“Have you seen the riverine canyons?” she asked.

“Yes, I saw Nirgal Vallis. Remarkable how satisfying it was to see water down at its bottom. So apt.”

“I didn’t know there was so much tundra out here.”

Tundra was the dominant ecology for much of the southern highlands, he told her. Tundra and desert. In the tundra, fines were fixed very effectively to the ground; no wind could lift mud, or quicksand, of which there was a good quantity, making it dangerous to travel in certain regions. But in the deserts the powerful winds ripped great quantities of dust into the sky, cooling temperatures while they darkened the day, and causing problems where they landed, as they had for Nirgal. Suddenly curious, he said, “Have you ever met Nirgal?”

The sandstorms these days were nothing like the long-forgotten Great Storm of course, but still a factor that had to be considered. Desert pavement formed by microbacteria was one very promising solution, though it tended to fix only the top centimeter of deposits, and if the wind tore the edge of the pavement, what was underneath was then free to be borne away. Not an easy problem. Dust storms would be with them for centuries.

Still, an active hydrosphere. Meaning life everywhere.

Bao’s mother died in a small plane crash, and Bao as the youngest daughter had to go home and take care of things, including possession of the family home. Ultimogeniture in action, modeled on the Hopi matriarchy, he was told. Bao wasn’t sure when she would be back; there was even a chance she wouldn’t be. She was matter-of-fact about it, it was just something that had to be done. Withdrawn already into an internal world. Sax could only wave good-bye to her and walk back to his room, shaking his head. They would understand the fundamental laws of the universe before they had even the slightest handle on society. A particularly obdurate subject of study. He called Michel on screen and expressed something like this, and Michel said, “It’s because culture keeps progressing.”

Sax thought he could see what Michel meant — there were rapid changes in attitudes to many things. Werteswandel, as Bela called it, mutation of values. But they still lived in a society struggling with archaisms of all sorts. Primates banding into tribes, guarding a territory, praying to a god like a cartoon parent… “Sometimes I don’t think there’s been any progress at all,” he said, feeling strangely disconsolate.

“But Sax,” Michel protested, “right here on Mars we have seen both patriarchy and property brought to an end. It’s one of the greatest achievements in human history.”

“If true.”

“Don’t you think women have as much power as men now?”

“As far as I can tell.”

“Perhaps even more, when it comes to reproduction.”

“That would make sense.”

“And the land is in the shared stewardship of everyone.

We still own personal items as property, but land as property has never happened here. That’s a new social reality, we struggle with it every day.”

So they did. And Sax remembered how bitter the conflicts had been in the old days, when property and capital had been the order of the day. Yes, perhaps it was true: patriarchy and property were in the process of being dismantled. At least on Mars, at least for now. As with string theory, it might take a long time to work it into any proper state. After all Sax himself, who had no prejudices whatsoever, had been amazed to see a woman mathematician at work. Or, to be more precise, a woman genius. By whom he had been promptly hypnotized, so to speak, along with every other man in the theory group — to the point of being rendered quite distraught by her departure. Uneasily he said, “On Earth people seem to be fighting just as much as before.”

Even Michel had to admit it. “Population pressures,” he said, trying to wave them away. “There are too many people down there, and more all the time. You saw what it was like during our visit. As long as Earth is in that situation, Mars is under threat. And so we fight up here too.”

Sax took the point. In a way it was comforting; human behavior not as irreducibly evil or stupid, but as responding, semirationally, to a given historical situation, a danger. Seizing what one could, with the notion that there might not be enough for all; doing everything possible to protect one’s offspring; which of course endangered all offspring, by the aggregate of individual selfish actions. But at least it could be called an attempt at reason, a first approximation.

“It’s not as bad as it was, anyway,” Michel was saying. “Even on Earth people are having far fewer children. And they’re reorganizing into collectives pretty well, considering the flood and all the trouble that preceded it. A lot of new social movements down there, a lot of them inspired by what we’re doing here. And by what Nirgal does. They’re still watching him and listening to him, even when Tie doesn’t speak. What he said during our visit there is still having a big effect.”

“I believe it.”

“Well, there you are! It’s getting better, you have to admit it. And when the longevity treatments stop working, there will come a balance of births and deaths.”

“We’ll hit that time soon,” Sax predicted glumly.

“Why do you say so?”

“Signs of it cropping up. People dying from one thing or other. Senescence is not a simple matter. Staying alive when senescence should have kicked in — it’s a wonder we’ve done as much as we have. There’s probably a purpose in senescence. Avoiding overpopulation, perhaps. Making room for new genetic material.”

“That bodes poorly for us.”

“We’re already over two hundred percent the old average lifetime.”

“Granted, but even so. One doesn’t want it to end just because of that.”

“No. But we have to focus on the moment. Speaking of which, why don’t you come out into the field with me? I’ll be as upbeat as you want out there. It’s very interesting.”

“I’ll try to free up some time. I’ve got a lot of clients.”

“You’ve got a lot of free time. You’ll see.”

In this particular moment, the sun was high. Rounded white clouds were piling up in the air overhead, forming great masses that would never come again, though at the moment they were as solid as marble, and darkening at their bottoms. Cumulonimbus. He was standing on Da Vinci Peninsula’s western cliff again, looking across Shalbatana Fjord to the cliff edging the east side of Lunae Planum. Behind him rose the flat-topped hill that was the rim of Da Vinci Crater. Home base. He had lived there a long time now. These days their co-op was making many of the satellites being put up into orbit, and the boosters as well, in collaboration with Spencer’s lab in Odessa, and a great number of other places. A Mondragon-style cooperative, operating the ring of labs and homes in the rim, and the fields and lake filling the crater floor. Some of them chafed at restrictions imposed by the courts on projects they had in mind, involving new power plants that would put out too much heat. In the last few years the GEC had been issuing K rations, as they were called, giving communities the right to add some fraction of a degree Kelvin to the global warming. Some Red communities were doing their best to get assigned K rations and then not use them. This action, along with ongoing incidences of ecotage, kept the global temperature from rising very fast no matter what other communities did. Or so the other communities argued. But the ecocourts were still parsimonious with the K rations. Cases were judged by a provincial ecocourt, then the judgment was approved by the GEC, and that was it: no appeals, unless you could get a petition signed by fifty other communities, and even then the appeal was only dropped into the morass of the global legislature, where its fate was up to the undisciplined crowd in the duma.

Slow progress. Just as well. With the global average temperatures above freezing, Sax was content. Without the constraint of the GEC, things could easily get too warm. No, he was in no further hurry. He had become an advocate of stabilization.