“So I am finding. You…learned all this on Helicon.”

 “I learned to deal with essentials.”

 “Also to hate fluctuations. They can kill you.”

 He took a swig of the beer, still cold and biting. “I hadn’t thought of it that way.”

 “Why didn’t you say all this in the first place?”

 “I didn’t know it in the first place.”

 “A corollary, then: If you commit yourself to a woman you give away as much of yourself as you can, inside that enclosed space.”

 “The volume between the two of us.”

 “A geometric analogy is as good as any.” The tip of her tongue made her lower lip bulge out slightly, as it always did when she pondered a point. “And you commit yourself wholly to averting the price life exacts.”

 “The price of…fluctuations?”

 “If you can predict, you can avoid. Correct. Manage.”

 “This is awfully analytic.”

 “I’ve skipped over the hard parts, but they will be on the home­

 work assignment.”

 “Usually these kinds of talk use phrases like ‘optimally consolid­ ated self.’ I’ve been waiting for the jargon to come trotting out.” He had finished the bowl and felt much better.

 “Food is one of the life-affirming experiences.”

 “So that’s why I do it.”

 “Now you’re making fun of me.”

 “No, just working out the implications of the theory. I liked the

 part about hating unpredictability and fluctuations because they hurt people.”

 “So can Empires, if they fall.”

 “Right.” He finished the beer and thought about having another. Any more would dull him a little. He would prefer another way to take from him the edge he still felt.

 “Big appetite.” She smiled.

 “You have no idea. And the prospect of death can stimulate more than one kind of appetite. Let’s go back to that part about the homework assignment.”

 “You have something in mind.”

 He grinned. “You have no idea.”

 4.

 He savored his work all the more, since he had less time for it.

 Hari sat in his darkened office, absolutely still, watching the 3D numerics evolve like luminous fogs in the air before him.

 Empire scholars had known the root basics of psychohistory for millennia. In ancient times, pedants had charted the twenty-six stable and meta-stable social systems. There were plenty of devolved planets to study, fallen into barbarism—like the Porcos and their Raging Rituals, the Lizzies and their Gyno-Governs.

 He watched the familiar patterns form, as his simulation stepped through centuries of Galactic evolution. Some social systems proved stable only on small scales.

 In the air hung the ranks of whole worlds, caught in stable Zones: Primitive Socialism; Femo-Pastoralism; Macho Tribalism. These were the “strong attractors” of human sociology, islands in the chaos sea.

 Some societies labored through their meta-stability, then crashed: Theocracy, Transcendentalism, Macho Feudalism. This latter ap­ peared whenever people had metallurgy and agriculture. Planets which had slid a long way down the curve would manifest it.

 Imperial scholars had long justified the Empire, threaded by narrow wormholes and lumbering hyperships, as the best human social structure. It had indeed proved stable and benevolent.

 Their reigning model, Benign Imperial Feudalism, accepted that humans were hierarchical. As well, they were dynastically ambitious, liking the continuity of power and its pomp. They were quite de­ voted to symbols of unity, of Imperial grandeur. Gossip about the great was, for most people, the essence of history itself.

 Imperial power was moderated by traditions of noble leadership, the assumed superiority of those who rose to greatness. Beneath such impressive resplendence, as Cleon well knew, lay the bedrock of an extremely honest, meritocratic civil service. Without that, corruption would spread like a stain across the stars, corroding the splendor.

 He watched the diagram—a complex 3D web of surfaces, the landscape of social-space.

 Slow-stepped, he could see individual event-waves washing through the sim. Each cell in the grid got recomputed every clock cycle, readjusting every nearest-neighbor interaction in 3D.

 The working rules of thumb were not the true laws of physics, built up from fundamentals like maxion mechanics, or even from the simple NewTown Laws. Rather, they were rough algorithms that reduced intricate laws to trivial arithmetic. Society seen raw this way was crude, not mysterious at all.

 Then came chaos.

 He was viewing the “policy-space,” with its family of variables: degree of polarity, or power concentration; size of coalitions; con­ flict scale. In this simple model, learning loops emerged. Starting from a plateau period of seeming stability but not stasis, the system produced a Challenger Idea.

 This threatened stability, which forced formation of coalitions to oppose the challenge. Factions formed. Then they gelled. The coalitions could be primarily religious, political, economic, techno­ logical, even military—though this last was a particularly ineffective method, the data showed. The system then veered into a chaotic realm, sometimes emerging to new stability, sometimes decaying.

 In the dynamic system there was a pressure created by the con­ trast between people’s ideal picture of the world and the reality. Too big a difference drove fresh forces for change. Often the forces were apparently unconscious; people knew something was wrong, felt restive, but could not fix on a clear cause.

 So much for “rational actor” models, Hari thought. Yet some still clung to that obviously dumb approximation.

 Everyone thought the Empire was simple.

 Not the bulk of the population, of course, dazzled by the mix of cultures and exotica afforded by trade and communications from myriad worlds. They were perpetually distracted—an important damper on chaos.

 Even to social theorists, though, the basic structure and interrelations seemed to be predictable, with a moderate number of feedback loops, solid and traditional. Conventional wisdom held that these could be easily separated out and treated.

 Most important, there was central decision-making, or so most thought. The Emperor Knew Best, right?

