“That was meant to be a threat.”

            “I took it literally. Forgive me. I must have your help.”

            It came to that. Harlan’s help must be had. Was he mad? Was Harlan mad? Did madness have meaning? Or anything at all, for that matter?

            The Council needed his help. For that help they would promise him anything. Noÿs. Computership. What would they not promise him? And when his help was done with, what would he get? He would not be fooled a second time.

            “No!” he said.

            “You’ll have Noÿs.”

            “You mean the Council will be willing to break the laws of Eternity once the danger is safely gone? I don’t believe it.” How could the danger safely be passed, a sane scrap of his mind demanded. What was this all about?

            “The Council will never know.”

            “Would you be willing to break the laws? You’re the ideal Eternal. With the danger gone, you would obey the law. You couldn’t act otherwise.”

            Twissell reddened blotchily, high on each cheekbone. From the old face all shrewdness and strength drained away. There was left only a strange sorrow.

            “I will keep my word to you and break the law,” said Twissell, “for a reason you don’t imagine. I don’t know how much time is left us before Eternity disappears. It could be hours; it could be months. But I have spent so much time in the hope of bringing you to reason that I will spend a little more. Will you listen to me? Please?”

            Harlan hesitated. Then, out of a conviction of the uselessness of all things as much as out of anything else, said wearily, “Go on.”

            I have heard (began Twissell} that I was born old, that I cut my teeth on a Micro-Computaplex, that I keep my hand computer in a special pocket of my pajamas when I sleep, that my brain is made up of little force-relays in endless parallel hookups and that each corpuscle of my blood is a microscopic spatio-temporal chart floating in computer oil.

            All these stories come to me eventually, and I think I must be a little proud of them. Maybe I go around believing them a bit. It’s a foolish thing for an old man to do, but it makes life a little easier.

            Does that surprise you? That I must find a way to make life easier? I, Senior Computer Twissell, senior member of the Allwhen Council?

            Maybe that’s why I smoke. Ever think of that? I have to have a reason, you know. Eternity is essentially an unsmoking society, and most of Time is, too. I’ve thought of that often. I sometimes think it’s a rebellion against Eternity. Something to take the place of a greater rebellion that failed...

            No, it’s all right. A tear or two won’t hurt me, and it isn’t pretense, believe me. It’s just that I haven’t thought about this for a long time. It isn’t pleasant.

            It involved a woman, of course, as your affair did. That’s not coincidence. It’s almost inevitable, if you stop to think of it. An Eternal, who must sell the normal satisfactions of family life for a handful of perforations on foil, is ripe for infection. That’s one of the reasons Eternity must take the precautions it does. And, apparently, that’s also why Eternals are so ingenious in evading the precautions once in a while.

            I remember my woman. It’s foolish of me to do so, perhaps. I can’t remember anything else about that physiotime. My old colleagues are only names in the record books; the Changes I supervised--all but one--are only items in the Computaplex memory pools. I remember her, though, very well. Perhaps you can understand that.

            I had had a long-standing request for liaison in the books; and after I achieved status as a Junior Computer, she was assigned to me. She was a girl of this very Century, the 575th. I didn’t see her until after the assignment, of course. She was intelligent and kind. Not beautiful or even pretty, but then, even when young (yes, I was young, never mind the myths) I was not noted for my own looks. We were well suited to one another by temperament, she and I, and if I were a Timed man, r would have been proud to have her as my wife. I told her that many times. I believe it pleased her. I know it was the truth. Not all Eternals, who must take their women as and how Computing permits, are that fortunate.

            In that particular Reality, she was to die young, of course, and none of her analogues was available for liaison. At first, I took that philosophically. After all, it was her short lifetime which made it possible for her to live with me without deleteriously affecting Reality.

            I am ashamed of that now, of the fact that I was glad she had a short time to live. Just at first, that is. Just at first.

            I visited her as often as spatio-temporal charting allowed. I squeezed every minute out of it, giving up meals and sleep when necessary, shifting my labor load shamelessly whenever I could. Her amiability passed the heights of my expectations, and I was in love. I put it bluntly. My experience of love is very small, and understanding it through Observation in Time is a shaky matter. As far as my understanding went, however, I was in love.

            What began as the satisfaction of an emotional and physical need became a great deal more. Her imminent death stopped being a convenience and became a calamity. I Life-Plotted her. I didn’t go to the Life-Plotting departments, either. I did it myself. That surprises you, I imagine. It was a misdemeanor, but it was nothing compared to the crimes I committed later.

            Yes, I, Laban Twissell, Senior Computer Twissell.

            Three separate times, a point in physiotime came and passed, during which some simple action of my own might have altered her personal Reality. Naturally, I knew that no such personally motivated Change could possibly be authorized by the Council. Still, I began to feel personally responsible for her death. That was part of my motivation later on, you see.

            She became pregnant. I took no action, though I should have. I had worked her Life-Plot, modified to include her relationship with me, and I knew pregnancy to be a high-probability consequence. As you mayor may not know, Timed women are occasionally made pregnant by Eternals despite precautions. It is not unheard of. Still, since no Eternal may have a child, such pregnancies as do occur are ended painlessly and safely. There are many methods.

            My Life-Plotting had indicated she would die before delivery, so I took no precautions. She was happy in her pregnancy and I wanted her to remain so. So I only watched and tried to smile when she told me she could feel life stirring within her.

            But then something happened. She gave birth prematurely

            I don’t wonder you look that way. I had a child. A real child of my own. You’ll find no other Eternal, perhaps, who can say that. That was more than a misdemeanor. That was a serious felony; but it was still nothing.

            I hadn’t expected it. Birth and its problems were an aspect of life with which I had had little experience.

            I went back to the Life-Plot in panic and found the living child, in an alternate solution to a low-probability forklet I had overlooked. A professional Life-Plotter would not have overlooked it and I had done wrong to trust my own abilities that far.

            But what could I do now?

            I couldn’t kill the child. The mother had two weeks to live. Let the child live with her till then, I thought. Two weeks of happiness is not an exorbitant gift to ask.

