Learning the World

4 — A Moving Point of Light

Third Finger Street was the axis of nightlife in Five Ravines. Stumblefruit groves and laughterburn grottoes lined it. Trudge-drawn cabs jostled motor vehicles in its metalled way; unsteady walkers thronged the pavements. Cable seats whizzed overhead, carrying the elderly or pregnant above this louche promenade, and those already too intoxicated to safely fly away from it. To look up was to risk a headache-inducing fireworks display of proximity-sense overload. To fly above it was to risk worse, and plenty did. Flitters, small and deft, dodged between the lumbering flights of humans.

Darvin and Kwarive walked along the pavement, heading for the Bard’s Bad Behaviour, a popular copse. Kwarive, as usual, teased Darvin about his refusal to take a cab. “Too tightfisted for a fare,” she said. “You don’t know how to impress a lady.”

“It isn’t that,” Darvin said. “I think it’s cruel.”

“Now you’re just being sentimental.”

It was a joke between them. Darvin was tiring of it. Needled, he needled back.

“And I wouldn’t be if I cut up animals?”

“Instead of looking at stars? Sure you wouldn’t.”

“I eat prey,” he pointed out.

“Oh, that,” said Kwarive. “Everybody eats prey. It’s dissection that makes you understand.”

Darvin resisted the urge to quibble that not everyone ate prey; he intuited that calling mystics from the South to the witness perch would not help his case.

“Understand what!” he asked. “That the beasts have bones like ours, blood like ours, nerves like ours, and who is to say they don’t have feelings like ours? Doesn’t a flitter squeal when you flay it?”

Dissecting flitters was a cheap and moral way of learning human anatomy, he had gathered.

“We kill or anaesthetise them first,” Kwarive said.

“Ah-hah!” said Darvin. “So you admit they feel pain? That not anaesthetising them would be inhumane?”

“No,” said Kwarive. “It would be difficult, because they would struggle and might bite, and their physiology would be that of an animal in pain. Which is not what we want to examine.”

“So most of what we know of physiology is based on that of drugged animals? Interesting.”

“You have a point there,” Kwarive said. “But what I’ve learned from dissections and other studies is that humans really are different from other animals. Brain size, speech, self-awareness, use of tools…”

“Trudges use tools,” Darvin said, “and they can speak. That’s why what we do to them is cruel, and that’s why I won’t—”

“ — take a cab?” Kwarive snorted. “You make my point for me. Trudges can be trained to hammer or hoe, but they don’t invent—”

“Oh, it’s inventing now?”

“ — don’t invent new uses, and they can utter a few simple phrases and understand a few dozen more, but they don’t converse. They don’t even use human speech to talk amongst themselves. They use their own grunts and cries. What they have is signals, not speech.”

“A fine distinction!”

“One that makes all the difference in the world,” said Kwarive.

They had stopped at a crossroads. Traffic was tangled up; a street warden swooped and circled overhead, screaming imprecations and instructions at drivers and trudges. Darvin glanced sidelong at Kwarive. Her face was stern and earnest. This was not their usual banter.

“All right,” he said. He jutted his chin at a brace of cab-hauling trudges who stood panting at the junction. Their hands clutched the T-bar of the cab’s yoke; their feet, claws trimmed, were shod in thick rubber; their wings, the webs slashed in kithood from joint to trailing edge, hung atrophied and useless at their sides. Their arms and legs seemed by human standards grossly overmuscled, with tendons like cables. Their jaws champed leaf and their lips dribbled saliva. Their eyes, glazed by the drug, rolled, their gaze darting hither and thither. Behind them and the driver, in the two-seater cab, a couple held hands and giggled over a smouldering bunch of laughterburn. With one wing the boy enfolded and hooded the girl, with the other he wafted the smoke into the tent thus created. The driver, perched in front of the cab, paid this unseemly display no attention.

“Do you think,” said Darvin, “that the trudges really don’t suffer? That they don’t miss using their wings?”

“They wouldn’t be trudges if they could fly.”

There was something maddening in the unassailable logic of this missed point.

“Forget flying, there’s enfolding to consider too.” Kwarive shrugged. “Doesn’t seem to stop them pairing and breeding.”

“Those we don’t geld or spay, at any rate.”

“Exactly. So I don’t think they miss their wings.”

The traffic became unsnarled. The warden swooped, and hooted an order. The cabdriver flicked his whip across the shoulders of the two trudges. They trotted off. “See?” said Kwarive. “They didn’t even wince.”

“It was the leaf,” said Darvin, plodding across the road.

“No,” said Kwarive. “They are less sensitive to pain than we are. Their skin is thicker, and has fewer nerve endings.”

