by Larry Niven
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For our neighbor, Ron Lauber, who is kind to cripples
—MATTHEW JOSEPH HARRINGTON
For my brother Michael, for half a century of kindness
—LARRY NIVEN
CONTENTS
Title Page
Copyright Notice
Dedication
Epigraph
Epigraph
Prologue
Part I
Part II
Part III
Part IV
Part V
Part VI
Part VII
Part VIII
Part IX
Part X
Part XI
Part XII
Part XIII
Part XIV
Part XV
Part XVI
Part XVII
Part XVIII
Part XIX
Part XX
Part XXI
Part XXII
Part XXIII
Part XXIV
Part XXV
Part XXVI
Part XXVII
Part XXVIII
Part XXIX
Part XXX
Part XXXI
Part XXXII
Part XXXIII
Part XXXIV
Part XXXV
Part XXXVI
Part XXXVII
Cast and Crew
Tor Books by Larry Niven
About the Authors
Copyright
Prudence is the belief that bad things have preventable causes.
Paranoia is the belief that it’s all the same cause.
Politics is the belief that you know what the cause is.
I would sooner believe two Harvard professors would lie than that stones may fall from Heaven.
—FALSELY ATTRIBUTED TO THOMAS JEFFERSON
Ignorance is preferable to error; and he is less remote from the truth who believes nothing, than he who believes what is wrong.
—THOMAS JEFFERSON
Look! Up in the sky!
—JERRY SIEGEL
PROLOGUE
Out of the night that covers me,
Black as the Pit from pole to pole.
—WILLIAM ERNEST HENLEY, “INVICTUS”
CIRCA 5 BILLION BC
A protosun had formed but not yet ignited, and planets had already formed in orbit around it. Some of the lesser bodies were in orbits that still had considerable eccentricity. One of these struck a glancing blow to the third planet, whose materials had barely had time to separate into layers. It was almost half the diameter of the third planet, and tore away more than half the crust and a good deal of mantle. The impacting body burst, and scattered as it moved on, but much of the planet’s debris ended up moving slowly enough to remain in orbit. A good deal fell back in. What remained in orbit was a bit over one percent of the total mass of the planet. It accreted into a ball, and would eventually have fallen back from friction with ambient material had the protosun not ignited scant millions of years later, blowing away the gas cloud from the inner system. The wounded planet had enough gravity to pick up what eventually became an atmosphere and oceans as the gases moved out from the Sun. Planets farther out collected considerably more, as it was moving more slowly and they were more massive than the inner planets.
The Moon was too light to retain much of anything, except at the poles, where there was shade.
It might be considered absurd to think of rocks plotting revenge, but pieces of the impact debris kept showing up to take another shot at the planet.
Some examples were really memorable.
CIRCA 250 MILLION BC
Earth had one supercontinent that wrapped halfway around the planet. Pangaea was formed from the wreckage of previous supercontinents, which were fully as large and stable. Their respective breakups would have been inexplicable if not for one factor.
A smallish cluster of rocks that had wandered out past the orbit of the ninth planet had accumulated a good deal of ice and formed a body enormously larger. Witnesses, had any evolved yet, would call the result a comet … right up until the time they started to get hysterical.
Pangaea was shaped in a ragged arc. The comet had broken up into chunks. They struck like a shotgun blast over a region not far from the middle of the outside of the curve, driving shock waves through the planet. These converged on the other side of the planet, at the far end of the arc, producing vulcanism that lasted more than a hundred thousand years. The supercontinent was already visibly breaking up by the time it died down.
More than 96 percent of all species on the planet were extinct by the time the smoke cleared. Those that had not perished in the shock wave traveling over the land had either died from the increased temperatures—dust and soot from the impact had covered the world, absorbing more sunlight—or had suffocated in the changed atmosphere. A kind of insect did very well out of the deal: it ate corpses. As the corpse supply dwindled, variants found other things to eat. These creatures later became known as beetles.
Among larger animals, reptiles took over from amphibians, the latter being less tolerant of higher temperatures—but, compared to the total mass of beetles on the assorted new continents, the dinosaurs didn’t amount to much.
CIRCA 65 MILLION BC
A chunk of stone and metal, no more than a few miles across, struck the atmosphere near one end of one of the two great pole-to-pole oceans. It took less than a minute to reach the ocean, but that was long enough for the air in its path to be compressed into what amounted to an incandescent wall, and for the asteroid’s structure to be heated and softened itself by the compression. When the mass of air struck the water there was a steam explosion, perhaps a hundred times the size of the volcanic one that would later end Minoan civilization and cause a change of dynasty in every culture on earth in 1435 BC. The collapse and explosion of the island of Thera would have disappeared unnoticed in this blast.