            The mother died, as foreseen, and in the manner foreseen. I sat in her room, for all the time permitted by the spatiotemporal chart, aching with a sorrow all the keener for my having waited for death, in full knowledge, for over a year. In my arms, I held my son and hers.

            --Yes, I let it live. Why do you cry out so? Are you going to condemn me?

            You cannot know what it means to hold a little atom of your own life in your arms. I may have a Computaplex for nerves and spatio-temporal charts for a bloodstream, but I do know.

            I let it live. I committed that crime, too. I put it in the charge of an appropriate organization and returned when I could (in strict temporal sequence, held even with physiotime) to make necessary payments and to watch the boy grow.

            Two years went by that way. Periodically, I checked the boy’s Life-Plot (I was used to breaking that particular rule, by now) and was pleased to find that there were no signs of deleterious effects on the then-current Reality at probability levels over 0.0001. The boy learned to walk and mispronounced a few words. He was not taught to call me “daddy.” Whatever speculations the Timed people of the child-care institution might have made concerning me I don’t know. They took their money and said nothing.

            Then, when the two years had passed, the necessities of a Change that included the 575th at one wing was brought up before the Allwhen Council. I, having been lately promoted to Assistant Computer, was placed in charge. It was the first Change ever left to my sole supervision.

            I was proud, of course, but also apprehensive. My son was an intruder in the Reality. He could scarcely be expected to have analogues. Thought of his passage into nonexistence saddened me.

            I worked at the Change and I flatter myself even yet that I did a flawless job. My first one. But I succumbed to a temptation. I succumbed to it all the more easily because it was becoming an old story now for me. I was a hardened criminal, a habitué of crime. I worked out a new Life-Plot for my son under the new Reality, certain of what I would find.

            But then for twenty-four hours, without eating or sleeping, I sat in my office, striving with the completed Life-Plot, tearing at it in a despairing effort to find an error.

            There was no error.

            The next day, holding back my solution to the Change, I worked out a spatio-temporal chart, using rough methods of approximation (after all, the Reality was not to last long) and entered Time at a point more than thirty years up when from the birth of my child.

            He was thirty-four years old, as old as I myself. I introduced myself as a distant relation, making use of my knowledge of his mother’s family, to do so. He had no knowledge of his father, no memory of my visits to him in his infancy.

            He was an aeronautical engineer. The 575th was expert in half a dozen varieties of air travel (as it still is in the current Reality), and my son was a happy and successful member of his society. He was married to an ardently enamored girl, but would have no children. Nor would the girl have married at all “in the Reality in which my son had not existed. I had known that from the beginning. I had known there would be no deleterious affect on Reality. Otherwise, I might not nave found it in my heart to let the boy live. I am not completely abandoned.

            I spent the day with my son. I spoke to him formally, smiled politely, took my leave coolly when the spatio-temporal chart dictated. But underneath all that, I watched and absorbed every action, filling myself with him, and trying to live one day at least out of a Reality that the next day (by physiotime) would no longer have existed.

            How I longed to visit my wife one last time, too, during that portion of Time in which she lived, but I had used every second that had been available to me. I dared not even enter Time to see her, unseen.

            I returned to Eternity and spent one last horrible night wrestling futilely against what must be. The next morning I handed in my computations together with my recommendations for Change.

            Twissell’s voice had lowered to a whisper and now it stopped. He sat there with his shoulders bent, his eyes fixed on the floor between his knees, and his fingers twisting slowly into and out of a knotted clasp.

            Harlan, waiting vainly for another sentence out of the old man, cleared his throat. He found himself pitying the man, pitying him despite the many crimes he had committed. He said, “And that’s all?”

            Twissell whispered, “No, the worst--the worst--An analogue of my son did exist. In the new Reality, he existed--as a paraplegic from the age of four. Forty-two years in bed, under circumstances that barred me from arranging to have the nerve-regenerating techniques of the 900’s applied to his case, or even for arranging to have his life ended painlessly.

            “That new Reality still exists. My son is still out there in the appropriate portion of the Century. I did that to him. It was my mind and my Computaplex that discovered this new life for him, and my word that ordered the Change. I had committed a number of crimes for his sake and for his mother’s, but that one last deed, though strictly in accordance with my oath as an Eternal, has always seemed to me to be my great crime, the crime.”

            There was nothing to say, and Harlan said nothing.

            Twissell said, “But you see now why I understand your case, why I will be willing to let you have your girl. It would not harm Eternity and, in a way, it would be expiation for my crime.”

            And Harlan believed. All in one change of mind, he believed!

            Harlan sank to his knees and lifted his clenched fists to his temples. He bent his head and rocked slowly as savage despair beat through him.

            He had thrown Eternity away, and lost Noÿs--when, except for his Samson-smash, he might have saved one and kept the other.

            15. Search through the Primitive

            TWISSELL WAS shaking Harlan’s shoulders. The old man’s voice urgently called his name.

            “Harlan! Harlan! For Time’s sake, man.”

            Harlan emerged only slowly from the slough. “What are we to do?”

            “Certainly not this. Not despair. To begin with, listen to me. Forget your Technician’s view of Eternity and look at it through a Computer’s eyes. The view is more sophisticated. When you alter something in Time and create a Reality Change, the Change may take place at once. Why should that be?”

            Harlan said shakily, “Because your alteration has made the Change inevitable?”

            “Has it? You could go back and reverse your alteration, couldn’t you?”

            “I suppose so. I never did, though. Or anyone that I heard of.”

            “Right. There is no intention of reversing an alteration, so it goes through as planned. But here we have something else. An unintentional alteration. You sent Cooper into the wrong Century and now I firmly intend to reverse that alteration and bring Cooper back here.”

            “For Time’s sake, how?”

            “I’m not sure yet, but there must be a way. If there were no way, the alteration would be irreversible; Change would come at once. But Change has not come. We are still in the Reality of the Mallansohn memoir. That means the alteration is reversible and will be reversed.”

            “What?” Harlan’s nightmare was expanding and swirling, growing murkier and more engulfing.