“How do you know that?”

She looked at him. “Dissection.”

At the Bard’s Bad Behaviour every tree branch and other perch was crowded. Electric lights blazed from cables strung across the treetops. Pulleys drew cables bearing fruit-laden or empty baskets. Darvin squelched across a floor littered with discarded stumblefruit rinds and laughterburn ash to the stall and bought a double wingful of fruit. Kwarive joined him halfway back and relieved him of half the burden. As they gazed around and up looking for a perch or for anyone they knew, a cry came from above. “Up here!” shouted Orro.

“Not likely!” Darvin yelled back. “We’re loaded! Come on down!”

Grumbled assent was followed by Orro’s arrival, crashing and swinging one-handed, a half-used fruit in his free hand. He dropped in front of them and straightened, swaying. His white chest fur was yellow and sticky-looking with juice. He slapped Darvin’s shoulder and, with the exaggerated gallantry of the drunk, touched his nose to the crook of Kwarive’s wing.

“To the wall!” he said. “Only perch left in this dive.” The three made their way through the crowd and hopped up onto one of the few remaining available spaces on the top of the wall around the grove. By unspoken agreement, Darvin and Kwarive let the unsteady Orro sit between them. Sitting cross-legged, they could hold the fruits in their laps, freeing their folded wings for balancing and their hands for holding. Darvin passed a fresh fruit to Orro, lifted his own with both hands, and bit in. He spat away the first chunk of rind and tipped the fruit to let the first flow of fermented juice flood into his mouth. His belly warmed and the world became more cheerful. Orro scooped the last of the pulp from his almost empty fruit, stuffed it in his mouth, and threw away the husk. With hardly a pause to chew and swallow he tore into the new fruit.

“Hmm,” he said, juices trickling down his chin, “good. Thanks, Darvin. You’re a pal, you are. And a colleague.”

“Think nothing of it,” said Darvin, hoping Kwarive, to whom he’d praised Orro’s genius many times, wasn’t utterly disillusioned by the physicist’s unwonted excess. He looked at her over the back of Orro’s hunched shoulders and waggled his ears and rolled his eyes. She grinned back.

“Didn’t expect to find you so, ah…”

“Drunk?” Orro guffawed and sat up straighter. “Not drunk. Seriously. Just badly behaved. Place for it, yes?”

“I suppose so,” said Darvin.

“I have a reason,” said Orro, staring up into the night sky. The two moons hung like curved blades. The priests of the cults would be scrying the angles and sharpening their sickles for the bilunar sacrifices of green herbs to the blue-green Queen.

“You always have a reason for doing things,” said Darvin. “So what is it?”

“Take your little student here,” said Orro.

“Ye-es,” said Darvin, no longer relaxed. The word came out like a half-drawn blade.

“Nothing to worry about, has she? Have you, young lady?”

“Nothing you need know about,” said Kwarive.

“Ah. Indeed. No offence meant. Still. For a student, life is simple. Study. Make love. Eat and drink. Learn. And what you learn, Kwarive, you and your cohorts, is what is known.”

“We learn what is known,” said Kwarive. “Now, there’s a surprise.”

“What I said is not empty,” said Orro. “Unlike this fruit.”

He cast away the rind. Darvin passed him another drink.

“Thanks,” Orro mumbled, munching in. “Hmm. Right. Now, for us scientists, on the other wing, life is not quite so simple. Because we learn the unknown. Unlike, hah-hah, our esteemed friends the philosophers, who learn the unknowable.” He waved skyward, almost losing his balance. “The great flapping unknowable, like the wings of God.”

There had been a charming legend that night was the result of the Sun’s enfolding Ground with His wing. So charming was it that even today a disrespectful allusion to it could cause offence. Of all the sciences, astronomy was the one the superstitious liked least.

“Leave the unknowable alone,” said Darvin.

“Sound advice. Well, my friends, imagine my discomfiture to discover, this very day, that by investigating the unknown I had diminished the known. That, in short, I did not know all I had thought I knew. That, to make it even shorter, I did not know how to calculate correctly. That I do not. That I can’t count. I am pitiable.”

“Don’t be silly,” said Kwarive. “Everybody makes mistakes.”

“I do not make mistakes,’ said Orro. “Not in arithmetic. Not in measurement. Not in calculation.”

“Did you use a calculating machine?” asked Darvin.

“Of course,” said Orro.

“There you are,” said Darvin. “A bug. They’re everywhere this time of year.”

Orro looked at him morosely. “I thought of that. I sprayed insecticide. I cleaned the gears. I oiled. I ran test calculations. All was well. And when I turned to my own calculations, I could not make them come out right.”

