Alvin stared out toward the limits of his world. Twenty miles away, their details lost in distance, were the outer ramparts of the city, upon which seemed to rest the roof of the sky. There was nothing beyond them-nothing at all except the aching emptiness of the desert in which a man would soon go mad.

Then why did that emptiness call to him, as it called to no one else whom he had ever met? Alvin did not know. He stared out across the colored spires and battlements that now enclosed the whole dominion of mankind, as if seeking an answer to his question.

He did noL find it. But at that moment, as his heart yearned for the unattainable, he made his decision.

He knew now what he was going to do with life.

Jeserac was not very helpful, though he was not as uncooperative as Alvin had half expected. He had been asked such questions before in his long career as mentor, and did not believe that even a Unique like Alvin could produce many surprises or set him problems which he could not solve.

It was true that Alvin was beginning to show certain minor eccentricities of behavior, which might eventually need correction. He did not join as fully as he should in the incredibly elaborate social life of the city or in the fantasy worlds of his companions. He showed no great interest in the higher realms of thought, though at his age that was hardly surprising. More remarkable was his erratic love life; he could not be expected to form any relatively stable partnerships for at least a century, yet the brevity of his affairs was already famous. They were intense while they lasted-but not one of them had lasted for more than a few weeks. Alvin, it seemed, could interest himself thoroughly only in one thing at a time. There were times when he would join wholeheartedly in the erotic games of his companions, or disappear with the partner of his choice for several days. But once the mood had passed, there would be long spells when he seemed totally uninterested in what should have been a major occupation at his age. This was probably bad for him, and it was certainly bad for his discarded lovers, who wandered despondently around the city and took an unusually long time to find consolation elsewhere. Alystra, Jeserac had noticed, had now arrived at this unhappy stage.

It was not that Alvin was heartless or inconsiderate. In love, as in everything else, it seemed that he was searching for a goal that Diaspar could not provide.

None of these characteristics worried Jeserac. A Unique might be expected to behave in such a manner, and in due course Alvin would conform to the general pattern of the city. No single individual, however eccentric or brilliant, could affect the enormous inertia of a society that had remained virtually unchanged for over a billion years. Jeserac did not merely believe in stability; he could conceive of nothing else.

«The problem that worries you is a very old one,» he told Alvin, «but you will be surprised how many people take the world so much for granted that it never bothers them or even crosses their mind. It is true that the human race once occupied an infinitely greater space than this city. You have seen something of what Earth was like before the deserts came and the oceans vanished. Those records you are so fond of projecting are the earliest we possess; they are the only ones that show Earth as it was before the Invaders came. I do not imagine that many people have ever seen them; those limitless, open spaces are something we cannot bear to contemplate.

«And even Earth, of course, was only a grain of sand in the Galactic Empire. What the gulfs between the stars must have been like is a nightmare no sane man would try to imagine. Our ancestors crossed them at the dawn of history when they went out to build the Empire. They crossed them again for the last time when the Invaders drove them back to Earth.

«The legend is-and it is only a legend-that we made a pact with the Invaders. They could have the Universe if they needed it so badly, we would be content with the world on which we were born.

«We have kept that pact and forgotten the vain dreams of our childhood as you too will forget them, Alvin. The men who built this city, and designed the society that went with it, were lords of mind as well as matter. They put everything that the human race would ever need inside these walls-and then made sure that we would never leave them. Oh, the physical barriers are the least important ones. Perhaps there are routes that lead out of the city, but I do not think you would go along them for very far, even if you found them. And if you succeeded in the attempt, what good would it do? Your body would not last long in the desert, when the city could no longer protect or nourish it.»

«If there is a route out of the city,» said Alvin slowly, «then what is there to stop me from leaving?»

«That is a foolish question,» answered Jeserac. «I think you already know the answer.»

Jeserac was right, but not in the way he imagined. Alvin knew-or, rather, he had guessed. His companions had given him the answer, both in their waking life and in the dream adventures he had shared with them. They would never be able to leave Diaspar; what Jeserac did not know was that the compulsion which ruled their lives had no power over Alvin. Whether his uniqueness was due to accident or to an ancient design, he did not know, but this was one of its results. He wondered how many others he had yet to discover.

No one ever hurried in Diaspar, and this was a rule which even Alvin seldom broke. He considered the problem care-fully for several weeks, and spent much time searching the earliest of the city’s historical memories. For hours on end he would lie, supported by the impalpable arms of an anti-gravity field, while the hypnone projector opened his mind to the past. When the record was finished, the machine would blur and vanish-but still Alvin would lie staring into nothing-ness before he came back through the ages to meet reality again. He would see again the endless leagues of blue water, vaster than the land itself, rolling their waves against golden shores. His ears would ring with the boom of breakers stilled these billion years. He would remember the forests and the prairies, and the strange beasts that had once shared the world with Man.

Very few of these ancient records existed; it was generally accepted, though none knew the reason why, that somewhere between the coming of the Invaders and the building of Diaspar all memories of primitive times had been lost. So com-plete had been the obliteration that it was hard to believe it could have happened by accident alone. Mankind had lost its past, save for a few chronicles that might be wholly leg-endary. Before Diaspar there was simply the Dawn Ages. In that limbo were merged inextricably together the first men to tame fire and the first to release atomic energy-the first men to build a log canoe and the first to reach the stars. On the far side of this desert of time, they were all neighbors. Alvin had intended to make this trip alone once more, but solitude was not always something that could be arranged in Diaspar. He had barely left his room when he encountered Alystra, who made no attempt to pretend that her presence was accidental.

It had never occurred to Alvin that Alystra was beautiful, for he had never seen human ugliness. When beauty is universal, it loses its power to move the heart, and only its absence can produce any emotional effect.

For a moment Alvin was annoyed by the meeting, with its reminder of passions that no longer moved him. He was still too young and self-reliant to feel the need for any lasting relationships, and when the time came he might find it hard to make them. Even in his most intimate moments, the barrier of his uniqueness came between him and his lovers. For all his fully formed body, he was still a child and would re-main so for decades yet, while his companions one by one recalled the memories of their past lives and left him far behind. He had seen it happen before, and it made him wary of giving himself unreservedly to any other person. Even Alys-tra, who seemed so naive and artless now, would soon be-come a complex of memories and talents beyond his imagination.