            “There must be some way of knitting the circle in Time together again and our ability to find the way to do it must be a high-probability affair. As long as our Reality exists, we can be certain that the solution remains high-probability. If at any moment, you or I make the wrong decision, if the probability of healing the circle falls below some crucial magnitude, Eternity disappears. Do you understand?”

            Harlan was not sure that he did. He wasn’t trying very hard. Slowly he got to his feet and stumbled his way into a chair.

            “You mean we can get Cooper back--”

            “And send him to the right place, yes. Catch him at the moment he leaves the kettle and he may end up in his proper place in the 24th no more than a few physiohours older; physiodays, at the most. It would be an alteration, of course, but undoubtedly not enough of one. Reality would be rocked, boy, but not upset.”

            “But how do we get him?”

            “We know there’s a way, or Eternity wouldn’t be existing this moment. As to what that way is, that is why I need you, why I’ve fought to get you back on my side. You’re the expert on the Primitive. Tell me.”

            “I can’t,” groaned Harlan.

            “You can,” insisted Twissell.

            There was suddenly no trace of age or weariness in the old man’s voice. His eyes were ablaze with the light of combat and he wielded his cigarette like a lance. Even to Harlan’s regret-drugged senses the man seemed to be enjoying himself, actually enjoying himself, now that battle had been joined.

            “We can reconstruct the event,” said Twissell. “Here is the thrust control. You’re standing at it, waiting for the signal. It comes. You make contact and at the same time squeeze the power thrust in the downwhen direction. How far?”

            “I don’t know, I tell you. I don’t know.”

            “You don’t know, but your muscles do. Stand there and take the control in your hand. Get hold of yourself. Take them, boy. You’re waiting for the signal. You’re hating me. You’re hating the Council. You’re hating Eternity. You’re wearying your heart out for Noÿs. Put yourself back at that moment. Feel what you felt then. Now I’ll set the clock in motion again. ‘I’ll give you one minute, boy, to’ remember your emotions and force them back into your thalamus. Then, at the approach of zero, let your right hand jerk the control as it had done before. Then take your hand away! Don’t move it back again. Are you ready?”

            “I don’t think I can do it.”

            “You don’t think--Father Time, you have no choice. Is there another way you can get back your girl?”

            There wasn’t. Harlan forced himself back to the controls, and as he did so emotion flooded back. He did not have to call on it. Repeating the physical movements brought them back. The red hairline on the clock started moving.

            Detachedly he thought: The last minute of life?

            Minus thirty seconds.

            He thought: It will not hurt. It is not death.

            He tried to think only of Noÿs.

            Minus fifteen seconds.

            Noÿs!

            Harlan’s left hand moved a switch down toward contact.

            Minus twelve seconds.

            Contact!

            His right hand moved.

            Minus five seconds.

            Noÿs!

            His right hand mo--ZERO--ved spasmodically.

            He jumped away, panting.

            Twissell came forward, peering at the dial. “Twentieth Century,” he said. “Nineteen point three eight, to be exact.”

            Harlan choked out, “I don’t know. I tried to feel the same, but it was different. I knew what I was doing and that made it different.”

            Twissell said, “I know, I know. Maybe it’s all wrong. Call it a first approximation.” He paused a moment in mental calculation, took a pocket computer half out of its container and thrust it back without consulting it. “To Time with the decimal points. Say the probability is 0.99 that you sent him back to the second quarter of the 20th. Somewhere between 19.25 and 19.50. All right?”

            “I don’t know.”

            “Well, now, look. If I make a firm decision to concentrate on that part of the Primitive to the exclusion of all else and if I am wrong, the chances are that I will have lost my chance to keep the circle in time closed and Eternity will disappear. The decision itself will be the crucial point, the Minimum Necessary Change, the M.N.C., to bring about the Change. I now make the decision. I decide, definitely--”

            Harlan looked about cautiously, as though Reality had grown so fragile that a sudden head movement might shatter it.

            Harlan said, “I’m thoroughly conscious of Eternity.” (Twissell’s normality had infected him to the point where his voice sounded firm in his own ears.)

            “Then Eternity still exists,” said Twissell in a blunt, matter-of-fact manner, “and we have made the right decision. Now there’s nothing more to do here for the while. Let’s get to my office and we can let the subcommittee of the Council swarm over this place, if that will make them any happier. As far as they are concerned, the project has ended successfully. If it doesn’t, they’ll never know. Nor we.”

            Twissell studied his cigarette and said, “The question that now confronts us is this: What will Cooper do when he finds himself in the wrong Century?”

            “I don’t know.”

            “One thing is obvious. He’s a bright lad, intelligent, imaginative, wouldn’t you say?”

            “Well, he’s Mallansohn.”

            “Exactly. And he wondered if he would end up wrong. One of his last questions was: What if I don’t end up in the right spot? Do you remember?”

            “Well?” Harlan had no idea where this was leading.

            “So he is mentally prepared for being displaced in Time. He will do something. Try to reach us. Try to leave traces for us. Remember, for part of his life he was an Eternal. That’s an important thing.” Twissell blew a smoke ring, hooked it with a finger, and watched it curl about and break up. “He’s used to the notion of communication across Time, He is not likely to surrender to the thought of being marooned in Time. He’ll know that we’re looking for him.”

            Harlan said; “Without kettles and with no Eternity in the 20th, how would he go about communicating with us?”

            “With you, Technician, with you. Use the singular. You’re our expert on the Primitive. You taught Cooper about the Primitive. You’re the one he would expect to be capable of finding his traces.”

            “What traces, Computer?”

            Twissell’s shrewd old face stared up at Harlan, its lines crinkling. “It was intended to leave Cooper in the Primitive. He is without the protection of an enclosing shield of physiotime. His entire life is woven into the fabric of Time and will remain so until you and I reverse the alteration. Likewise woven into the fabric of Time is any artifact, sign, or message he may have left for us. Surely there must be particular sources you used in studying the 20th Century. Documents, archives, films, artifacts, reference works. I mean primary sources, dating from the Time itself.”