“What were they?” asked Kwarive.

“Ah!” said Orro. “That is where your friend and my colleague here drops into the clearing, so to speak. I was trying to calculate the orbit of his comet.”

Darvin felt a rush of relief as potent as the first spurt from a stumblefruit.

“That’s all right,” he said. “You’re a physicist, not an astronomer. There are always disturbances in the paths of comets. You can’t expect some perfect trajectory, you know.”

“I know that,” said Orro. He had dropped his husk, and not so much as hinted at wanting another fruit. Agitated, he began licking his hands and the juice-matted fur of his arms. “I do not expect a perfect trajectory. But nor do I expect to find every equation I try for the path disproven by the next night’s plates.”

He stopped, stared upward again for a moment, then sighed and reached a hand sideways. Without demur, Darvin passed him the last fruit in his lap.

“So that’s why you find me here,” said Orro. “Badly behaved, in the Bard’s Bad Behaviour. Trying to jolt my brain loose from whatever stupid misconception is giving me this stupid anomaly in my results.”

“What anomaly?” asked Darvin.

“A comet slowing down,” said Orro.

They took him home.

The following morning, Darvin sat in his office and waited for the chewed leaf and the tea to dispel his stumblefruit headache, and mulled over a deeper unease. He hadn’t given the comet much thought in the weeks since its discovery, having persisted in the quest for the unknown outer planet, and he’d assumed that Orro was concentrating likewise on his own major research. The photographs from the wind-tube kinematography had provided a plausible intuitive basis for a rigorous mathematical account of wing-flapping flight. Orro had talked about little else for days after the film had been processed. It was disquieting to discover that he was wasting time and passion in hunting down what he himself had called a stupid anomaly. It was unworthy of the man.

Darvin sighed. Perhaps not. The very rigour that made Orro’s work so promising was doubtless the reason why he couldn’t let this problem go unsolved. Darvin berated himself for letting Orro investigate the comet’s orbit in the first place, without giving him any help or advice. No doubt some assumption or premise, second nature to an experienced astronomer, had been overlooked by the physicist.

He stood up and dived out of the window and flew to the Physics Building. There was no response when he knocked on Orro’s office door, not to his surprise. He tested the door, found it unlocked, and let himself in.

At first glance the place looked reassuring: long strips of film tacked to the walls, showing moment-by-moment frames of himself in flight; a complex, incomplete model of a chiropter, the fine paper of its wings still undoped; sheets of scribbled reckoning on the tables. A second look revealed that these sheets had been brushed aside, and a space cleared for a rack of Darvin’s night-sky images, in between an electric lamp and an apparatus of mounted lenses: he guessed it was Orro’s jury-rigged approximation to a blink comparator. Beside these devices lay a current ephemeris and a closed notebook bound in black grazer leather. Darvin opened it, and found page upon page of crabbed, jagged Gevorkian script. Equations and formulae, arithmetic, results from… ah yes, there was the calculating machine, behind the swivel perch on which Orro would have sat.

Darvin sat down himself, the heels of his hands against his temples, and began to work his way through the notebook, trying to see where his colleague had gone astray. Every so often he turned to the calculating machine. Within an hour he was doing this so often that it clattered and rang like the till in a busy shop. Then it fell silent, and Darvin gazed in gloomy triumph at the notes.

He didn’t hear Orro arrive. A short noonday shadow fell across the page, and he looked up.

“I’ve found your problem,” Darvin said.

“You have?” said Orro. “Then I forgive the intrusion.”

Darvin jumped up and clapped Orro’s shoulder. Orro winced and put a hand to his head.

“Sorry,” said Darvin, pacing across the floor, and turning to pace back. “It’s very simple. You’ve assumed that the comet is outside the orbit of the Warrior.”

Orro shook his head, then clutched it again. “I haven’t assumed it. It is outside. Not far, but definitely outside.”

“It can’t be,” said Darvin. “That’s still too far away from the Sun for a comet to be visible, let alone as bright as it is.”

“Does the anomaly disappear when you recalculate on the other assumption?”

“I haven’t got that far,” Darvin admitted.

“I thought not,” said Orro. “In any case, you needn’t bother. That was where I started.” He reached for a shelf above the table, and pulled down another notebook. “Check that one too if you want. I found the anomaly, and then I realised it couldn’t be right, because the comet’s path is not perturbed by the gravitation of the Warrior, or of the Queen. My calculations on the assumption that it was much farther out — the ones you’ve been looking at — are my second attempt. And the anomaly of apparent deceleration is still there. Not only that, but you’ve just pointed out another one, the comet’s visibility and brightness. I tell you, it’s enough to drive a physicist to drink.”