Megatons of water boiled away as the plasma wave descended through the ocean, and rock peeled from the projectile in the backblast. Metal too liquefied, but cohered, and when that struck the ocean floor it bored through it like a shaped charge through mud—which was more or less exactly what was happening. Liquid iron, with admixtures of other metals, drilled through the planet’s crust and into the mantle … whose normal temperature was high enough to make bronze flow like syrup.
There was a pretty good vacuum behind the projectile, since air had been compressed in front of it too fast to move in behind it. Water hammered in.
The steam explosion made the impact blast look sickly. The metal of the asteroid was spread over the entire planet in aerosol form. Live steam held a crater open in the ocean, the force of its boiling exceeding the pressure of the water for days. As the steam rose and spread, high in the atmosphere, it cooled and formed clouds that completely covered the planet for three years.
The dinosaurs had had their shot. Reptiles could deal with heat. An Ice Age, not so much.
Water kept boiling as magma flowed out of the mantle. The magma slowed as it was cooled by the infalling ocean, but it never did stop completely, and natural steam vents still
run through the land that formed there, despite the fact that where there are no vents the land is frozen solid. The first humans to reach it saw this and named it Iceland.
JULY 2005 AD
A small boy, due to start second grade in a few weeks, watched a pretty good simulation a friend’s father had put together for a short film contest. The entry subsequently lost because it didn’t conform to the Official Consensus on where the Dinosaur Killer had struck, and its maker concluded that it had been a waste of time.
Toby Glyer had nightmares for almost a month. Then he decided somebody better do something.
NOVEMBER 2051 AD
The population of the Solar System was roughly forty billion sentient creatures.
Possibly a quarter of these were human beings, all of whom lived on Earth.
The rest lived on a much smaller planet—about four kilometers across—and had never been to Earth.
But they were going there.
It was time to pay some bills.
Just now it was also time for a course adjustment. Everyone found something firm to hang on to, and the drive was turned on. It was hot enough that it didn’t produce light visible to humans until it had expanded and cooled.
* * *
The biggest international attraction of the Republic of Puerto Rico was the rebuilt and redesigned radio telescope at Arecibo. Foreign donations to keep it in order were a big source of income, too. Consequently the thought of anything going wrong with it was more than somewhat upsetting to a lot of people.
Dr. Juan Hencke was definitely one of those people. He was looking over last night’s first phase scan of the sky and quickly found what might most politely be called an aberration. “What’s this?”
Ted Mendez, his graduate assistant—legally, in a republic there is no such thing as a serf—said, “Oh, that’s a hot spot we first picked up after sunset.”
“I can see that. What is it? It looks like a goddamn supernova, except it’s elliptical.”
“Actually it’s a parabola at one end and tapered off at the other. It’s easier to see in the later images.”
Dr. Hencke immediately paged through the rest of the night’s scans. “It’s moving,” he whispered.
“Sure is. I figured it was one of those possible alien events you ordered me never to bother you with again,” Mendez said with no expression at all.
Barely controlling his temper, Hencke said, “This is clearly different.”
“They all were.”
“Have you given up plans of getting an advanced degree, Mendez?”
“As of last night, yes, sir. I made a phone call to someone who definitely was interested in the anomalies we’re supposed to be here to look for, and he’s made me a much better offer.”
“And what would that be?”
Ted smiled, backed his wheelchair out from under his desk, and said, “I’m not going to tell you. —And it’s not Mendez anymore, sir. It’s Skyhunter. And since I was still on payroll when I figured this out, I’ll tell you before I go: I’m almost certain that this is the asteroid the Watchstar people sent a nanomachine probe out to collect twenty-five years ago. And I am fully certain that it’s on an intercept course.” He rolled over to the elevator and punched the button, and the doors opened.
As he went in, Hencke obligingly gave him the setup for a dramatic last word: “Intercept with what?”
“Us,” he said as the doors closed.
Hencke spent the rest of the day on the phone, at least until the project director found out he was notifying people in the United States before his own boss.
I
You can’t go home again.
—THOMAS WOLFE
JUNE 2052 AD
“Dr. Glyer, they speak of you as if you might be a wizard,” Abdallah Chahine said.
Toby Glyer was running a looped view of Abdallah Chahine’s colonoscopy as performed at Memphis Central Hospital. Watching it felt like a Disney ride, up the intestine and back to start; early Disney, when they still had their sense of wonder. And humor. Walt would have loved this actual view for the ride—“Eaten by Monstro,” perhaps. That would be illegal today, of course. Whales were Soylent—politically green.
The surgeons had highlighted a constriction in Chahine’s bowel, and eleven tiny dark pores farther up.
The small, portly Egyptian had been careless with his diet for most of his fifty years of life. He was covering fear with belligerence. Toby was careful not to laugh. Not at the fear or the accent; the belligerence was courage, and the accent was … well, delicious. But— “Is this the same ‘they’ who say margarine is healthier than butter?”
