“The males need it, the females use it.”

 “Ummm, you’ve been taking notes.”

 “If I’m going to model pans as a sort of simplified people, then I must.”

 “Model pans?” came the assured tones of ExSpec Vaddo. “They’re not model citizens, if that’s what you mean.” He gave them a sunny smile and Hari guessed this was more of the obligatory friendliness of this place.

 Hari smiled mechanically. “I’m trying to find the variables that could describe pan behavior.”

 “You should spend a lot of time with them,” Vaddo said, sitting at the table and holding up a finger to a waiter for a drink. “They’re subtle creatures.”

 “I agree,” said Dors. “Do you ride them very much?”

 “Some, but most of our research is done differently now.” Vaddo’s mouth twisted ruefully. “Statistical models, that sort of thing. I got this touring idea started, using the immersion tech we had de­ veloped earlier, to make money for the project. Otherwise, we’d have had to close.”

 “I’m happy to contribute,” Hari said.

 “Admit it—you like it,” Dors said, amused.

 “Well, yes. It’s…different.”

 “And good for the staid Professor Seldon to get out of his shell,”

 she said.

 Vaddo beamed. “Be sure you don’t take chances out there. Some of our customers think they’re superpans or something.”

 Dors’ eyes flickered. “What danger is there? Our bodies are in slowtime, back here.”

 Vaddo said, “You’re strongly linked. A big shock to a pan can drive a back-shock in your own neurological systems.”

 “What sort of shock?” Hari asked.

 “Death, major injury.”

 “In that case,” Dors said to Hari, “I really do not think you should immerse.”

 Hari felt irked. “Come on! I’m on vacation, not in prison.”

 “Any threat to you—”

 “Just a minute ago you were rhapsodizing about how good for me it was.”

 “You’re too important to—”

 “There’s really very little danger,” Vaddo came in smoothly. “Pans don’t die suddenly, usually.”

 “And I can bail out when I see danger coming,” Hari added.

 “But will you? I think you’re getting a taste for adventure.”

 She was right, but he wasn’t going to concede the point. If he wanted a little escape from his humdrum mathematician’s routine, so much the better. “I like being out of Trantor’s endless corridors.”

 Vaddo gave Dors a confident smile. “And we haven’t lost a tourist yet.”

 “How about research staff?” she shot back.

 “Well, that was a most unusual—”

 “What happened?”

 “A pan fell off a ledge. The human operator couldn’t bail out in time and she came out of it paralyzed. The shock of experiencing death through immersion is known from other incidents to prove fatal. But we have systems in place now to short circuit—”

 “What else?” she persisted.

 “Well, there was one difficult episode. In the early days, when we had simple wire fences.” The ExSpec shifted uneasily. “Some predators got in.”

 “What sort of predators?”

 “A primate pack hunter, Carnopapio grandis. We call them ra-boons, because they’re genetically related to a small primate on another continent. Their DNA—”

 “How did they get in?” Dors insisted.

 “They’re somewhat like a wild hog, with hooves that double as diggers. They smelled game—our corralled animals. Dug under the fences.”

 Dors eyed the high, solid walls. “These are adequate?”

 “Certainly. Raboons share DNA with the pans and we believe they’re from an ancient genetic experiment. Someone tried to make a predator by raising the earlier stock up onto two legs. Like most bipedal predators, the forelimbs are shortened and the head carried forward, balanced by a thick tail they use for signaling to each other. They prey on the biggest herd animals, the gigantelope, eating only the richest meat.”

 “Why attack humans?”

 “They take targets of opportunity, too. Pans, even. When they got into the compound, they went for adult humans, not children—a very selective strategy.”

 Dors shivered. “You look at all this very…objectively.”

 “I’m a biologist.”

 “I never knew it could be so interesting,” Hari said to defuse her apprehension.

 Vaddo beamed. “Not as involving as higher mathematics, I’m sure.”

 Dors’ mouth twisted with wry skepticism. “Do you mind if guests carry weapons inside the compound?”

 9.

 He had a glimmering of an idea about the pans, a way to use their behaviors in building a simple toy model of psychohistory. He might be able to use the statistics of pan troop movements, the ups and downs of their shifting fortunes.

 Pictured in system-space, living structures worked at the edge of a chaotic terrain. Life as a whole harvested the fruits of a large menu of possible path-choices. Natural selection first achieved, then sus­ tained this edgy state.

 Whole biospheres shifted their equilibrium points amid energetic flowthrough—like birds banking on winds, he thought, watching some big yellow ones glide over the station, taking advantage of the updrafts.

 Like them, whole biological systems sometimes hovered at stag­ nation points. Systems were able to choose several paths of descent. Sometimes—to stretch the analogy—they could eat the tasty insects which came up to them on those same tricky breezes.

 Failure to negotiate such winds of change meant the pattern for­ feited its systemic integrity. Energies dissipated. Crucial was the fact that any seemingly stable state was actually a trick of dynamic feedback.

 No static state existed—except one. A biological system at perfect equilibrium was simply dead.

 So, too, psychohistory?

 He talked it over with Dors and she nodded. Beneath her appar­ ent calm she was worried. Since Vaddo’s remark she was always tut-tutting about safety. He reminded her that she had earlier urged him to do more immersions. “This is a vacation, remember?” he said more than once.

 Her amused sidewise glances told him that she also didn’t buy his talk about the toy modeling. She thought he just liked romping in the woods. “A country boy at heart,” she chuckled.