Darvin laughed. “I underestimated you,” he said. “I thought you were missing something that would be obvious to an astronomer. You weren’t. This is good solid reckoning, Orro.”

“Very well,” said Orro. He looked relieved. He sat on the perch and caught the table edge with his toe-claws and leaned back. “Let’s spit the rind and chew the pith.” He closed his eyes for a moment, with a faint shudder. “Metaphorically. We have an anomalously bright celestial object, anomalously distant, anomalously decelerating. It is traversing the region of the Queen of Heaven’s Daughters, the green stars. What hypothesis springs to mind?”

“None,” said Darvin. “No celestial object decelerates on its way in towards the Sun.”

“No natural celestial object. Very well then. It must be an unnatural object, or rather, an artificial one.”

Darvin laughed. “An alien spaceship?”

Orro shrugged. “Call it that if you must. It may be something not conceived of even in engineering tales.” He pointed over his shoulder at the calculating machine. “I’ve sometimes speculated on what could be achieved by such a machine, given a few eights-of-eights of years of progress in the art… but leave that aside.”

“Yes, I should think aliens are quite enough to be going on with, leaving aside mechanical thinkers.” Darvin punched his friend’s shoulder. “Come on! This is quite unscientific! It’s always better to seek the simpler explanation.”

“You have one?”

“The glimmerings of one,” said Darvin. “Just as speculative as yours, I admit, but requiring fewer… supplementary hypotheses.”

“Give us it then.”

Darvin paced back and forth a few times before replying. In truth he was not as sceptical of aliens as he had sounded. The possibility was an old and respectable one in the astronomy of Seloh and Gevork; even in religion, the green tinge of the Queen had been associated with life, and the spectroscopy confirmed that. There had even been a delightful legend that the Queen of Heaven’s Daughters had been given life by the Queen, and while astronomers discounted that, they allowed that the green tinge of the Daughter stars might indicate the presence of life on any planets around them, while admitting they had no idea how such hypothetical life-bearing planets could filter the light from their suns. There was one outlandish, but established, suggestion that some kind of green plant could grow in space itself, perhaps from the surfaces of comets, but the difficulties of this idea were as obvious as the absence of imaginable alternatives to it.

“Suppose what we have here,” he said, “is a natural object, but one unknown to astronomy. A new kind of comet. We know that a comet’s tail consists of gas glowing in the Sun’s rays.”

“Yes,” said Orro.

“Now, the gas is given off as the comet warms up, on approaching the Sun. Now if, if there were a kind of comet or similar body that began to outgas much farther out from the sun, the flow of gases would — if aligned towards the Sun — slow down the comet and make it brighter than it would otherwise appear.”

Orro closed his eyes and tilted his head back. His lips moved. “That might just work,” he said at last. “It would require some damned ticklish and unlikely coincidences: mass, orientation, specific impulse… am I right in thinking that cometary outgassings don’t normally have any effect on their orbit?”

“You are,” said Darvin. “This would have to be, as you say, something quite different from outgassings as we understand them. The gases propelled outward by radioactive heating within, perhaps?”

“Radioactivity is a remarkably faint source of power,” said Orro. “Certainly in any concentrations found in nature, though there have been some experiments and calculations… all very speculative stuff, of course.”

Darvin had never heard of work along these lines. “In Gevork?”

Orro opened his eyes and stared at him; it seemed, through him. “Speculation.” It wasn’t clear to just what Orro applied the epithet. He waved a hand. “Ignore that. We can only describe what we incontestably have evidence for. So let us describe it.”

“How?”

Orro jumped off the perch, strode forward, and clasped Darvin’s hand. “A joint note to the journals? Or failing that, the physics wire? Does not ‘A Distant, Decelerating Celestial Object: Some Observations,’ by Darvin and Orro, of Five Ravines, have a certain ring to it?”

“It does,” said Darvin. He returned the handshake. “If only I didn’t suspect that we’ve both made some ghastly mistake, which some undergraduate will spot straight away, in which case it’s a title that’ll ring in our ears for the rest of our lives.”

They finished checking the calculations that evening. By midnight they had written the paper. It was brief, detailed, mostly mathematical, and included no speculation whatever about the nature of the decelerating object.

“You know,” Darvin said, glancing it over one last time, “I can’t help thinking this looks a bit trashy and sensational.”

Orro didn’t laugh. “When I close my eyes, I see its title as a screaming headline in large black type.”

“That’s fatigue,” said Darvin. He helped himself to some tea. “But yes, I do worry about the effect on public opinion. In engineering tales, the arrival of aliens is invariably followed by mass panic.”