Chahine’s eyes widened, and he actually smiled, a little, for a moment. “Not at all.”
“I’m not a wizard. I’m a very specialized doctor. These are diverticuli, blowouts on the colon. These dots are all that show. Underneath—”
Chahine said, “I know what diverticulosis is. How can you claim to cure it without surgery?”
Toby Glyer said distinctly, “You are going to need surgery.”
“Are you a surgeon?”
“No. The man who did these seems good at his job.” Toby froze the ride and pointed to the constriction. “You waited too long and this happened. Worse could follow. Diverticuli can do anything. This—” What word might serve? “—noose in your gut might close, and then you can’t eat, so you’ll die. You need a surgeon.”
Chahine waved it off. “They told me. I had hoped.”
“Hoped? You wanted to know if I would lie. Mr. Chahine, are you done testing me?”
“Give me the potion.”
Toby silently offered him a test tube with black oily stuff in the bottom, two centimeters deep. Chahine had already paid; the Swiss bank acknowledged receipt. Why was he arguing now?
“Nanotechnology,” Chahine said, careful with his pronunciation. He looked up into Toby’s eyes. The touch of relaxation was wearing off.
Toby said, “Call it wizardry. What I do isn’t legal anyway. I’m tired of repeating the lecture.”
Abdallah drank. Made a face. “It tastes like mineral oil. Not even that. There is no taste.”
“You still need the constriction removed,” Toby reminded him. “The rest of these little blowout patches won’t ever trouble you again. You’ve kept your appendix? That’ll never bother you either, and the, mmm, the spell lasts longer too.”
“Why, Doctor?”
“If I told you that I’d have to make you a partner. Good day, Abdallah Chahine.”
* * *
The file for the next patient indicated an American living in Switzerland, fifty-eight years old. Diverticulosis, of course. Toby could cure only one thing, but by using the Internet to search among ten billion people, he could find patients.
Interesting name, October Kroft. She was running partly on credit, but the first payment had come through.
He took her dose out of the safe, then showed her in.
She was six years younger than Toby, but she looked better than that: tall and still lean, wavy blond hair turning gray without hindrance. A gray business suit looked good on her. Hands off patients, he’d learned that early, but he did notice.
He turned to pick up the dose. “Some patients have questions,” he said.
“So do I,” she said.
With his back turned he knew her voice. He faced her again. “May! May Wyndham?”
“Hi, Toby.”
“You tracked me down? Is this some kind of joke?”
October Kroft didn’t hesitate. Her fists pulled her gray business suit apart, shirt up, waistband down. The scar ran vertically from her navel to … not far from her groin, at any rate. A pink worm, healing nicely, rows of dots still showing the marks of the staples.
Toby flinched. May grinned. “I don’t go to this much trouble for a joke.”
Not quite, anyway. “Okay. Sorry.” He handed her the vial.
She drank. Made a face and finished it. “You read my records. I wa
ited too long, obviously. What will this do for me? It’s nanotechnology, isn’t it?”
“May, that’s proprietary. Hey, how did you find me?”
“You popped up in my face! I’m in real estate now. My buyer saw my scar at a swimming party after he bought the house. He steered me to you. I couldn’t figure out how you became a doctor. But you’re specialized, aren’t you?”
“Very. You know what diverticuli are? It’s like having an appendix where nobody wants one. Little blowout pockets, scarred over. If you’re constipated, you pack more fecal matter in there every time and the diverticuli get bigger until something lethal happens. I knew a guy who— Sorry, May. Glass of water?”
“Thanks.”
He poured her a paper cupful. He said, “The nanos move along your gut until they find a pocket. They go into every pocket they find. They break up the fecal matter, which can be like cement after enough years, and carry it back out. It’s all strictly mechanical. If you still have your appendix, they stay in there for a while. Longer in Europeans.”
“What? Why?”
“Europeans think that the way to eat a cherry is to swallow the pit. Surgeons find cherry pits when they do an appendectomy. A few thousand nanos need months to break down a cherry pit.”
“Toby, I had a lot of reasons for not asking, but … what keeps your nanos from … well, eating the patient?”
“May, that’s proprietary.”
“But you’ve got something.”
Toby grinned like Punch and changed the subject. “You thought I’d be different? How?”
She said, “Pudgier, I think. Blond. You looked different on TV.”
“Well, the last time was twelve years ago.” His hair was mouse-brown and receding. “You are what I pictured,” Toby said. “You’ve still got a voice like fingers walking up a spinal cord. What have you been … after Wyndham Launch changed hands … May, I never hit on a patient, but Jesus! Have dinner with me. We have some serious catching up to do.”
“We had such ambitions.”
II
The conviction that something must be done is the parent of many bad measures.