Green Mars. Kim Stanley Robinson

subsistence diets. Their lecterns set the initial conditions and then they tapped away, looking bored or nervous or impatient or absorbed, using formulas provided by the table, or else supplying some of their own.

      It occupied them until lunch, and then all afternoon. Art had always enjoyed games, and he and Amy always finished well ahead of the others. Their results for a maximum sustainable population ranged from one hundred million (the “immortal tiger” model, as Fort called it) to thirty billion (the “ant farm” model).

      “That’s a big range,” Sam noted.

      Fort nodded, and eyed them patiently.

      “But if you look only at models with the most realistic conditions,” Art said, “you usually get between three and eight billion.”

      “And the current population is about twelve billion,” Fort said. “So, say we’re overshot. Now what do we do about that? We’ve got companies to run, after all. Business isn’t going to stop because there’s too many people. Full world economics isn’t the end of economics, it’s just the end of business as usual. I want Praxis to be ahead of the curve on this. So. It’s low tide, and I’m going back out. You’re welcome to join me. Tomorrow we’ll play a game called Overfull.”

      With that he left the room, and they were on their own. They went back to their rooms, and then, as it was close to dinner time, to the dining hall. Fort was not there, but several of his elderly associates from the night before were; and joining them tonight was a crowd of young men and women, all of them lean, bright-faced, healthy-looking. They looked like a track club or a swim team, and more than half were women. Sam and Max’s eyebrows shot up and down in a simple Morse code, spelling “Ah ha! Ah ha!” The young men and women ignored that and served them dinner, then returned to the kitchen. Art ate quickly, wondering if Sam and Max were correct in their suppositions. Then he took his plate into the kitchen and started to help at the dishwasher, and said to one of the young women, “What brings you here?”

      “It’s a kind of scholarship programme,” she said. Her name was Joyce. “We’re all apprentices who joined Praxis last year, and we were selected to come here for classes.”

      “Were you by chance working on full world economics today?”

      “No, volleyball.”

      Art went back outside, wishing he had got selected to their programme rather than his. He wondered if there was some big hot tub facility, down there overlooking the ocean. It did not seem impossible; the ocean here was cool, and if everything was economics, it could be seen as an investment. Maintaining the human infrastructure, so to speak.

      Back in the residence, his fellow guests were talking the day over. “I hate this kind of stuff,” said Sam.

      “We’re stuck with it,” Max said gloomily. “It’s join a cult or lose your job.”

      The others were not so pessimistic. “Maybe he’s just lonely,” Amy suggested.

      Sam and Max rolled their eyes and glanced toward the kitchen.

      “Maybe he always wanted to be a teacher,” Sally said.

      “Maybe he wants to keep Praxis growing ten percent per year,” George said, “full world or not.”

      Sam and Max nodded at this, and Elizabeth looked annoyed. “Maybe he wants to save the world!” she said.

      “Right,” Sam said, and Max and George snickered.

      “Maybe he’s got this room bugged,” Art said, which cut short the conversation like a guillotine.

      The days that followed were much like the first one. They sat in the conference room, and Fort circled them and talked through the mornings, sometimes coherently, sometimes not. One morning he spent three hours talking about feudalism—how it was the clearest political expression of primate dominance dynamics, how it had never really gone away, how transnational capitalism was feudalism writ large, how the aristocracy of the world had to figure out how to subsume capitalist growth within the steady-state stability of the feudal model. Another morning he talked about a caloric theory of value called eco-economics, apparently first worked out by early settlers on Mars; Sam and Max rolled their eyes at that news, while Fort droned on about Taneev and Tokareva equations, scribbling illegibly on a drawing board in the corner.

      But this pattern didn’t last, because a few days after their arrival a big swell came in from the south, and Fort cancelled their meetings and spent all his time surfing or (it turned out he did both) skimming over the waves in a birdsuit, which was a light broad-winged bodysuit, a flexible fly-by-wire hang-glider that translated the proper motions into successful flight. Most of the young scholarship winners joined him in the air, swooping around like Icaruses, and then dropping in and planing swiftly over the cushions of air before every breaking wave, air surfing just like the pelicans who had invented the sport.

      Art went out and thrashed around on a body board, enjoying the water which was chill, but not so much as to absolutely require a wetsuit. He hung out near the break that Joyce surfed, and chatted with her between sets, and found out that the other ancient kitchen workers were good friends of Fort’s, veterans of the first years of Praxis’s rise to prominence. The young scholars referred to them as the Eighteen Immortals. Some of the Eighteen were based at the camp, while others dropped by for a kind of ongoing reunion, conferring about problems, advising the current Praxis leadership on policy, running seminars and classes, and playing in the waves. Those who didn’t care for the water worked in the gardens.

      Art inspected the gardeners closely as he hiked back up to the compound. They worked in something resembling slow motion, talking to each other all the while. Currently the main task appeared to be harvesting the tortured apple bushes.

      The south swell subsided, and Fort reconvened Art’s group. One day the topic was Full World Business Opportunities, and Art began to see why he and his six fellows might have been chosen to attend: Amy and George worked in contraception, Sam and Max in industrial design, Sally and Elizabeth in agricultural technology, and he himself in resource recovery. They all worked in full world businesses already, and in the afternoons’ games they proved fairly good at designing new ones.

      Another day Fort proposed a game in which they solved the full world problem by returning to an empty world. They were to suppose the release of a plague vector which would kill everyone in the world who had not had the gerontological treatment. What would the pros and cons of such an action be?

      The group stared at their lecterns, nonplussed. Elizabeth declared that she wouldn’t play a game based on such a monstrous idea.

      “It is a monstrous idea,” Fort agreed. “But that doesn’t make it impossible. I hear things, you see. Conversations at certain levels. Among the leadership of the big transnationals, for instance, there are discussions. Arguments. You hear all kinds of ideas put out quite seriously, including some like this one. Everyone deplores them, and the subject changes. But no one claims that they are technically impossible. And some seem to think that they would solve certain problems that otherwise are unsolvable.”

      The group considered this thought unhappily. Art suggested that agricultural workers would be in short supply.

      Fort was looking out at the ocean. “That’s the fundamental problem with a collapse,” he said thoughtfully. “Once you start one, it’s hard to pick a point at which one can confidently say it will stop. Let’s go on.”

      And they did, rather subdued. They played Population Reduction, and given the alternative they had just contemplated, went at it with a certain amount of intensity. Each of them took a turn being Emperor of the World, as Fort put it, and outlined their plan in some detail.

      When it was Art’s turn, he said, “I would give everyone alive a birthright which entitled them to parent three-quarters of a child.”

      Everyone laughed, including Fort. But Art persevered. He explained that every pair of parents would thus have the right to bear a child and a half; after having one, they could either sell the right to the other half, or arrange to buy a