by Larry Niven
The Hindmost chirped. The racing rim wall opened behind him -- "Stet?"
"Yes, stet, if it doesn't hide you from me."
-- rim wall moving at a blur, its edge far above, the tops of the spill mountains far below. The probe must be about three hundred miles up, Louis thought.
The Hindmost chirped. Louis looked for results, but he couldn't see -- wait, now. Night-shadowed, the passing rim wall had picked up a blue highlight: the reflection of a small fusion drive. Floating equations told it better: some of the numbers were reeling down.
Three ghosts still danced with the Hindmost, and Louis knew them. Their hairstyles differed, but they were all Nessus.
Acolyte was gnawing on something that dripped red. It was not an appetizing sight, but Louis was suddenly starved. He tapped at the kitchen wall with one eye for the holograms.
Bram asked, "Hindmost, what do you know of Teela Brown?"
The Hindmost sang like a bronze bell. A third hologram opened behind the Hindmost: a table of contents, as best Louis could tell. The cabin was crowded with images.
Bram flared in anger. "Come here. Come here now!"
The Hindmost didn't hesitate. He stepped and was beside them. "I intended no harm."
"I prefer you here. Louis, Hindmost, Acolyte, I'm trying to paint a picture of a protector in my mind. I have my murky view of Cronus and I knew Anne intimately, but Teela Brown is an alien protector. Soon we must face alien protectors. Hindmost, what have you shown me?"
"These are records on the Lucky Human Project. My administration felt that human allies could do us good. Humans are lucky. We would make them effective by making them luckier. The experiment was local to one planet, Earth. We added a lottery to the formal qualifications that earn a birthright. We kept track of babies born through luck. We financed a social network so that the children might meet and breed."
"Was she lucky?"
Louis wasn't listening, definitely wasn't listening. When he'd fought free of the Ringworld, Teela had stayed behind by her own choice. Louis had had forty years to avoid thinking about Teela Brown.
"She was a sixth-generation lottery winner, but Teela was not lucky for puppeteers, nor for her associates. I cannot think she was lucky for herself. Any creature seeks homeostasis. Teela lost her mate, then her gender identity and shape, then her life. But luck is a thing of dubious interpretation."
Acolyte spoke. "What if she sought a cause worth dying for?"
Louis gaped. Acolyte added, "Or what if she only wanted to be more intelligent? Like my father. Like me. Luck gave her those things."
Bram said, "Louis?"
"Maybe. Interesting interpretation." Forty years, and he'd never seen what was obvious to this eleven-year-old cat!
"Anything further?"
Louis closed his eyes. He could see her, touch her. "A freak accident took her away from us. Luck. When we found her, she'd found Seeker. Big, brawny explorer type, a wonderful guide, and I guess she was in love with him, too --"
"Was she your mate or his?"
"Serial polygamy. Skip it --"
"She left you for him?"
"Not *just* for Seeker. Bram, she'd found this -- this *huge* toy. It never would have occurred to Teela that it was beyond her, too big to play with. That *anything* was beyond her."
"She wanted to play with the Arch? Without destroying it, of course. And only a protector can do that?"
Louis rubbed his eyes.
"So you left her on the Ringworld. And then?"
"Seeker must have led her to the Map of Mars, or told her enough that she could guess the rest. She knew going in that she was entering a strange place, a place of secrets.
"She ... let's see ... she wakes as a protector. Seeker's dead. Teela's a protector in the Repair Center. She plays around. She finds out how to turn the sun into a superthermal laser. Blasts a few comets?"
"She did that."
"She learns how to display telescope views with the Meteor Defense setup. She notices that the Ringworld has a wobble to it. She finds attitude jets on the rim wall, but most of them are gone. Any protector could predict the results of that.
"She goes to the rim wall. Bram, did she take roots with her?"
"Roots and a flowering plant and thallium oxide."
"She finds City Builder ships built around the rim attitude jets. Anne may have replaced some of those ... yeah. That's what your Anne was doing: intercept every City Builder ship as it comes back from the stars, tear out the Bussard ramjets and mount them on the rim. It's just another thing Halrloprillalar never told me. She and her crew must have been evicted from their ship, sent back through the rim wall by an angry protector."
Bram waited.
"Poor tanj Prill. That could twist a person's mind."
Waited.
"So there's already a few attitude jets back in place, but all Teela sees is that the ship builders haven't stolen them all yet. She takes over Anne's job. It's urgent. She turns some breeders into protectors. She told me about those: a Spill Mountain People, a vampire, a Ghoul. They all start pulling motors out of returning ships and remounting them.
"They had twenty in place and no more ships in view, and the motors didn't have enough power by themselves. Teela left the other protectors tending the motors. She came back to the Repair Center. She must have known what she was going to do next. She didn't see Hot Needle of Inquiry coming at her until she was using the Repair Center telescope again."
Acolyte said, "She must have had a telescope on the rim, Louis."
"Sure, and it must have been good enough to see the big City Builder ships coming in. Needle's much smaller."
"Would she recognize Needle?"
"A General Products number-three hull? Sure."
Bram asked, "How could Needle affect her plans?"