“That’s fanciful,” said Orro. “It has never been tested.”

“Well, in the nature of things, no,” said Darvin. “However, there was one incident back in the Dawn Age, when the first observations of signs of life on the Queen were published. That led to, if I recall my history books, a stock market bubble, a subsequent collapse, and a brief frenzy of religious persecution.”

“That was the Dawn Age,” said Orro. “We are now in the Day.”

“So we like to believe. A day in which dirigibles almost too high to see patrol our skies above the Broad Channel. When the Broad Channel itself is patrolled by warships from both shores. A day in which war with Gevork is openly spoken of, and not just in engineering tales.”

“And a day in which many such as you and I cooperate like civilised men.”

“That’s true,” said Darvin. “Perhaps a new kind of comet — even if it was thought to be an alien spaceship — would result in wonder rather than fear.”

“How long,” Orro mused, “before amateurs with telescopes notice it?”

“Several eights of eight-days, even with the best private telescopes, I should imagine.”

“So there is no risk, really, of our discovery’s being preempted. We could hold back for a little while—”

“I said ‘private,’ ” said Darvin. “I’m not willing to see Seloh’s Reach being beaten by Gevork on this discovery. Or by any other country.”

“Nor me,” said Orro. He gave Darvin a troubled look. “Surely you don’t think I—”

“Oh, no, not at all,” said Darvin. “But some of your — their astronomers may already have noticed the anomaly.”

“I doubt it,” said Orro. “Gevorkian astronomy is focused, you might say, on the stars. Even the planets, leave alone comets, are regarded as almost beneath the notice of serious scientists.”

“The other realms—”

“Astrologers!”

“That’s the problem,” said Darvin. “The sky-watchers of the Court of the Southern Rule pay a great deal of attention to comets as portents — their priorities are rather the reverse of your Gevorkians’. And their telescopes — say what you like about the beliefs and motives of their builders — are of the highest craft. They were producing detailed sky maps before our Dawn Age — we have one in the university’s museum. I should take another look at it, to see if it shows any earlier comets in the Daughters region. It might suggest how the sky-watchers would interpret this one.”

“Well,” said Orro, with a shrug, “I doubt that we need worry about their panicking the populace. Or preceding us into print, for that matter.”

Darvin was not so sure about that. “Some of their younger sky-watchers are talented and educated men, and they do have their own version of a popular press,” he pointed out. “They invented it, after all.”

Orro wiped a hand across his tired eyes. “There’s one more thing we can do,” he said. “That is, to project the path of the… object, check it against your latest plates, and work out exactly when it will become visible to amateur astronomers, and indeed to the naked eye.”

“The naked eye!” Darvin had all along assumed that the comet that now bore his name would one day be visible to everyone, but the thought now brought him up short. Since confirming Orro’s calculations he’d begun to think of it almost as a secret.

“Why not?” said Orro. “A year or so from now, I’d guess. Let’s check it.”

’Tomorrow,” said Darvin.

In the morning a low fog from the sea overlay Five Ravines. Darvin had to rely more than usual on his proximity sense as he flew to the university. The world was a grey haze interrupted by red flashes. On one sideways turn he noticed how the fog curled away from his wing tip, and reflected on how something like fog — smoke? steam? — might be used in Orro’s wind-tube experiments.

But there were to be no such experiments that day. When he’d stepped along the hall, shaking drops of moisture from his fur, Darvin found Orro hanging asleep from the ceiling outside his door. Darvin tapped his wing joint. The other man shuddered, unfolded his wings, and blinked up. Inside his wings, he’d been clutching a satchel.

“Have you been here all night?” Darvin asked.

“No,” said Orro. “Not long. But I needed the sleep.”

He bent upward, caught the wooden slats of the ceiling with his hands, let go with his feet, and dropped upright and caught the satchel before it reached the ground. Scratching himself, he followed Darvin into the office. It took them an hour or so to work through Orro’s calculations and find where to look for the comet on the more recent plates, those from the past couple of eight-days. Darvin set up the pair of plates, adjusted the blink comparator, and found the comet, brighter than before. Orro noted the degrees of displacement along the vertical and horizontal axes, scribbled in his notebook, and nodded. “On target,” he said.

They repeated this for nine pairs of plates. The comet’s path was exactly as Orro’s calculation predicted.

On the tenth pair, there was no jump. Instead, the comet seemed to flash on and off in the same position. On closer examination, Darvin found that it was present on the earlier plate, but not on the later. On the eleventh pair, and all subsequent pairs, it was altogether gone.