miners who were pushing the coal face ever deeper in their own inspired directions ... at the cost of making ver, mathematically speaking, little more than a patchwork clone of them, capable only of following in their shadows.
If ve ever wanted to be a miner in vis own right — making and testing vis own conjectures at the coal face, like Gauss and Euler, Riemann and Levi-Civita, deRham and Cartan, Radiya and Blanca — then Yatima knew there were no shortcuts, no alternatives to exploring the Mines firsthand. Ve couldn’t hope to strike out in a fresh direction, a route no one had ever chosen before, without a new take on the old results. Only once ve’d constructed vis own map of the Mines — idiosyncratically crumpled and stained, adorned and annotated like no one else’s — could ve begin to guess where the next rich vein of undiscovered truths lay buried.
Yatima was back in the savanna of vis homescape, playing with a torus crisscrossed with polygons, when Inoshiro sent a calling card; the tag entered the scape like a familiar scent on the wind. Yatima hesitated — ve was happy with what ve was doing, ve didn’t really want to be interrupted — but then ve relented, replying with a welcoming tag and granting Inoshiro access to the scape.
“What’s that ugly piece of crap?” Inoshiro gazed contemptuously at the minimalist torus. Ever since ve’d started visiting Ashton-Laval, ve seemed to have taken on the mantle of arbiter of scape aesthetics. Everything Yatima had seen in vis homescape wriggled ceaselessly, glowed across the spectrum, and had a fractal dimension of at least two point nine.
“A sketch of the proof that a torus has zero total curvature. I’m thinking of making it a permanent fixture.”
Inoshiro groaned. “The establishment have really got their hooks into you. Orphan see, orphan do.”
Yatima replied serenely, “I’ve decomposed the surface into polygons. The number of faces, minus the number of edges, plus the number of vertices — the Euler number — is zero.”
“Not for long.” Inoshiro scrawled a line across the object, defiantly bisecting one of the hexagons.
“You’ve just added one new face and one new edge. That cancels out exactly.”
Inoshiro carved a square into four triangles.
“Three new faces, minus four new edges, plus one new vertex. Net change: zero.”
“Mine fodder. Logic zombie.” Inoshiro opened vis mouth and spewed out some random tags of prepositional calculus.
Yatima laughed. “If you’ve got nothing better to do than insult me ...” Ve began emitting the tag for imminent withdrawal of access.
“Come and see Hashim’s new piece.”
“Maybe later.” Hashim was one of Inoshiro’s Ashton-Laval artist friends. Yatima found most of their work bewildering, though whether it was the interpolis difference in mental architecture or just vis own personal taste, ve wasn’t sure. Certainly, Inoshiro insisted that it was all “sublime.”
“It’s real time, ephemeral. Now or never.”
“Not true: you could record it for me, or I could send a proxy —”
Inoshiro stretched vis pewter face into an exaggerated scowl. “Don’t be such a philistine. Once the artist decides the parameters, they’re sacrosanct —”
“Hashim’s parameters are just incomprehensible. Look, I know I won’t like it. You go.”
Inoshiro hesitated, slowly letting vis features shrink back to normal size. “You could appreciate Hashim’s work, if you wanted to. If you ran the right outlook.”
Yatima stared at ver. “Is that what you do?”
“Yes.” Inoshiro stretched out vis hand, and a flower sprouted from the palm, a green-and-violet orchid which emitted an Ashton-Laval library address. “I didn’t tell you before, because you might have told Blanca ... and then it would have got back to one of my parents. And you know what they’re like.”
Yatima shrugged. “You’re a citizen, it’s none of their business.”
Inoshiro rolled vis eyes and gave ver vis best martyred look. Yatima doubted that ve’d ever understand families: there was nothing any of Inoshiro’s relatives could do to punish ver for using the outlook, let alone actually stop ver. All reproving messages could be filtered out; all family gatherings that turned into haranguing sessions could be instantly deserted. Yet Blanca’s parents — three of them Inoshiro’s — had badgered ver into breaking up with Gabriel (if only temporarily); the prospect of exogamy with Carter-Zimmerman was apparently beyond the pale. Now that they were together again, Blanca (for some reason) had to avoid Inoshiro as well as the rest of the family — and presumably Inoshiro no longer feared that vis part-sibling would blab.
Yatima was a little wounded. “I wouldn’t have told Blanca, if you’d asked me not to.”
“Yeah, yeah. Do you think I don’t remember? Ve practically adopted you.”
“Only when I was in the womb!” Yatima still liked Blanca very much, but they didn’t even see each other all that often, now.
Inoshiro sighed. “Okay: I’m sorry I didn’t tell you sooner. Now are you going to come see the piece?”