            “Yes.”

            “And he studied them with you?”

            “Yes.”

            “And is there any particular reference that was your favorite, one that he knew you were intimately acquainted with, so that you would recognize in it some reference to himself?”

            “I see what you’re driving at, of course,” said Harlan. He grew thoughtful.

            “Well?” asked Twissell with an edge of impatience.

            Harlan said, “My news magazines, almost surely. News magazines were a phenomenon of the early 20’s. The one of which I have nearly a complete set dates from early in the 20th and continues well into the 22nd.”

            “Good. Now is there any way, do you suppose, in which Cooper could make use of that news magazine to carry a message? Remember, he’d know you’d be reading the periodical, that you’d be acquainted with it, that you’d know your way about in it.”

            “I don’t know,” Harlan shook his head. “The magazine affected an artificial style. It was selective rather than inclusive and quite unpredictable. It would be difficult or even impossible to rely on its printing something you would plan to have it print. Cooper couldn’t very well create news and be sure of its appearance. Even if Cooper managed to get a position on its editorial staff, which is very unlikely, he couldn’t be certain that his exact wording would pass the various editors. I don’t see it, Computer.”

            Twissell said, “For Time’s sake, think! Concentrate on that news magazine. You’re in the 20th and you’re Cooper with his education and background. You taught the boy, Harlan. You molded his thinking. Now what would he do? How would he go about placing something in the magazine; something with the exact wording he wants?”

            Harlan’s eyes widened. “An advertisement!”

            “What?”

            “An advertisement. A paid notice which they would be compelled to print exactly as requested. Cooper and I discussed them occasionally.”

            “Ah, yes. They have that sort of thing in the 186th,” said Twissell.

            “Not like the 20th. The 20th is peak in that respect. The cultural milieu--”

            “Considering the advertisement now,” interposed Twissell hastily, “what kind would it be?”

            “I wish I knew.”

            Twissell stared at the lighted end of his cigarette as though seeking inspiration. “He can’t say anything directly: He can’t say: ‘Cooper of the 78th, stranded in the 20th and calling Eternity--’ “

            “How can you be sure?”

            “Impossible! To give the 20th information we know they did not have would be as damaging to the Mallansohn circle as would wrong action on our part. We’re still here, so in his whole lifetime in the current Reality of the Primitive he’s done no harm of that sort.”

            “Besides which,” said Harlan, retreating from the contemplation of the circular reasoning which seemed to bother Twissell so little, “the news magazine is not likely to agree to publish anything which seems mad to it or which it cannot understand. It would suspect fraud or some form of illegality and would not wish to be implicated. So Cooper couldn’t use Standard Intertemporal for his message.”

            “It would have to be something subtle,” said Twissell. “He would have to use indirection. He would have to place an advertisement that would seem perfectly normal to the men of the Primitive. Perfectly normal! And yet something that is obvious to us, once we knew what we were searching for. Very obvious. Obvious at a glance because it would have to be found among uncounted individual items. How big do you suppose it would be, Harlan? Are those advertisements expensive?”

            “Quite expensive, I believe.”

            “And Cooper would have to hoard his money. Besides which, to avoid the wrong kind of attention, it would have to be small, anyway. Guess, Harlan. How large?”

            Harlan spread his hands. “Half a column?”

            “Column?”

            “They were printed magazines, you know. On paper. With print arranged in columns.”

            “Oh yes. I can’t seem to separate literature and film somehow....Well, we have a first approximation of another sort now. We must look for a half-column advertisement which will, practically at a glance, give evidence that the man who placed it came from another Century (in the up when direction, of course) and yet which is so normal an advertisement that no man of that Century would see anything suspicious in it.”

            Harlan said, “What if I don’t find it?”

            “You will. Eternity exists, doesn’t it. As long as it does, we’re on the right track. Tell me, can you recall such an advertisement in your work with Cooper? Anything which struck you, even momentarily, as odd, queer, unusual, subtly wrong.”

            “No.”

            “I don’t want an answer so quickly. Take five minutes and think.”

            “No point. At the time I was going over the news magazines with Cooper; he hadn’t been in the 20th.”

            “Please, boy. Use your head. Sending Cooper to the 20th has introduced an alteration. There’s no Change; it isn’t an irreversible alteration. But there have been some changes with a small ‘c,’ or micro-changes, as it is usually referred to in Computation. At the instant Cooper was sent to the 20th, the advertisement appeared in the appropriate issue of the magazine. Your own Reality has micro-changed in the sense that you may have looked at the page with that advertisement on it rather than one without that advertisement as you did in the previous Reality. Do you understand?”

            Harlan was again bewildered, almost as much at the ease with which Twissell picked his way through the jungle of temporal logic, as at the “paradoxes” of Time. He shook his head, “I remember nothing of the sort.”

            “Well, then, where do you keep the files of that periodical?”

            “I had a special library built on Level Two, using the Cooper priority.”

            “Good enough,” said Twissell. “Let’s go there. Now!”

            Harlan watched Twissell stare curiously at the old, bound volumes in the library and then take one down. They were so old that the fragile paper had to be preserved by special methods and they creaked under Twissell’s insufficiently gentle handling.

            Harlan winced. In better times he would have ordered Twissell away from the books, Senior Computer though he was.

            The old man peered through the crinkling pages and silently mouthed the archaic words. “This is the English the linguists are always talking about, isn’t it?” he asked, tapping a page.

            “Yes. English,” muttered Harlan.

            Twissell put the volume back. “Heavy and clumsy.”

            Harlan shrugged. To be sure, most of the Centuries of Eternity were film eras. A respectable minority were molecular-recording eras. Still, print and paper were not unheard of.

            He said, “Books don’t require the investment in technology that films do.”

            Twissell rubbed his chin. “Quite. Shall we get started?”

            He took another volume down from the shelf, opening it at random and staring at the page with odd intentness.

            Harlan thought: Does the man think he’s going to hit the solution by a lucky stab?

