The Paradox of the Sets. Brian Stableford

altitude of the tree line. I continued up the slope for a couple of frames, and was getting quite exhausted by the energy-sapping toil I could feel in my imagination.

      Then I came to a much steeper upslope which reared to a narrow ridge and then plummeted again into a great elliptical bowl—an egg-shaped crater. Here, because of the high walls, there was protection from wind, and the inside of the crater had taken full advantage of that fact. Here, as nowhere else, there was a truly rich flora—and no doubt fauna too. The long axis of the crater was about ten miles in extent—or so I estimated, because it ran slantwise across the track, and the corner of it was chopped off—while the shorter axis was about seven.

      “Look at that!” I said.

      Karen looked at it, then referred back to the computer scan we had carried out on the pictures.

      “The computer sorted that one out,” she said, as if that made it immediately uninteresting.

      “It’s a funny-looking crater,” I said. “And it’s in a funny place. It’s not on top of a mountain—in fact it’s on the lower slopes. That long hill continues from the other ridge, up and up and up. And look at these lines at the northern wall. They must be fissures of some kind. These blurry wisps here and there might be vapor being blown out of them. And what are these, half-hidden by the trees?”

      Karen got down on her hands and knees to look, but realized immediately how stupid we must have looked. She picked up the two frames containing most of the crater and put them back on the table where we could inspect them in a civilized manner. I checked the serial numbers and started rifling through the piles in search of the missing bit of the crater.

      “They look to me,” said Karen, “rather like circular tents. But I wouldn’t swear to it. No one would. And over here might be the roof of a cabin. But we’re at the limits of resolution here and my eye is going crazy trying to make it out.”

      “If we had an overlapping frame,” I said, “we could rig up a stereoscope and get a 3-D image.”

      She shook her head. “We weren’t taking them that quickly,” she said. “These are just broken bits of what was actually a much larger image.”

      “I think you’re right about the tents and the cabin,” I said, after long perusal and due consideration. “Someone’s in the crater. Mme. Levasseur didn’t mention that. If she knows about it, then the crater might be the point by which she set our course and selected the area for scanning. If she doesn’t know....”

      “...it might be what she’s looking for.”

      I pondered. “What kind of crater do you think that is?” I asked her.

      “Volcanic,” she answered. “What else?”

      “Elliptical in shape? On the lower slopes of a mountain?”

      She shrugged. “What both of us know about vulcanology could be written on the back of a postage stamp,” she pointed out. Which was true enough.

      She picked up another print from the floor and showed it to me. This was the one which included the actual mountain peak—the middle one of the three we could see through the scanner. There was no mistaking that one. It was volcanic all right, though seemingly long extinct. It had a big, deep cone which had solidified a long time ago. This crater too was filled with vegetation now, though it was by no means so rich as that in the egg-shaped crater, being several thousand feet higher up.

      “So okay,” I said. “Way back when there was a double blast, with fire belching out of the side of the mountain as well as the cone. I guess volcanoes aren’t any tidier than the rest of nature.”

      “It could hardly be the crater itself that Mme. Levasseur is looking for,” said Karen, picking up another thread. “It’s on the survey team’s maps, and it’s clearly visible from the slopes of the three peaks we can see. But if the people encamped in it are....”

      She stopped then.

      “Escaped criminals?” I suggested. “Leaders of the revolution? Escaped slaves?”

      We exchanged a slightly significant glance. The last one was hardly likely to be true, but it did touch upon a point we’d both considered privately. It takes a big workforce to build thousands of miles of road, the colony had spread out to occupy all the lands that the Sets had formerly possessed, and the Sets were noted in the survey reports as being conspicuously docile. Mme. Levasseur had been very cagey about the population and the aliens—but if you were a colony who had worked wonders by enslaving the indigenes, would you brag about it to the first mission from the supposedly high-minded United Nations of Earth?

      “That crater’s only about fifty miles away,” I said. “I could walk it in a day.”

      “There isn’t a highway,” Karen pointed out.

      “No, but those slopes are very shallow. And there’s no obstruction worthy of the name. With the day here being as long as it is, and this being summer hereabouts, there must be nearly twenty hours daylight in our terms. I could do it.”

      “Fifty miles is a hell of a long way,” she said.

      “I’m fit. And I’m also interested. If that’s Dr. Livingstone I’d love to play Stanley.”

      “Sure,” she said. “And I’m She-who-must-be-Obeyed.”

      “You have to stay with the ship anyhow,” I pointed out. “More repairs. Anyhow, it’s less than fifty. Maybe only forty. Depends how far off the edge of this last print we are. It can’t be all that far—I can see that peak clearly enough and that’s a good twenty miles farther on.”

      “You can see a long way in the mountains,” she said, “when you’re looking at other mountains.”

      I eyed the clock speculatively. “I can sleep most of the day,” I said. “Then put the idea to Nathan late this afternoon. We could make an early start, assuming he wants to come too.”

      She shrugged. I couldn’t tell whether it was because she thought it was a dumb idea or because she wouldn’t be able to come along. “Mme. Levasseur isn’t going to like it,” she said, ominously.

      “I’m sure Nathan can put it to her in a way that makes it very difficult for her to forbid it. Besides which, she can’t forbid it without giving us a reason, and that would mean giving up her policy of playing the cards so close to her chest.”

      I paused, then added: “One of these days we’ll land on a world where everything is nice and straightforward.”

      “Hardly,” she replied. “Our next stop’s the least straightforward place in the universe.”

      CHAPTER FOUR

      It was, of course, a good idea in principle. The words “fifty miles” roll off one’s tongue so lightly, and the words “less than fifty miles” have a positively enthusiastic tone about them. But our mouths have more ambition than our feet. Words, whatever common parlance may say, speak a great deal more loudly than actions. By the time we’d walked for three hours the distance still to be covered no longer seemed like an easy prospect. It seemed to have stretched to mammoth proportions.

      It had been easy enough to talk Nathan into coming along. He was exasperated by the annoyingly secretive Helene Levasseur, who was on her way to “find” us and to “rescue” us, but who was in the meantime taking pains to see that nothing disturbed our blissful ignorance of the way things were on Geb. Nathan had tackled her with the information that there seemed to be people up here in the mountains, camped in an elliptical crater a mere day’s walk away. She admitted that she’d known of the man’s presence somewhere in the vicinity—she gave his name as Johann Gley and spoke as if there were only one of him—but she advised us to stay away from him, on what seemed to be the rather slender excuse that he was not known for his sociability.

      When Nathan made it clear that we intended to make contact she was obviously peeved but merely repeated that it wasn’t a good idea. She