 In reality, the Empire was a nested, ordered hierarchy: Imperial Feudalism. At the lower bound were the Zones of the galaxy, sometimes only a dozen light-years across, up to a few thousand light years diameter. Above that were Compacts of a few hundred nearby Zones. The Compacts interlocked into the Galactic cross­ linked system.

 But the whole thing was sliding downhill. In the complex dia­ gram, sparkling flickers came and went. What were those?

 Hari close-upped the flares. Zones of chaos, where predictability becomes impossible. These fiery eruptions might be the clue to why the Empire was failing.

 Hari felt in his soul that unpredictability was bad—for humanity, for his mathematics. But it was inescapable.

 This was the secret the Emperor and others must never know. That until he could rule chaos—or at least peer into it—psychohis-tory was a fraud.

 He decided to look at a single case. Maybe that would be cleaner.

 He selected Sark, the world which had found and developed the Voltaire and Joan sims. It billed itself as the Home of the New Renaissance—a common rhetorical posture, often adopted. They seemed bright and creative as he reviewed the status-grids.

 Hari yawned despite himself. Sure, Sark looked good for now. A booming economy. A leader in styles and fashion.

 But its profile classed it among the Chaos Worlds. They rose for a while, seeming to defy the damping mechanisms that held planets in the Imperial Equilibrium.

 Then their social fabric dissolved. They plummeted back into one of the Stasis States: Anarcho-Industrial for Sark, he would predict, from the data. No great fleets made this happen. The Em­ pire did not, despite impressions, rule by force. Social evolutions made the Chaos Worlds falter and die. Usually, the Galaxy as a whole suffered few repercussions.

 But lately, there had been more of them. And the Empire was visibly decaying. Productivity was down, incoherence in the social-spaces on the rise.

 Why?

 He got up and went for a workout at the gymnasium. Enough of the mind! Let his body sweat out the frustrations wrought by his intellect.

 5.

 He did not want to go to the Grand Imperial Universities Col­ loquy, but the Imperial Protocol Office leaned on him. “A First Ministerial candidate has obligations,” the officious woman had informed him.

 So he and Dors dutifully appeared at the enormous Imperial Festival Hall. His Specials wore discreet formal business suits, complete with the collar ruffles of mid-level meritocrats.

 “All the better to blend into the crowd,” Dors joked. Hari saw that everyone sized up the men in an instant and gingerly edged away. He would have been fooled.

 They entered a high, double-arched corridor, lined with ancient statuary which invited the passersby to lick them. Hari tried it, after carefully reading the glow-sign, which reassured him there was no biological risk. A long, succulent lick gave him a faint, odd flavor of oil and burnt apples, a hint of what the ancients found enticing.

 “What’s first on the agenda?” he asked his Protocol Officer.

 “An audience with the Academic Potentate,” she answered, adding pointedly, “Alone.”

 Dors disagreed and Hari negotiated a compromise. Dors got to stand at the doorway, no more. “I’ll have appetizers served to you there,” the Protocol Officer said testily.

 Dors gave her an icy smile. “Why is this, ah, ‘audience’ so im­ portant?”

 The Protocol Officer gave her a pitying look. “The Potentate carries much weight in the High Council.”

 Hari said soothingly, “And can throw a few votes my way.”

 “A bit of polite talk,” the Protocol Officer said.

 “I shall promise to—let me put this delicately—smooch his but­ tocks. Or hers, as the case may be.”

 Dors smiled. “Better not be hers.”

 “Intriguing, how the implications of the act switch with sex.”

 The Protocol Officer coughed and ushered him deftly through snapping screen curtains, his hair sizzling. Apparently even an Academic Potentate had need of personal security measures.

 Once within the formal staterooms, Hari found he was alone with a woman of considerable age and artificial beauties. So that was why the Protocol Officer had coughed.

 “How very nice of you to come.” She stood motionless, one hand extended, limp at the wrist. A waterfall effect spattered behind her, framing her body well.

 He felt as if he were walking into a still-life museum display. He didn’t know whether to shake her hand or kiss it. He shook it, and her look made him think he had chosen wrong.

 She wore a lot of embedded makeup, and from the way she leaned forward to make a point, he gathered that her pale eyes got her a lot of things other people did not receive.

 She had once been an original thinker, a nonlinear philosopher. Now meritocrats across the spiral arms owed her fealty.

 Before they had sat down, she gestured. “Oh, would you tune that wall haze?” The waterfall effect had turned into a roiling, thick fog. “Somehow it gets wrong all the time and the room doesn’t adjust it.”

 A way of establishing a hierarchy, Hari suspected. Get him used to doing little tasks at her bidding. Or maybe she was like some other women, who if they couldn’t get you to do minor services felt insecure. Or maybe she was just inept and wanted her waterfall back. Or maybe he just analyzed the hell out of everything, a mathist’s pattern.

 “I’ve heard remarkable things about your work,” she said, shifting from High Figure Used to Snappy Obedience to Gracious Lady Putting an Underling at Ease. He said something noncommittal. A tiktok brought a stim which was barely liquid, drifting down his throat and into his nostrils like a silken, sinister cloud.

 “You believe yourself practical enough for the ministership?”

 “Nothing is more practical, more useful, than a sound theory.”