Yatima sniffed the flower again, warily. The Ashton-Laval address smelt distinctly foreign ... but that was just unfamiliarity. Ve had vis exoself take a copy of the outlook and scrutinize it carefully.
Yatima knew that Radiya, and most other miners, used outlooks to keep themselves focused on their work, gigatau after gigatau. Any citizen with a mind broadly modeled on a flesher’s was vulnerable to drift: the decay over time of even the most cherished goals and values. Flexibility was an essential part of the flesher legacy, but after a dozen computational equivalents of the pre-Introdus lifespan, even the most robust personality was liable to unwind into an entropic mess. None of the polises’ founders had chosen to build predetermined stabilizing mechanisms into their basic designs, though, lest the entire species ossify into tribes of self-perpetuating monomaniacs, parasitized by a handful of memes. It was judged far safer for
each citizen to be free to choose from a wide variety of outlooks: software that could run inside your exoself and reinforce the qualities you valued most, if and when you felt the need for such an anchor. The possibilities for short-term cross-cultural experimentation were almost incidental.
Each outlook offered a slightly different package of values and aesthetics, often built up from the ancestral reasons-to-be-cheerful that still lingered to some degree in most citizens’ minds: Regularities and periodicities — rhythms like days and seasons. Harmonies and elaborations, in sounds and images, and in ideas. Novelty. Reminiscence and anticipation. Gossip, companionship, empathy, compassion. Solitude and silence. There was a continuum which stretched all the way from trivial aesthetic preferences to emotional associations to the cornerstones of morality and identity.
Yatima had vis exoself’s analysis of the outlook appear in the scape in front of ver as a pair of before-and-after maps of vis own most affected neural structures. The maps were like nets, with spheres at every junction to represent symbols; proportionate changes in the symbols’ size showed how the outlook would tweak them.
“‘Death’ gets a tenfold boost? Spare me.”
“Only because it’s so underdeveloped initially.”
Yatima shot ver a poisonous look, then rendered the maps private, and stood examining them with an air of intense concentration.
“Make up your mind; it’s starting soon.”
“You mean make my mind Hashim’s?”
“Hashim doesn’t use an outlook.”
“So it’s all down to raw artistic talent? Isn’t that what they all say?”
“Just... make a decision.”
Vis exoself’s verdict on the potential for parasitism was fairly sanguine, though there could be no guarantees. If ve ran the outlook for a few kilotau, ve ought to be able to stop.
Yatima made a matching flower grow from vis own palm. “Why do you keep talking me into these crazy stunts?”
Inoshiro’s face formed the pure gestalt sign for unappreciated benefactor. “If I don’t save you from the Mines, who will?”
Yatima ran the outlook. At once, certain features of the scape seized vis attention: a thin streak of cloud in the blue sky, a cluster of distant trees, the wind rippling through the grass nearby. It was like switching from one gestalt color map to another, and seeing some objects leap out because they’d changed more than the rest. After a moment the effect died down, but Yatima still felt distinctly modified; the equilibrium had shifted in the tug-of-war between all the symbols in vis mind, and the ordinary buzz of consciousness had a slightly different tone to it.
“Are you okay?” Inoshiro actually looked concerned, and Yatima felt a rare, raw surge of affection for ver. Inoshiro always wanted to show ver what ve’d found in vis endless fossicking through the Coalition’s possibilities — because ve really did want ver to know what the choices were.
“I’m still myself. I think.”
“Pity.” Inoshiro sent the address, and they jumped into Hashim’s artwork together.
Their icons vanished; they were pure observers. Yatima found verself gazing at a red-tinged cluster of pulsing organic parts, a translucent confusion of fluids and tissue. Sections divided, dissolved, re-organized. It looked like a flesher embryo — though not quite a realist portrait. The imaging technique kept changing, revealing different structures: Yatima saw hints of delicate limbs and organs caught in slices of transmitted light; a stark silhouette of bones in an X-ray flash; the finely branched network of the nervous system bursting into view as a filigreed shadow, shrinking from myelin to lipids to a scatter of vesicled neurotransmitters against a radio-frequency MRI chirp.
There were two bodies, now. Twins? One was larger, though — sometimes much larger. The two kept changing places, twisting around each other, shrinking or growing in stroboscopic leaps while the wavelengths of the image stuttered across the spectrum.
One flesher child was turning into a creature of glass, nerves and blood vessels vitrifying into optical fibers. A sudden, startling white-light image showed living, breathing Siamese twins, impossibly transected to expose raw pink-and-gray muscles working side-by-side with shape-memory alloys and piezoelectric actuators, flesher and gleisner anatomies interpenetrating. The scene spun and morphed into a lone robot child in a flesher’s womb; spun again to show a luminous map of a citizen’s mind embedded in the same woman’s brain; zoomed out to place her, curled, in a cocoon of optical and electronic cables. Then a swarm of nanomachines burst through her skin, and everything scattered into a cloud of gray dust.