 So the next morning he skipped a planned trek to view the gi­ gantelope herds. Immediately he and Dors went to the immersion chambers and slipped under. To get some solid work done, he told himself.

 “What’s this?” He gestured to a small tiktok stationed between their immersion pods.

 “Precaution,” Dors said. “I don’t want anyone tampering with our chambers while we’re under.”

 “Tiktoks cost plenty out here.”

 “This one guards the coded locks, see?” She crouched beside the tiktok and reached for the control panel. It blocked her.

 “I thought the locks were enough.”

 “The security chief has access to those.”

 “And you suspect her?”

 “I suspect everyone. But especially her.”

 The pans slept in trees and spent plenty of time grooming each other. For the lucky groomer a tick or louse was a treat. With enough, they could get high on some peppery-tasting alkaloid. He suspected the careful stroking and combing of his hair by Dors was a behavior selected because it improved pan hygiene. It certainly calmed Ipan, also.

 Then it struck him: pans groomed rather than vocalizing. Only in crises and when agitated did they call and cry, mostly about breeding, feeding, or self-defense. They were like people who could not release themselves through the comfort of talk.

 And they needed comfort. The core of their social life resembled human societies under stress—in tyrannies, in prisons, in city gangs. Nature red in tooth and claw, yet strikingly like troubled people.

 But there were “civilized” behaviors here, too. Friendships, grief, sharing, buddies-in-arms who hunted and guarded turf together. Their old got wrinkled, bald, and toothless, yet were still cared for.

 Their instinctive knowledge was prodigious. They knew how to make a bed of leaves as dusk fell, high up in trees. They could climb with grasping feet. They felt, cried, mourned—without being able to parse these into neat grammatical packages, so the emotions could be managed, subdued. Instead, emotions drove them.

 Hunger was the strongest. They found and ate leaves, fruit, in­ sects, even fair-sized animals. They loved caterpillars.

 Each moment, each small enlightenment, sank him deeper into Ipan. He began to sense the subtle nooks and crannies of the pan mind. Slowly, he gained more cooperative control.

 That morning a female found a big fallen tree and began banging on it. The hollow trunk boomed like a drum and all the foraging party rushed forward to beat it, too, grinning wildly at the noise.

 Ipan joined in. Hari felt the burst of joy, seethed in it.

 Later, coming upon a waterfall after a heavy rain, they seized vines and swung among trees, out over the foaming water, screeching with delight as they performed twists and leaps from vine to vine.

 They were like children in a new playground. Hari got Ipan to make impossible moves, wild tumbles and dives, propelling him forward with abandon—to the astonishment of the other pans.

 They were violent in their sudden, peevish moments—in hustling females, in working out their perpetual dominance hierarchy, and especially in hunting. A successful hunt brought enormous excite­ ment: hugging, kissing, pats. As the troop descended to feed, the forest rang with barks, screeches, hoots, and pants. Hari joined the tumult, danced with Sheelah/Dors.

 He had expected to have to repress his prim meritocrat dislike of mess. Many meritocrats even disliked soil itself. Not Hari, who had been reared among farmers and laborers. Still, he had thought that long exposure to Trantor’s prissy aesthetics would hamper him here. Instead, the pans’ filth seemed natural.

 In some matters he did have to restrain his feelings. Rats the pans ate headfirst. Larger game they smashed against rocks. They devoured the brains first, a steaming delicacy.

 Hari gulped—metaphorically, but with Ipan echoing the im-pulse—and watched, screening his reluctance. Ipan had to eat, after all.

 At the scent of predators, he felt Ipan’s hair stand on end. Anoth­ er tangy bouquet made Ipan’s mouth water. He gave no mercy to food, even if it was still walking. Evolution in action; those pans who had showed mercy in the past ate less and left fewer descend­ ants. Those weren’t represented here anymore.

 For all its excesses, he found the pans’ behavior hauntingly famil­ iar. Males gathered often for combat, for pitching rocks, for blood sports, to work out their hierarchy. Females networked and formed alliances. There were trades of fa­ vors for loyalty, kinship bonds, turf wars, threats and displays, protection rackets, a hunger for “respect,” scheming subordinates, revenge—a social world enjoyed by many people that history had judged “great.”

 Much like the Emperor’s court, in fact.

 Did people long to strip away their clothing and conventions, bursting forth as pans? A brainy pan would be quite at home in the Imperial gentry…

 Hari felt a flush of revulsion so strong Ipan shook and fidgeted. Humanity’s lot had to be different, not this primitive horror.

 He could use this, certainly, as a test bed for a full theory. Then humankind would be self-knowing, captains of themselves. He would build in the imperatives of the pans, but go far beyond—to true, deep psychohistory.

 10.

 “I don’t see it,” Dors said at dinner.

 “But they’re so much like us! We must have shared some connec­ tions.” He put down his spoon. “I wonder if they were house pets of ours, long before star travel?”

 “I wouldn’t have them messing up my house.”

 Adult humans weighed little more than pans, but were far weaker. A pan could lift five times more than a well-conditioned man. Human brains were three or four times more massive than a pan’s. A human baby a few months old already had a brain larger than a grown pan. People had different brain architecture, as well.

 But was that the whole story? Hari wondered.
 Give pans bigger brains and speech, ease off on the testosterone, saddle them with more inhibitions, spruce them up with a shave and a haircut, teach them to stand securely on hind legs—and you had deluxe model pans that would look and act rather human.