            The thought might have been correct, for Twissell, meeting Harlan’s appraising eyes, reddened and put the book back.

            Harlan took the first volume of the 19.25th Centicentury and began turning the pages regularly. Only his right hand and his eyes moved. The rest of his body remained at rigid attention.

            At what seemed aeonic intervals to himself Harlan rose, grunting, for a new volume. On those occasions there would be the coffee break or the sandwich break or the other breaks.

            Harlan said heavily, “It’s useless your staying.” Twissell said, “Do I bother you?”

            “No.”

            “Then I’ll stay,” muttered Twissell. Throughout he wandered occasionally to the bookshelves, staring helplessly at the bindings. The sparks of his furious cigarettes burned his finger ends at times, but he disregarded them.

            A physioday ended.

            Sleep was poor and sparse. Midmorning, between two volumes, Twissell lingered over his last sip of coffee and said, “I wonder sometimes why I didn’t throw up my Computership after the matter of my--You know.”

            Harlan nodded.

            “I felt like it,” the old man went on. “I felt like it. For physiomonths, I hoped desperately that no Changes would come my way. I got morbid about it. I began to wonder if Changes were right. Funny, the tricks emotions will play on you.

            “You know Primitive history, Harlan. You know what it was like. Its Reality flowed blindly along the line of maximum probability. If that maximum probability involved a pandemic, or ten Centuries of slave economy, a breakdown of technology, or even a--a--let’s see, what’s really bad--even an atomic war if one had been possible then, why, by Time, it happened. There was nothing to stop it.

            “But where Eternity exists, that’s been stopped. Up when from the 28th, things like that don’t happen. Father Time, we’ve lifted our Reality to a level of well-being far beyond anything Primitive times could imagine; to a level which, but for the interference of Eternity, would have been very low probability indeed.”

            Harlan thought in shame: What’s he trying to do? Get me to work harder? I’m doing my best.

            Twissell said, “If we miss our chance now, Eternity disappears, probably through all of physiotime. And in one vast Change all Reality reverts to maximum probability with, I am positive, atomic warfare and the end of man.”

            Harlan said, “I’d better get on to the next volume.”

            At the next break Twissell said helplessly, “There’s so much to do. Isn’t there a faster way?”

            Harlan said, “Name it. To me it seems that I must look at every single page. And look at every part of it, too. How can I do it faster?”

            Methodically he turned the pages.

            “Eventually,” said Harlan, “the print starts blurring and that means it’s time for sleep.”

            A second physioday ended.

            At 10:22 A.M., Standard Physiotime, of the third physioday of the search Harlan stared at a page in quiet wonder and said, “This is it!”

            Twissell didn’t absorb the statement. He said, “What?”

            Harlan looked up, his face twisted with astonishment. “You know, I didn’t believe it. By Time, I never really believed it, even while you were working out all that rigmarole about news magazines and advertisements.”

            Twissell had absorbed it now. “You’ve found it!”

            He leaped at the volume Harlan was holding, clutching at it with shaking fingers.

            Harlan held it out of reach and slammed the volume shut. “Just a moment. You won’t find it, even if I showed you the page.”

            “What are you doing?” shrieked Twissell. “You’ve lost it.”

            “It’s not lost. I know where it is. But first--”

            “First what?”

            Harlan said, “There’s one point remaining, Computer Twissell. You say I can have Noÿs. Bring her to me, then. Let me see her.”

            Twissell stared at Harlan, his thin white hair in disarray. “Are you joking?”

            “No,” said, Harlan sharply, “I’m not joking. You assured me that you would make arrangements--Are you joking? Noÿs and I would be together. You promised that.”

            “Yes, I did. That part’s settled.”

            “Then produce her alive, well, and untouched.”

            “But I don’t understand you. I don’t have her. No one has. She’s still in the far up when, where Finge reported her to be. No one has touched her. Great Time, I told you she was safe.”

            Harlan stared at the old man and grew tense. He said chokingly, “You’re playing with words. All right, she’s in the far up when, but what good is that to me? Take down the barrier at the 100,000th--”

            “The what?”

            “The barrier. The kettle won’t pass it.”

            “You never said anything of this,” said Twissell wildly.

            “I haven’t?” said Harlan with sharp surprise. Hadn’t he? He had thought of it often enough. Had he never said a word about it? He couldn’t recall, at that. But then he hardened.

            He said, “All right. I tell you now. Take it down.”

            “But the thing is impossible. A barrier against the kettle?

            A temporal barrier?”

            “Are you telling me you didn’t put one up?”

            “I didn’t. By Time, I swear it.”.

            “Then--then--” Harlan felt himself grow pale. “Then the Council did it. They know of all this and they’ve taken action independently of you and--and by all of Time and Reality, they can whistle for their ad and for Cooper, for Mallansohn and all of Eternity. They’ll have none of it. None of it.”

            “Wait. Wait.” Twissell yanked despairingly at Harlan’s elbow. “Keep hold of yourself. Think, boy, think. The Council put up no barrier.”

            “It’s there.”

            “But they can’t have put up such a barrier. No one could have. It’s theoretically impossible.”

            “You don’t know it all. It’s there.”

            “I know more than anyone else on the Council and such a thing is impossible.”

            “But it’s there.”

            “But if it is--”

            And Harlan grew sufficiently aware of his surroundings to realize that there was a kind of abject fear in Twissell’s eyes; a fear that had not been there even when he first learned of Cooper’s misdirection and of the impending end of Eternity.

            16. The Hidden Centuries

            ANDREW HARLAN watched the men at work with abstracted eyes. They ignored him politely because he was a Technician. Ordinarily he would have ignored them somewhat less politely because they were Maintenance men. But now he watched them and, in his misery, he even caught himself envying them.

            They were service personnel from the Department of Intertemporal Transportation, in dun-gray uniforms with shoulder patches showing a red, double-headed arrow against a black background. They used intricate force-field equipment to test the kettle motors and the degrees of hyper-freedom along the kettleways. They had, Harlan imagined, little theoretical knowledge of temporal engineering, but it was obvious that they had a vast practical knowledge of the subject.