Two flesher children walked side-by-side, hand-in-hand. Or father and son, gleisner and flesher, citizen and gleisner ... Yatima gave up trying to pin them down, and let the impressions flow through ver. The two figures strode calmly along a city’s main street, while towers rose and crumbled around them, jungle and desert advanced and retreated.
The artwork, unbidden, sent Yatima’s viewpoint wheeling around the figures. Ve saw them exchanging glances, touches, kisses — and blows, awkwardly, their right arms fused at the wrists. Making peace and melting together. The smaller lifting the larger onto vis shoulders — then the passenger’s height flowing down to the bearer like an hourglass’s sand.
They were parent and child, siblings, friends, lovers, species, and Yatima exulted in their companionship. Hashim’s piece was a distillation of the idea of friendship, within and across all borders. And whether it was all down to the outlook or not, Yatima was glad to be witnessing it, taking some part of it inside verself before every image dissolved into nothing but a flicker of entropy in Ashton-Laval’s coolant flow.
The scape began moving Yatima’s viewpoint away from the pair. For a few tau ve went along with this, but the whole city had decayed into a flat, fissured desert, so apart from the retreating figures there was nothing to be seen. Ve jumped back to them — only to find that ve had to keep advancing vis coordinates just to stay in place. It was a strange experience: Yatima possessed no sense of touch, or balance, or proprioception — the Konishi design eschewed such delusions of corporeality — but the scape’s attempt to “push” ver away, and the need to accelerate against it, seemed so close to a physical struggle that ve could almost believe ve’d been embodied.
The figure facing Yatima aged suddenly, cheeks hollowing, eyes filming over. Yatima moved around to try to see the other’s face — and the scape sent ver flying across the desert, this time in the opposite direction. Ve fought vis way back to the ... mother and daughter, then decaying robot and gleaming new one ... and though the two remained locked together, hand-in-hand, Yatima could all but feel the force trying to tear them apart.
Ve watched flesh hand gripping skin-and-bones, metal gripping flesh, ceramic gripping metal. All of them slowly slipping. Yatima looked into the eyes of each figure; while everything else flowed and changed, their gazes remained locked together.
The scape split in two, the ground opened up, the sky divided. The figures were parted. Yatima was flung away from them, back into the desert — with a force, now, that ve could not oppose. Ve saw them in the distance — twins again, of uncertain species, reaching out desperately across the empty space growing between them. Arms outstretched, fingertips almost brushing.
Then the halves of the world rushed apart. Someone bellowed with rage and grief.
The scape decayed into blackness before Yatima understood that the cry had been vis own.
The forum with the flying-pig fountain had been abandoned long ago, but Yatima had planted a copy from the archives in vis homescape, the cloistered square marooned in the middle of a vast expanse of parched scrubland. Empty, it looked at once too large and too small. A few hundred delta away, a copy (not to scale) of the asteroid ve’d watched being trimmed was buried in the ground. At one point Yatima had envisioned a vast trail of similar mementos stretching across the savanna, a map ve could fly over whenever ve wanted to review the turning points in vis life ... but then the whole id
ea had begun to seem childish. If the things ve’d seen had changed ver, they’d changed ver; there was no need to re-create them as monuments. Ve’d kept the forum because ve genuinely liked to visit it — and the asteroid out of the sheer perverse pleasure of resisting the urge to tidy it away.
Yatima stood by the fountain for a while, watching its silver liquid effortlessly mock the physics it half-obeyed. Then ve re-created the octahedral diamond, the six-pointed net from vis lesson with Radiya, beside it. That physics meant nothing in the polises had always been clear to ver, as it was to most citizens; Gabriel disagreed, of course, but that was just Carter-Zimmerman doctrine talking. The fountain could ignore the laws of fluid dynamics just as easily as it could conform to them. Everything it did was simply arbitrary; even the perfect gravitational parabola of the start of each stream, before the piglets were formed, was nothing but an aesthetic choice — and the aesthetic itself was nothing but the vestigial influence of flesher ancestry.
The diamond net was different, though. Yatima played with the object, deforming it wildly, stretching and twisting it beyond recognition. It was infinitely malleable ... and yet a few tiny constraints on the changes ve could make to it rendered it, in a sense, unchangeable. However much ve distorted its shape, however many extra dimensions ve invoked, this net would never lie flat. Ve could replace it with something else entirely — such as a net which wrapped a torus — and then lay that new net flat ... but that would have been as meaningless as creating a non-sentient, Inoshiro-shaped object, dragging it into the Truth Mines, and then claiming that ve’d succeeded in persuading vis real friend to come along.