"What did I tell you about reading a protector's mind, Bram?"
"But you must try."
Louis didn't *want* to try. "Here's what Teela told me. She just couldn't make herself kill a trillion people even to save thirty trillion. Protector intelligence and Teela Brown empathy: she could feel their deaths. She knew it had to be done, and she knew we'd figure out how, me and Chmeee and the Hindmost, and she couldn't let us do it, either. She was inviting us to kill her, Bram."
"I watched her fight. I could have fought better while dead."
"Yeah. It was the fight of my life, but nobody outfights a protector."
"If she knew she couldn't play a plasma jet along the rim wall, why did she return to the Repair Center?" Silly question. Bram didn't wait for an answer. "What did she really want?"
Louis shook his head. "What do protectors want? That's one thing we learned about you. Your motives are hard-wired. You protect your genetic line. When the line dies out, you stop eating and die. Teela didn't have children on the Ringworld, but there were hominids. Relatives, if you close one eye and squint a little. She *had* to save them. Why wait? With the Ringworld sliding off balance --"
Bram brushed it away. "She waited for Hot Needle of Inquiry, for puppeteer-derived computer programs. I watched you use them and was glad I had not interfered."
Oh. "But why not just say so? Tanj dammit, why the fight?" Wait, now -- "Bram, did Anne leave just after you killed Cronus?"
"She took several days to prepare."
"And that was just under seven thousand falans ago?"
"Yes."
"Around twelve hundred A.D., my calendar. Did she take roots? And does she have to come back for more?"
"Anne took roots and a blooming plant and some thalium [sic -- should be "thallium"] oxide. She planted tree-of-life but the crop failed after a time, so she came back near fi
ve thousand falans ago. She stayed with me for not long. I haven't seen her since. Either she grew a better garden or she's dead."
"Yeah. Teela had the same idea? Roots, plants, thallium oxide. If there's a good place to plant all that, then Anne's garden was in it. Teela would know what it was."
"Anne would hide it well."
"You can't hide plants from sunlight. She couldn't put it where any passing hominid would sniff it. She'd want it within her reach, on a spill mountain, in a place even hot-air balloons couldn't invade. A fissure, a steep valley, maybe. And now we have to guess whether Teela saw it."
"And if she did?"
Louis sighed. "Bram, what have you got on *living* protectors?"
"Hindmost, show him. I propose to bathe."
Chapter 25 -
Default Option
A hundred miles above the spill mountain tops, the probe accelerated. The Ringworld raced toward and past it like a frozen river bigger than worlds, but no longer at 770 miles per second. The probe was catching up.
Louis asked the puppeteer, "Are we in view of that comet installation you didn't blast?"
"Yes, it's far enough above the Ringworld plane, but we will have landed before the light reaches the comet."
Acolyte reclined, huge and silent. Chmeee had sent him to learn, and he had been learning from Bram for these past 2.2 falans. Teaching him *wisdom* would be a neat trick, Louis thought. Protectors had intelligence coming out of their ears, but *wisdom*? Could a Kzin see the difference?
"And you've blasted everything else that can see us."
"Yes."
"Stet. Show us the rim."
"I can't really show you protectors, Louis. It's what Bram asked, but I cannot magnify so greatly."
"What have you got?"
The Hindmost had months, falans, of observing the rim wall and the spill mountains. Winking heliographs were everywhere, not just on the rim wall. Several times the probe had caught daylit flashes from -- one presumed -- client species on the flatlands.
A village flashed past, and the Hindmost froze it for their eyes: a thousand houses spreading out from one side of a magnificent waterfall, eight to ten thousand feet high. On the other side of the falls, a dockyard for hot air balloons, marked by a cliff splashed with bright orange paint. Below the dockyard, clustered factories and warehouses ran down the ice and rocks to another orange boulder and a lower landing pad. Come in high or come in low, travelers would find refuge.
The Hindmost jumped the view to another village fifty million miles away. A spread across a shallow green hillside: houses with sloped sod roofs, and a vertical row of industrial works with orange-marked landing pads above and below.
Louis said, "Acolyte, you've seen a lot more of this than I have. What am I likely to miss?"
"I can't guess what you might miss, Louis. They have no more problem with garbage disposal than a school of fish. They --"
Louis laughed widely, white teeth showing. Acolyte waited it out. "Their houses differ but their placement follows a pattern. Balloons and factories are alike everywhere. Bram and I surmise that the Night People mirrors can relay designs, maps, weather alerts, perhaps written music: a trade in ideas."
"Trade between stars is like that."
The rim wall was a continuous sheet of scrith, of Ringworld floor material as strong as the force that held an atomic nucleus together. Even that force wasn't as strong as a meteoroid moving at Ringworld speed, and Louis noted a punch hole high up on the rim wall, a few million miles antispin from the *other* Great Ocean. Otherwise the great empty mountings stood three million miles apart along a featureless rim, and a slender thread ran along the top for a third of its length. They'd seen that eleven years ago: a maglev track, never finished.
Twenty-three of the mounts now held motors. At highest magnification, the tiny pairs of toroids were just visible.
