On her way back down to the tube, she happened to pass by a bookstall, where she picked up a paper copy of one of her favorite history books and downloaded a whole series of novels set on Old Earth. The paper copy was an extravagance, something she would add to her little library the next time she made it to one of her caches. For like a lot of young Moirans, Kath Two didn’t even try to establish a fixed home. With a home came a social circle, and perhaps a family. All of which was fine for the people of the other races. But until a Moiran “took a set,” such permanent arrangements were unwise, placing husband, children, coworkers, and friends at risk of waking up one day to find that their wife, mother, colleague, or pal had effectively died and been replaced by someone else. So rather than renting apartments, young Moirans opted for storage caches in places they were wont to visit. Sometimes it was a shelf in a friend’s closet, sometimes a locker in a Survey or military base, sometimes a commercial niche in a big city with a robot doorkeeper that would ID you. Abandoned caches were legion, their contents forever being sold at auction.

Kath Two was the sort of person whose caches were apt to be crammed with paper books. For her, the electronic books were an insurance policy of sorts. The four-day elevator ride might be nothing more than a prelude to further journeys, some of which might take her to places with little to no bandwidth, and nothing was worse than getting stuck in a situation like that with nothing to read.

Elsewhere on the Great Chain was a block-long historical museum, stacked by era, with one floor for each millennium, beginning with the pre-Zero world on the ground floor and proceeding upward. Of course, very few physical artifacts remained from pre-Zero, so that floor consisted mostly of pictures and reconstructed environments. But the Arkies had been allowed to bring a few possessions into space with them, and some of those had survived the Epic and the ensuing five thousand years. So it was possible to look at actual smartphones and tablets and laptops that had been manufactured on Old Earth. They did not work anymore, but their technical capabilities were described on little placards. And they were impressive compared to what Kath Two and other modern people carried around in their pockets. This ran contrary to most people’s intuition, since in other areas the achievements of the modern world—the habitat ring, the Eye, and all the rest—were so vastly greater than what the people of Old Earth had ever accomplished.

It boiled down to Amistics. In the decades before Zero, the Old Earthers had focused their intelligence on the small and the soft, not the big and the hard, and built a civilization that was puny and crumbling where physical infrastructure was concerned, but astonishingly sophisticated when it came to networked communications and software. The density with which they’d been able to pack transistors onto chips still had not been matched by any fabrication plant now in existence. Their devices could hold more data than anything you could buy today. Their ability to communicate through all sorts of wireless schemes was only now being matched—and that only in densely populated, affluent places like the Great Chain.

There was no telling, of course, what was going on in the Red zone between the turnpikes. Signals intelligence shining out into space from their part of the habitat ring suggested that the Aïdans were at least as advanced, in their use of mobile communications, as people here. Because they were also quite good at encryption, there was no way of telling what they were saying to one another. But Blue, for its part, had made a conscious decision not to repeat what was known as Tav’s Mistake.

It was unfair, of course, for billions of people to focus blame on one representative of his culture who had died in a bad way five thousand years ago. The Epic, however, tended to have this effect on people’s thinking. In the same way that certain people of Old Earth, raised on the Bible, would have referred to masturbation as the Sin of Onan, those of the modern world tended to classify personal virtues and failings in terms of well-known historical figures from the era of the Cloud Ark, the Big Ride, and the first generations on Cleft. Fair or not, Tavistock Prowse would forever be saddled with blame for having allowed his use of high-frequency social media tools to get the better of his higher faculties. The actions that he had taken at the beginning of the White Sky, when he had fired off a scathing blog post about the loss of the Human Genetic Archive, and his highly critical and alarmist coverage of the Ymir expedition, had been analyzed to death by subsequent historians. Tav had not realized, or perhaps hadn’t considered the implications of the fact, that while writing those blog posts he was being watched and recorded from three different camera angles. This had later made it possible for historians to graph his blink rate, track the wanderings of his eyes around the screen of his laptop, look over his shoulder at the windows that had been open on his screen while he was blogging, and draw up pie charts showing how he had divided his time between playing games, texting friends, browsing Spacebook, watching pornography, eating, drinking, and actually writing his blog. The statistics tended not to paint a very flattering picture. The fact that the blog posts in question had (according to further such analyses) played a seminal role in the Break, and the departure of the Swarm, only focused more obloquy upon the poor man.

Anyone who bothered to learn the history of the developed world in the years just before Zero understood perfectly well that Tavistock Prowse had been squarely in the middle of the normal range, as far as his social media habits and attention span had been concerned. But nevertheless, Blues called it Tav’s Mistake. They didn’t want to make it again. Any efforts made by modern consumer-goods manufacturers to produce the kinds of devices and apps that had disordered the brain of Tav were met with the same instinctive pushback as Victorian clergy might have directed against the inventor of a masturbation machine. To the extent that Blue’s engineers could build electronics of comparable sophistication to those that Tav had used, they tended to put them into devices such as robots. Cleft’s initial population had been eight humans and hundreds of robots (thousands, if nats were counted as individuals). Both numbers had expanded since then. Only in the last century had the human population pulled even with that of non-nat robots.

The end result, for a young woman in a bookstall above a tube station on the Great Chain, was that she was dwelling in habitats, and being moved around by machines, far beyond the capabilities of Old Earth. She was being served and looked after by robots that were smarter and more robust than their ancestors—the Grabbs and so on that Eve Dinah had programmed on Izzy. And yet the information storage capacity of her tablet, and its ability to connect, were still limited enough that it made sense for her to download books over a cable while that was easy, and to make room for them in the tablet’s storage chips by deleting things she had already read.

That sorted, she rode transit to the Off Ramp, where she climbed into a capsule, facing backward, and felt deceleration push her back into her couch as it was flung off the Great Chain into a tube lined with electromagnetic decelerators.

Back now in the zero gee environment of the Eye’s nonrotating frame, she began to navigate its internal companionways, pushing herself along lighted tubes marked with the icon of Cradle: a pair of mountains enclosed within a semicircular dome. This led her, within a few minutes, to a transit station where she and two random strangers climbed into a four-person bubble that presently went into motion and began to whoosh at greater and greater speed down a long and perfectly straight tube. They were traveling from the rim of the great Eye’s iris out to its inner vertex, the one closest to Earth, a distance of some eighty kilometers, and so hand-over-handing their way down a shaft wasn’t an option. Kath Two, who had been awake now for something like sixteen hours, felt herself dozing off.