            Harlan had not learned much concerning Maintenance when he was a Cub. Or, to put it more accurately, he had not really wished to learn. Cubs who did not make the grade were put into Maintenance. The “unspecialized profession” (as the euphemism had it) was the hallmark of failure and the average Cub automatically avoided the subject.

            Yet now, as he watched the Maintenance men at work, they seemed to Harlan to be quietly, tensionlessly efficient, reasonably happy.

            Why not? They outnumbered the Specialists, the “true Eternals,” ten to one. They had a society of their own, residential levels devoted to them, pleasures of their own. Their labor was fixed at so many hours per physioday and there was no social pressure in their case to make them relate their spare-time activity to their profession. They had time, as Specialists did not, to devote to the literature and film dramatizations culled out of the various Realities.

            It was they, after all, who probably had the better-rounded personalities. It was the Specialist’s life which was harried and affected, artificial in comparison with the sweet and simple life in Maintenance.

            Maintenance was the foundation of Eternity. Strange that such an obvious fact had not struck him earlier. They supervised the importation of food and water from Time, the disposal of waste, the functioning of the power plants. They kept all the machinery of Eternity running smoothly. If every Specialist were to die of a stroke on the spot, Maintenance could keep Eternity going indefinitely. Yet were Maintenance to disappear, the Specialists would have to abandon Eternity in days or die miserably.

            Did Maintenance men resent the loss of their homewhens, or their womanless, childless lives? Was security from poverty, disease, and Reality Change sufficient compensation? Were their views ever consulted on any matter of importance? Harlan felt some of the fire of the social reformer within him.

            Senior Computer Twissell broke Harlan’s train of thought by bustling in at a half run, looking even more haunted than he had an hour before, when he had left, with Maintenance already at work.

            Harlan thought: How does he keep it up? He’s an old man.

            Twissell glanced about him with birdlike brightness as the men automatically straightened up to respectful attention.

            He said, “What about the kettleways?”

            One of the men responded, “Nothing wrong, sir. The ways are clear, the fields mesh.”

            “You’ve checked everything?”

            “Yes, sir. As far up when as the Department’s stations go.”

            Twissell said, “Then go.”

            There was no mistaking the brusque insistence of his dismissal. They bowed respectfully, turned, and hastened out briskly.

            Twissell and Harlan were alone in the kettleways.

            Twissell turned to him. “You’ll stay here. Please.”

            Harlan shook his head. “I must go.”

            Twissell said, “Surely you understand. If anything happens to me, you still know how to find Cooper. If anything happens to you, what can I or any Eternal or any combination of Eternals do alone?”

            Harlan shook his head again.

            Twissell put a cigarette between his lips. He said, “Sennor is suspicious. He’s called me several times in the last two physiodays. Why am I in seclusion, he wants to know. When he finds out I’ve ordered a complete overhaul of the kettleway machinery...I must go now, Harlan. I can’t delay.”

            “I don’t want delay. I’m ready.”

            “You insist on going?”

            “If there’s no barrier, there’ll be no danger. Even if there is, I’ve been there already and come back. What are you afraid of, Computer?”.

            “I don’t want to risk anything I don’t have to.”

            “Then use your logic, Computer. Make the decision that I’m to go with you. If Eternity still exists after that, then it means that the circle can still be closed. It means we’ll survive. If it’s a wrong decision, then Eternity will pass into nonexistence, but it will anyway if I don’t go, because without Noÿs, I’ll make no move to get Cooper. I swear it.”

            Twissell said, “I’ll bring her back to you.”

            “If it is so simple and safe, there will be no harm if I come along.”

            Twissell was in an obvious torture of hesitation. He said gruffly, “Well, then, come!”

            And Eternity survived.

            Twissell’s haunted look did not disappear once they were within the kettle. He stared at the skimming figures of the temporometer. Even the scaler gauge, which measured in units of Kilocenturies, and which the men had adjusted for this particular purpose, was clicking at minute intervals.

            He said, “You should not have come.”

            Harlan shrugged. “Why not?”

            “It disturbs me. No sensible reason. Call it a long-standing superstition of mine. It makes me restless.” He clasped his hands together, holding them tightly.

            Harlan said, “I don’t understand you.”

            Twissell seemed eager to talk, as though to exorcise some mental demon. He said, “Maybe you’ll appreciate this, at that. You’re the expert on the Primitive. How long did man exist in the Primitive?”

            Harlan said, “Ten thousand Centuries. Fifteen thousand, maybe.”

            “Yes. Beginning as a kind of primitive apelike creature and ending as Homo sapiens. Right?”

            “It’s common knowledge. Yes.”

            “Then it must be common knowledge that evolution proceeds at a fairly rapid pace. Fifteen thousand Centuries from ape to Homo sapiens.”

            “Well?”

            “Well, I’m from a Century in the 30,000’s--”

            (Harlan could not help starting. He had never known Twissell’s homewhen or known of anyone who did.)

            “I’m from a Century in the 30,000’s,” Twissell said again, “and you’re from the 95th. The time between our homewhens is twice the total length of time of man’s existence in the Primitive, yet what change is there between us? I was born with four fewer teeth than you, and without an appendix. The physiological differences about end with that. Our metabolism is almost the same. The major difference is that your body can synthesize the steroid nucleus and my body can’t, so that I require cholesterol in my diet and you don’t. I was able to breed with a woman of the 575th. That’s how undifferentiated with time the species is.”

            Harlan was unimpressed. He had never questioned the basic identity of man throughout the Centuries. It was one of those things you lived with and took for granted. He said, “There have been cases of species living unchanged through millions of Centuries.”

            “Not many, though. And it remains a fact that the cessation of human evolution seems to coincide with the development of Eternity. Just coincidence? It’s not a question which is considered, except by a few here and there like Sennor, and I’ve never been a Sennor. I didn’t believe speculation was proper. If something couldn’t be checked by a Computaplex, it had no business taking up the time of a Computer. And yet, in my younger days, I sometimes thought--”

            “Of what?” Harlan thought: Well, it’s something to listen to, anyway.

