for the mind to contemplate.
It was hard to believe that they had now been flung out of the Solar System at a speed which unless it were checked would soon take them through the heart of the Galaxy and into the greater emptiness beyond. Neither Alvin nor Hilvar could conceive the real immensity of their journey; the great sagas of exploration had completely changed Man's outlook toward the Universe and even now, millions of centuries later, the ancient traditions had not wholly died. There had once been a ship, legend whispered, that had circumnavigated the Cosmos between the rising and the setting of the sun. The billions of miles between the stars meant nothing before such speeds. To Alvin this voyage was very little greater, and perhaps less dangerous, than his first journey to Lys.
It was Hilvar who voiced both their thoughts as the Seven Suns slowly brightened ahead.
"Alvin," he remarked, "that formation can't possibly be natural."
The other nodded.
"I've thought that for years, but it still seems fantastic."
"The system may not have been built by Man," agreed Hilvar, "but intelligence must have created it. Nature could never have formed that perfect circle of stars, all equally brilliant. And there's nothing else in the visible Universe like the Central Sun."
"Why should such a thing have been made, then?"
"Oh, I can think of many reasons. Perhaps it's a signal, so that any strange ship entering our Universe will know where to look for life. Perhaps it marks the center of galactic administration. Or perhaps-and somehow I feel that this is the real explanation-it's simply the greatest of all works of art. But it's foolish to speculate now. In a few hours we shall know the truth."
"We shall know the truth." Perhaps, thought Alvin-but how much of it shall we ever know? It seemed strange that now, while he was leaving Diaspar, and indeed Earth itself, at a speed beyond all comprehension, his mind should turn once more to the mystery of his origin. Yet perhaps it was not so surprising; he had learned many things since he had first arrived in Lys, but until now he had not had a single moment for quiet reflection.
There was nothing he could do now but sit and wait; his immediate future was controlled by the wonderful machine -surely one of the supreme engineering achievements of all time-that was now carrying him into the heart of the Universe. Now was the moment for thought and reflection, whether he wished it or not. But first he would tell Hilvar all that had happened to him since their hasty parting only two days before.
Hilvar absorbed the tale without comment and without asking for any explanations; he seemed to understand at once everything that Alvin described, and showed no signs of surprise even when he heard of the meeting with the Central Computer and the operation it had performed upon the robot's mind. It was not that he was incapable of wonder, but that the history of the past was full of marvels that could match anything in Alvin's story.
"It's obvious," he said, when Alvin had finished talking, "that the Central Computer must have received special instructions regarding you when it was built. By now, you must have guessed why."
"I think so. Khedron gave me part of the answer when he explained how the men who designed Diaspar had taken steps to prevent it becoming decadent."
"Do you think you-and the other Uniques before you are part of the social mechanism which prevents complete stagnation? So that whereas the Jesters are short-term correcting factors, you and your kind are long-term ones?"
Hilvar had expressed the idea better than Alvin could, yet this was not exactly what he had in mind.
"I believe the truth is more complicated than that. It almost looks as if there was a conflict of opinion when the city was built, between those who wanted to shut it off completely from the outside world, and those who wanted to maintain some contacts. The first faction won, but the others did not admit defeat. I think Yarlan Zey must have been one of their leaders, but he was not powerful enough to act openly. He did his best, by leaving the subway in existence and by insuring that at long intervals someone would come out of the Hall of Creation who did not share the fears of all his fellow men, In fact, I wonder-" Alvin paused, and his eyes veiled with thought so that for a moment he