He had taken his lead from me and managed a calm and literal reply. “No recorded children.”

“Incredible.” Kleeman was shaking her head. “That a man of your talents should be permitted to go so long without suitable mating…”

She looked at him hungrily, the way that I have seen McAndrew eye an untapped set of experimental data from out in the Halo. I could imagine how he had performed on the intellectual sections of the test.

“Come along,” she said at last, still eyeing McAndrew in a curiously intense and possessive way. “I would like to show you some of Home, and arrange for you to have living quarters for your use.”

“Don’t you want more details of why we are here?” burst out Mac. “We’ve come nearly two light-years to get to the Ark. ”

“You have been receiving our messages of the advances that we have made?” Kleeman’s manner had a vast self-confidence. “Then why should we be surprised when superior men and women from your system wish to come here? We are only surprised that it took you so long to develop a suitably efficient ship. Your vessel is new?”

“Very new.” I spoke before McAndrew could get a word in. Kleeman’s assumption that we were on the Ark to stay had ominous overtones. We needed to know more about the way the place functioned before we told her that we were planning only a brief visit.

“We have been developing the drive for our ship using results that parallel some of those found by your scientists,” I went on. I gave Mac a look that kept him quiet for a little while longer. “When we have finished with the entry preliminaries, Professor McAndrew would very much like to meet your physicists.”

She smiled serenely at him. “Of course. McAndrew, you should be part of our Council of Intellects. I do not know how high your position was back in your system, but I feel sure you have nothing as exalted — and as respected — as our Council. Well,” — she placed the two green cards she was holding in the pocket of her yellow smock — “there will be plenty of time to discuss induction to the Council when you have settled in here. The entry formalities are complete. Let me show you Home. There has never been anything like it in the whole of human history.”

Over the next four hours we followed Kleeman obediently through the interior of the Ark. McAndrew was itching to locate his fellow-physicists, but he knew he was at the mercy of Kleeman’s decisions. From our first meeting with others on the Ark, there was no doubt who was the boss there.

How can I describe the interior of the Ark? Imagine a free-space beehive, full of hard-working bees that had retained an element of independence of action. Everyone on the Ark of Massingham seemed industrious, cooperative, and intelligent. But they were missing a dimension, the touch of orneriness and unpredictability that you would find on Luna or on Titan. Nobody was cursing, nobody was irrational. Kleeman guided us through a clean, slightly dull Utopia.

The technology of the Ark was simpler to evaluate. Despite the immense pride with which Kleeman showed off every item of development, they were half a century behind us. The sprawling, overcrowded chaos of Earth was hard to live with, but it provided a constant pressure towards innovation. New inventions come fast when ten billion people are there to push you to new ideas. In those terms, life on the Ark was spacious and leisurely. The colony had constructed its network of interlocking tunnels to a point where it would take months to explore all the passages and corridors, but they were nowhere near exhausting their available space and resources.

“How many people would the Ark hold?” I asked McAndrew as we trailed along behind Kleeman. It would have taken only a minute or two to work it out for myself, but you get lazy when you live for a while with a born calculator.

“If they don’t use the interior material to extend the surface of the Ark?” he said. “Give them the same room as we’d allow on Earth, six meters by six meters by two meters. They could hold nearly sixty million. Halve that, maybe, to allow for recycling and maintenance equipment.”

“But that is not our aim,” said Kleeman. She had overheard my question. “We are stabilized at ten thousand. We are not like the fools back on Earth. Quality is our aim, not mindless numbers.”

She had that tone in her voice again, the one that had made me instinctively avoid the question of how long we would be staying on the Ark. Heredity is a potent influence. I couldn’t speak about Jules Massingham, the founder of this Ark, but his daughter was a fanatic. I have seen others like her over the years. Nothing would be allowed to interfere with the prime objective: build the Ark ’s population on sound eugenic principles. Kleeman was polite to me — I was “prime stock” — but she had her eye mainly on McAndrew. He would be a wonderful addition to her available gene pool.

Well, the lady had taste. I shared some of that attitude myself. “Father unknown” was literally true and Mac and I had not chosen to elaborate. Our daughter had rights, too, and Jan’s parentage would not be officially known unless she chose after puberty to take the chromosome matching tests.

Over the next six days, McAndrew and I worked our way into the life pattern aboard the Ark. The place ran like a clock, everything according to a schedule and everything in the right position. I had a good deal of leisure time, which I used to explore the less-popular corridors, up near the Hub. McAndrew was still obsessed with his search for physicists.

“No sense here,” he growled to me, after a meal in the central dining area out on the Ark ’s equator. As I had guessed, effective gravity there was about a tenth of a gee. “I’ve spoken to a couple of dozen of their scientists. There’s not one of them would last a week at the Institute. Muddled minds and bad experiments.”

He was angry. Usually McAndrew was polite to all scientists, even ones who couldn’t understand what he was doing, still less add to it.

“Have you seen them all? Maybe Kleeman is keeping some of them from us.”

“I’ve had that thought. She’s talked to me every day about the Council of Intellects, and I’ve seen some of the things they’ve produced. But I’ve yet to meet one of them, in person.” He shrugged, and rubbed at his sandy, receding hairline. “After we’ve slept I’m going to try another tack. There’s a schoolroom over on the other side of the Ark, where I gather Kleeman keeps people who don’t seem quite to fit into her ideas. Want to take a look there with me, tomorrow?”

“Maybe. I’m wondering what Kleeman has in mind for me. I think I know her plans for you, she sees you as another of her senior brains.” I saw the woman herself approaching us across the wide room, with its gently curving floor. “You’d like it, I suspect. It seems to be like the Institute, but members of the Council have a lot more prestige.”

I had immediate proof that I was right. Kleeman seemed to have made up her mind. “We need a commitment from you now, McAndrew,” she said. “There is a coming vacancy on the Council. You are the best person to fill it.”

McAndrew looked flattered but uncomfortable. The trouble was, it really did interest him, I could tell that. The idea of a top-level brains trust had appeal.

“All right,” he said after a few moments. He looked at me, and I could tell what he was thinking. If we were going to be on our way back home soon, it would do no harm to help the Ark while he was here. They could use all the help available.

Kleeman clapped her hands together softly; plump white hands that pointed out her high position — most people on the Ark had manual duties to keep the place running, with strict duty rosters.

“Wonderful! I will plan for your induction tomorrow. Let me make the announcement tonight, and we can speed up the proceedings for the outgoing member.”