            “I sometimes thought about Eternity as it was when it was first established. It stretched over just a few Centuries in the 30’s and 40’s, and its function was mostly trade. It interested itself in the reforestation of denuded areas, shipping topsoil back and forth, fresh water, fine chemicals. Those were simple days.

            “But then we discovered Reality Changes. Senior Computer Henry Wadsman, in the dramatic manner with which we are all acquainted, prevented a war by removing the safety brake of a Congressman’s ground vehicle. After that, more and more, Eternity shifted its center of gravity from trade to Reality Change. Why?”

            Harlan said, “The obvious reason. Betterment of humanity.”

            “Yes. Yes. In normal times, I think so too. But I’m talking of my nightmare. What if there were another reason, an unexpressed one, an unconscious one. A man who can travel into the indefinite future may meet men as far advanced over himself as he himself is over an ape. Why not?”

            “Maybe. But men are men--”

            “--even in the 70,000th. Yes, I know. And have our Reality Changes had something to do with it? We bred out the unusual. Even Sennor’s homewhen with its hairless creatures is under continual question and that’s harmless enough. Perhaps in all honesty, in all sincerity, we’ve prevented human evolution because we don’t want to meet the supermen.”

            Still no spark was struck. Harlan said, “Then it’s done. What does it matter?”

            “But what if the superman exists just the same, further up when than we can reach? We control only to the 70,000th. Beyond that are the Hidden Centuries! Why are they hidden? Because evolved man does not want to deal with us and bars us from his time? Why do we allow them to remain hidden? Because we don’t want to deal with them and, having failed to enter in our first attempt, we refuse even to make additional attempts? I don’t say it’s our conscious reason, but conscious or unconscious, it’s a reason.”

            “Grant everything,” said Harlan sullenly. “They’re out of our reach and we’re out of theirs. Live and let live.”

            Twissell seemed struck by the phrase. “Live and let live. But we don’t. We make Changes. The Changes extend only through a few Centuries before temporal inertia causes its effects to die out. You remember Sennor brought that up as one of the unanswered problems of Time at our breakfast. What he might have said was that it’s all a matter of statistics. Some Changes affect more Centuries than other. Theoretically, any number of Centuries can be affected by the proper Change; a hundred Centuries, a thousand, a hundred thousand. Evolved man of the Hidden Centuries may know that. Suppose he is disturbed by the possibility that someday a Change may reach him clear to the 200,000th.”

            “It’s useless to worry about such things,” said Harlan with the air of a man who had much greater worries.

            “But suppose,” went on Twissell in a whisper, “they were calm enough as long as we left the Sections of the Hidden Centuries empty. It meant we weren’t aggressing. Suppose this truce, or whatever you wish to call it, were broken, and someone appeared to have established permanent residence up when from the 70,000th. Suppose they thought it might mean the first of a serious invasion? They can bar us from their Time, so their science is that far advanced beyond ours. Suppose they may further do what seems impossible to us and throw a barrier across the kettleways, cutting us off--”

            And now Harlan was on his feet, in full horror, “They have Noÿs?”

            “I don’t know. It’s speculation. Maybe there is no barrier. Maybe there was something wrong with your ket--”

            “There was a barrier!” yelled Harlan. “What other explanation is there? Why didn’t you tell me this before.”

            “I don’t believe it,” groaned Twissell. “I still don’t. I shouldn’t have said a word of this foolish dreaming. My own fears--the question of Cooper--everything--But wait, just a few minutes.”

            He pointed at the temporometer. The scaler indicated them to be between the 95,000th and 96,000th Centuries.

            Twissell’s hand on the controls slowed the kettle. The 99,000th was passed. The scaler’s motions stopped. The individual Centuries could be read.

            99, 726--99,727--99,728

            “What will we do?” muttered Harlan.

            Twissell shook his head in a gesture that spoke eloquently of patience and hope, but perhaps also of helplessness.

            99,851--99,852--99,853--

            Harlan steeled himself for the shock of the barrier and thought desperately: Would preserving Eternity be the only means of finding time to fight back at the creatures of the Hidden Centuries? How else recover Noÿs? Dash back, back to the 575th and work like fury to--

            99,938--99,939--99,940--

            Harlan held his breath. Twissell slowed the kettle further, let it creep. It responded perfectly to the controls.

            99,984--99,985--99,986--

            “Now, now, now,” said Harlan in a whisper, unaware that he had made any sound at all.

            99,998--99,999--100,000--100,101--100, 102--

            The numbers mounted and the two men watched them continue to mount in paralytic silence.

            Then Twissell cried, “There is no barrier.”

            And Harlan answered, “There was! There was!” Then, in agony, “Maybe they’ve got her, and need a barrier no longer.”

            111,394th!

            Harlan leaped from the kettle, and raised his voice. “Noÿs! Noÿs!”

            The echoes bounced off the walls of the empty Section in hollow syncopation.

            Twissell, climbing out more sedately, called after the younger man, “Wait, Harlan--”

            That was useless. Harlan, at a run, was hurtling along the corridors toward that portion of the Section they had made a kind of home.

            He thought vaguely of the possibility of meeting one of Twissell’s “evolved men” and momentarily his skin prickled, but then that was drowned in his urgent need to find Noÿs.

            “Noÿs!”

            And all at once, so quickly that she was in his arms before he was sure he had seen her at all, she was there with him, and her arms were around him and clutching him and her cheek was against his shoulder and her dark hair was soft against his chin.

            “Andrew?” she said, her voice muffled by the pressure of his body. “Where were you? It’s been days and I was getting frightened.”

            Harlan held her out at arm’s length, staring at her with a kind of hungry solemnity. “Are you all right?”

            “I’m all right. I thought something might have happened to you. I thought--” She broke off, terror springing into her eyes and gasped, “Andrew!”

            Harlan whirled.

            It was only Twissell, panting.

            Noÿs must have gained confidence from Harlan’s expression. She said more quietly, “Do you know him, Andrew? Is it all right?”

