because it gave him a background and made him an authentic product of the 24th. The body of the real Mallansohn was never recovered.
"In the remainder of his life, he cherished his generator and cooperated with the Institute scientists in duplicating it. He dared do no more than that. He could not teach them the Lefebvre equations without outlining three Centuries of mathematical development that was to come. He could not, dared not hint at his true origin. He dared not do more than the real Vikkor Mallansohn had, to his knowledge, done.
"The men who worked with him were frustrated to find a man who could perform so brilliantly and yet was unable to explain the whys of his performance. And he himself was frustrated too, because he foresaw, without in any way being able to quicken, the work that would lead, step by step, to the classic experiments of Jan Verdeer, and how from that the great Antoine Lefebvre would construct the basic equations of Reality. And how, after that, Eternity would be constructed.
"It was only toward the end of his long life that Cooper, staring into a Pacific sunset (he describes the scene in some detail in his memoir) came to the great realization that he was Vikkor Mallansohn; he was not a substitute but the man himself. The name might not be his, but the man history called Mallansohn was really Brinsley Sheridan Cooper.
"Fired with that thought, and with all that implied, anxious that the process of establishing Eternity be somehow quickened, improved, and made more secure, he wrote his memoir and placed it in a cube of Time-stasis in the living room of his house.
"And so the circle was closed. Cooper-Mallansohn's intentions in writing the memoir were, of course, disregarded. Cooper must go through his life exactly as he had gone through it. Primitive Reality allows of no changes. At this moment in physiotime, the Cooper you know is unaware of what lies ahead of him. He believes he is only to instruct Mallansohn and to return. He will continue to believe so until the years teach him differently and he sits down to write his memoir.
"The intention of the circle in Time is to establish the knowledge of Time-travel and of the nature of Reality, to build Eternity, ahead of its natural Time. Left to itself, mankind would not have learned the truth about Time before their technological advances in other directions had made racial suicide inevitable."
Harlan listened intently, caught up in the vision of a mighty circle in Time, closed upon itself, and traversing Eternity in part of its course. He came as close to forgetting Noys, for the moment, as he ever could.
He asked, "Then you knew all along everything you were to do, everything I was to do, everything I have done."
Twissell, who seemed lost in his own telling of the tale, his eyes peering through a haze of bluish tobacco smoke, came slowly to life. His old, wise eyes fixed themselves on Harlan and he said reproachfully, "No, of course not. There was a lapse of decades of physiotime between Cooper's stay in Eternity and the moment when he wrote his memoir. He could remember only so much, and only what he himself had witnessed. You should realize that."
Twissell sighed and he drew a gnarled finger through a line of updrafting smoke, breaking it into little turbulent swirls. "It worked itself out. First, I was found and brought to Eternity. When, in the fullness of physiotime, I became a Senior Computer, I was given the memoir and placed in charge. I had been described as in charge, so I was placed in charge. Again in the fullness of physiotime, you appeared in the changing of a Reality (we had watched your earlier analogues carefully), and then Cooper.
"I filled in the details by using my common sense and the services of the Computaplex. How carefully, for instance, we instructed Educator Yarrow in his part while betraying none of the significant truth. How carefully, in his turn, he stimulated your interest in the Primitive.
"How carefully we had had to keep Cooper from learning anything he did not prove he had learned by reference in the memoir." Twissell smiled sadly. "Sennor amuses himself with matters such as this. He calls it the reversal of cause and effect. Knowing the effect, one adjusts the cause. Fortunately, I am not the cobweb spinner Sennor is.
"I was pleased, boy, to find you so excellent an Observer and