Then he saw the rocks and knew he had chosen the right path. A wall of brown granite, dark and damp from the condensing fog, materialized before them. They heard it before they saw it; it made no sound, but its presence changed the acoustics of the forest. The fog was closing in, and they could barely see the silhouettes of scrubby, wind-gnarled mountain trees lined up uncomfortably along the top of the cliff.

Amid those trees was the silhouette of a human being.

"Quiet," Hackworth mouthed to his daughter, then reined Kidnapper to a stop.

The person had a short haircut and wore a bulky waist-length jacket with stretch pants; they could tell by the curve of the hips that it was a woman. Around those hips she had fastened an arrangement of neon green straps: a climbing harness. She wore no other outdoor paraphernalia, though, no knapsack or helmet, and behind her on the clifftop they could just make out the silhouette of a horse, prodding the ground with its nose. From time to time she checked her wristwatch.

A tenuous neon strand of rope hung down the bulging face of the cliff from where the woman stood. The last several meters dangled loosely in the mist in front of a small cozy pocket sheltered by the overhang.

Hackworth turned around to get Fiona's attention, then pointed something out: a second person, making his way along the base of the cliff, out of sight of the woman above. Moving carefully and quietly, he eventually reached the shelter of the overhang. He gingerly took the dangling end of the rope and tied it to something, apparently a piece of hardware fixed into the rock. Then he left the way he had come, moving silently and staying close to the cliff.

The woman remained still and silent for several minutes, checking her watch more and more frequently.

Finally she backed several paces away from the edge of the cliff, took her hands out of her jacket pockets, seemed to draw a few deep breaths, then ran forward and launched herself into space. She screamed as she did it, a scream to drive out her own fear. The rope ran through a pulley fixed near the top of the cliff.

She fell for a few meters, the rope tightened, the man's knot held, and the rope, which was somewhat elastic, brought her to a firm but not violent stop just above the wicked pile of rubble and snags at the base of the cliff. Swinging at the end of the rope, she grabbed it with one hand and leaned back, baring her throat to the mist, allowing herself to dangle listlessly for a few minutes, basking in relief.

A third person, previously unseen, emerged from the trees. This one was a middle-aged man, and he was wearing a jacket that had a few vaguely official touches such as an armband and an insignia on the breast pocket. He walked beneath the dangling woman and busied himself for a few moments beneath the overhang, eventually releasing the rope and letting her safely to the ground. The woman detached herself from the rope and then the harness and fell into a businesslike discussion with this man, who poured both of them hot drinks from a thermal flask.

"Have you heard of these people? The Reformed Distributed Republic," Hackworth said to Fiona, still keeping his voice low.

"I am only familiar with the First."

"The First Distributed Republic doesn't hang together very well– in a way, it was never designed to. It was started by a bunch of people who were very nearly anarchists. As you've probably learned in school, it's become awfully factionalized."

"I have some friends in the F.D.R.," Fiona said.

"Your neighbors?"

"Yes."

"Software khans," Hackworth said. "The F.D.R. works for them, because they have something in common-old software money. They're almost like Victorians– a lot of them cross over and take the Oath as they get older. But for the broad middle class, the F.D.R. offers no central religion or ethnic identity."

"So it becomes balkanized."

"Precisely. These people," Hackworth said, pointing to the man and the woman at the base of the cliff, "are R.D.R., Reformed Distributed Republic. Very similar to F.D.R., with one key difference."

"The ritual we just witnessed?"

"Ritual is a good description," Hackworth said. "Earlier today, that man and that woman were both visited by messengers who gave them a place and time-nothing else. In this case, the woman's job was to jump off that cliff at the given time. The man's job was to tie the end of the rope before she jumped. A very simple job-"

"But if he had failed to do it, she'd be dead," Fiona said.

"Precisely. The names are pulled out of a hat. The participants have only a few hours' warning. Here, the ritual is done with a cliff and a rope, because there happened to be a cliff in the vicinity. In other R.D.R. nodes, the mechanism might be different. For example, person A might go into a room, take a pistol out of a box, load it with live ammunition, put it back in the box, and then leave the room for ten minutes. During that time, person B is supposed to enter the room and replace the live ammunition with a dummy clip having the same weight. Then person A comes back into the room, puts the gun to his head, and pulls the trigger."

"But person A has no way of knowing whether person B has done his job?"

"Exactly."

"What is the role of the third person?"

"A proctor. An official of the R.D.R. who sees to it that the two participants don't try to communicate."

"How frequently must they undergo this ritual?"

"As frequently as their name comes up at random, perhaps once every couple of years," Hackworth said. "It's a way of creating mutual dependency. These people know they can trust each other. In a tribe such as the F.D.R., whose view of the universe contains no absolutes, this ritual creates an artificial absolute."

The woman finished her hot drink, shook hands with the proctor, then began to ascend a polymer ladder, fixed to the rock, that took her back toward her horse. Hackworth spurred Kidnapper into movement, following a path that ran parallel to the base of the cliff, and rode for half a kilometer or so until it was joined by another path angling down from above. A few minutes later, the woman approached, riding her horse, an old-fashioned biological model.

She was a healthy, open-faced, apple-cheeked woman, still invigorated by her leap into the unknown, and she greeted them from some distance away, without any of the reserve of neo-Victorians.

"How do you do," Hackworth said, removing his bowler.

The woman barely glanced at Fiona. She reined her horse to a gentle stop, eyes fixed on Hackworth's face. She was wearing a distracted look. "I know you," she said. "But I don't know your name."

"Hackworth, John Percival, at your service. This is my daughter Fiona."

"I'm sure I've never heard that name," the woman said.

"I'm sure I've never heard yours," Hackworth said cheerfully.

"Maggie," the woman said. "This is driving me crazy. Where have we met?"

"This may sound rather odd," Hackworth said gently, "but if you and I could both remember all of our dreams-which we can't, of course– and if we compared notes long enough, we would probably find that we had shared a few over the years."

"A lot of people have similar dreams," Maggie said.

"Excuse me, but that's not what I mean," Hackworth said. "I refer to a situation in which each of us would retain his or her own personal point of view. I would see you. You would see me. We might then share certain experiences together-each of us seeing it from our own perspective.

"Like a ractive?"

"Yes," Hackworth said, "but you don't have to pay for it. Not with money, anyway."

The local climate lent itself to hot drinks. Maggie did not even take off her jacket before going into her kitchen and putting a kettle on to boil. The place was a log cabin, airier than it looked from the outside, and Maggie apparently shared it with several other people who were not there at the moment. Fiona, walking to and from the bathroom, was fascinated to see evidence of men and women living and sleeping and bathing together.