"Here is what they look like firing." The puppeteer jumped the view, fast-forward.
The change was not great. Hydrogen fusion radiates mostly X rays. A fusion motor radiates visible light because it is hot, or because working mass has been added to increase thrust. When a rim wall motor was firing, the wire outline glowed white-hot, and flexed against the plasma's magnetic fields. The toroids were the wasp-waist constriction in an hourglass of white-hot wire, and an indigo ghost flame ran down the axis. Twenty-two of those in a row.
The Hindmost displayed successive views of work around the twenty-third motor. There were cranes and cables big enough to see, and flatbed things that might be used for magnetic levitation, but not a hope of seeing anything man-sized.
And all Louis could think of was his need to talk where Bram couldn't hear.
The protector was using the bath setup in the crew cabin. No doubt that equipment had kept Chmeee and Louis sane, and Harkabeeparolyn and Kawaresksenjajok, too. Still, it was cramped and complicated and primitive. They could hear the whisper of spray through the wall.
Louis said, testing, "Given he bathes at all, I'm surprised he didn't use your cabin."
"Louis, I wish now that I *could* show you my cabin. The dedicated stepping disk is hardwired. It *cannot* move an alien."
The Kzin rumbled, "You value your privacy greatly."
"You know better. I want company," the Hindmost said. "Louis or even you, if I cannot surround myself with my kind. We follow our fears. I followed my fear when I shaped this ship."
"You persuaded Bram of that?"
"I hope so. It's true."
The probe was an hour short of matching the Ringworld's spin. Louis said, "We're going to have to use pressure suits. Let's do something about them."
"I keep my own well-maintained," the puppeteer said.
"Stet. Send me and Acolyte to the lander bay."
"I should come," the Hindmost said. "There's other equipment I should see to."
They flicked out.
***
"We cannot be heard here," the Hindmost assured them.
Acolyte snorted. Louis said, "Suppose a protector-level intelligence really wanted to hear us?"
"No, Louis. I intended to spy on you and Chmeee and --" Harkabeeparolyn hadn't made the cut. "I made this my listening post. No entity could add a spy device in the lander bay without signaling me."
Maybe. "Hindmost, aren't you safe when you're in your own cabin?"
"Bram has a way to attack me there."
"Can you block it?"
"I haven't worked out what he has."
"A good bluff? Bram's had a long time to work on you. He has you terrified."
The Hindmost's gaze converged on Louis: binocular vision with a baseline of three feet. "You have never understood us. The hidden protector frightened me from the first. I remain frightened. However you plan to circumvent Bram, I may accept the risk or reject it, but only on the odds. I do not turn my mind from danger."
"I don't expect to break my contract."
"Excellent."
There were pressure suits and air racks designed for humans. He and Bram would need two of everything. Louis checked pressure zips on the suits and the racks. He emptied waste recycler reservoirs and filled nutrient reservoirs, flushed the interiors of the suits and the air and water tanks, topped off the air, charged the batteries.
Acolyte was tending his own suit. The Hindmost was inspecting a stack of stepping disks.
Louis said, "I know why Teela Brown died."
The Hindmost said, "Protectors die fairly easily, when they no longer feel needed --"
Louis shook his head. "She found something. Maybe it was Anne's garden, maybe just fingerprints on the rim wall motors. Whatever, she knew there was a protector in the Repair Center. She had
to get Needle into the Map of Mars, but when she did that, she made us hostages. The only way to make us safe was to die. But --"
"Louis, we don't have time. What do you want of us?"
"I want to change the stepping disk pattern without Bram knowing. Then I may want to change it back. I'm not sure I'm right yet. I need a default option."
The Kzin asked, "Default option?"
The Hindmost answered, "Decide in advance what you will do if you don't have time to decide."
"Like the first move you learn in fighting with a Kzin dagger, a wtsai," Louis said. "If you're attacked too fast to think, there's your training."
"The disembowel."
"Whatever. I just knew there must be one. Epees and handguns and hand-to-hand and yogatsu, it doesn't matter: you train the moves into your reflex arcs so you don't have to make up something while you're being attacked. Likewise, you instruct a computer on what to do if you don't tell it what to do."
"Clever notion, said the Kzin.
"Hindmost, I don't quite understand your stepping disk network ..."
They discussed it. The system wanted to know that you really meant the change you'd whistled or typed in. *Push the edge of the disk down.*
"Stet. Now I can do this and you cannot notice. We have deniability. Acolyte, I'll need a distraction."
"See if you can describe it," Acolyte said.
"I haven't the faintest bloody idea. I only need it for about two breaths."
***
As they flicked through to the cabin, the Hindmost was saying, "Louis, are you aware that you were dying?"
Louis smiled faintly. "Tradition says that everyone is dying. Exceptions may be made for puppeteers and protectors. Hello, Bram. Any change?"
Bram was in a rage. "Hindmost, amplify the light and zoom. The village!"
The probe was moving through shadow; but much closer than the distant oncoming band of daylight was a glimpse of pattern crusting the dim snow-colors of a passing spill mountain.
The Hindmost sang flute and strings. The pattern brightened and began to expand.