            Harlan said, “It’s all right. This is my superior, Senior Computer Laban Twissell. He knows of you.”

            “A Senior Computer?” Noÿs shrank away.

            Twissell advanced slowly. “I will help you, my child. I will help you both. The Technician has my promise, if he would only believe it.”

            “My apologies, Computer,” said Harlan stiffly, and not yet entirely repentant.

            “Forgiven,” said Twissell. He held out his hand, took the girl’s reluctant one. “Tell me, girl, has it been well with you here?”

            “I’ve been worried.”

            “There’s been no one here, since Harlan last left you.”

            “N--no, sir.”

            “No one at all? Nothing?”

            She shook her head. Her dark eyes sought Harlan’s. “Why do you ask?”

            “Nothing, girl. A foolish nightmare. Come, we will take you back to the 575th.”

            On the kettle back Andrew Harlan sank, by degrees, into a troubled and deepening silence. He did not look up when the l00,000th was passed in the downwhen direction and Twissell had snorted an obvious sigh of relief as though he had half expected to be trapped on the up when side.

            He scarcely moved when Noÿs” hand stole into his, and the manner in which he returned the pressure of her fingers was almost mechanical.

            Noÿs slept in another room and now Twissell’s restlessness reached a peak of devouring intensity.

            “The advertisement, boy! You have your woman. My part of the agreement is done.”

            Silently, still abstracted, Harlan turned the pages of the volume on the desk. He found his page.

            “It’s simple enough,” he said, “but it’s in. English. I’ll read it to you and then translate it.”

            It was a small advertisement in the upper left-hand corner of a page numbered 30. Against an irregular line drawing as background were the unadorned words, in block letters:

            ALL THE

            TALK

            OF THE

            MARKET

            Underneath, in smaller letters, it said; “Investments News-Letter, P. O. Box 14, Denver, Colorado.”

            Twissell listened painstakingly to Harlan’s translation and was obviously disappointed. He said, “What is the market? What do they mean by that?”

            “The stock market,” said Harlan impatiently. “A system by which private capital was invested in business. But that’s not the point at all. Don’t you see the line drawing against which the advertisement is set?”

            “Yes. The mushroom cloud of an A-bomb blast. An attention getter. What about it?”

            Harlan exploded. “Great Time, Computer, what’s wrong with you? Look at the date of the magazine issue.”

            He pointed to the top heading, just to the left of the page number. It read March 28, 1932.

            Harlan said, “That scarcely needs translation. The numbers are about those of Standard Intertemporal and you see it’s the 19.32nd Century. Don’t you know that at that time no human being who had ever lived had seen the mushroom cloud? No one could possibly reproduce it so accurately, except--”

            “Now, wait. It’s just a line pattern,” said Twissell, trying to retain his equilibrium. “It might resemble the mushroom cloud only coincidentally.”

            “Might it? Will you look at the wording again?” Harlan’s fingers punched out the short lines: “All the--Talk--Of the--Market. The initials spell out ATOM, which is English for atom. Is that coincidence, too? Not a chance.

            “Don’t you see, Computer, how this advertisement fits the conditions you yourself set up? It caught my eye instantly. Cooper knew it would out of sheer anachronism. At the same time, it has no meaning other than its face value, no meaning at all, for any man of the 19.32nd.

            “So it must be Cooper. That’s his message. We have the date to the nearest week of a Centicentury. We have his mailing address. It is only necessary to go after him and I’m the only one with enough knowledge of the Primitive to manage that.”

            “And you’ll go?” Twissell’s face was ablaze with relief and happiness.

            “I’ll go--on one condition.”

            Twissell frowned in a sudden reversal of emotion. “Again conditions?”

            “The same condition. I’m not adding new ones. Noÿs must be safe. She must come with me. I will not leave her behind.”

            “You still don’t trust me? In what way have I failed you? What can there be that still disturbs you?”

            “One thing, Computer,” said Harlan solemnly. “One thing still. There was a barrier across the l00,000th. Why? That is what still disturbs me.”

            17. The Closing Circle

            IT DID NOT stop disturbing him. It was a matter that grew in mind as the days of preparation sped by. It interposed itself between him and Twissell; then between him and Noÿs. When the day of departure came, he was only distantly aware of the fact.

            It was all he could do to rouse a shadow of interest when Twissell returned from a session with the Council subcommittee. He said, “How did it go?”

            Twissell said wearily, “It wasn’t exactly the most pleasant conversation I’ve ever had.”

            Harlan was almost willing to let it go at that, but he broke his moment’s silence with a muttered “I suppose you said nothing about--”

            “No, no,” was the testy response. “I said nothing about the girl or about your part in the misdirection of Cooper. It was an unfortunate error, a mechanical failure, I took full responsibility.”

            Harlan’s conscience, burdened as it was, could find room for a twinge. He said, “That won’t affect you well.”

            “What can they do? They must wait for the correction to be made before they can touch me. If we fail, we’re all beyond help or harm. If we succeed, success itself will probably protect me. And if it doesn’t--” The old man shrugged. “I plan to retire from active participation in Eternity’s affairs thereafter anyway.” But he fumbled his cigarette and disposed of it before it was half burned away.

            He sighed. “I would rather not have brought them into this at all, but there would have been no way, otherwise, of using the special kettle for further trips past the downwhen terminus.”

            Harlan turned way. His thoughts moved around and about the same channels that had been occupied to the increasing exclusion of all else for days. He heard Twissell’s further remark dimly, but it was only at its repetition that he said with a start, “Pardon me?”

            “I say, is your woman ready, boy? Does she understand what she’s to do?”

            “She’s ready. I’ve told her everything.”

            “How did she take it?”

            “What?...Oh, yes, uh, as I expected her to. She’s not afraid.”

            “It’s less than three physiohours now.”

            “I know.”

            That was all for the moment, and Harlan was left alone with his thoughts and a sickening realization of what he must do.

            With the kettle loading done and the controls adjusted Harlan and Noÿs appeared in a final change of costume, approximating that of an unurbanized area of the early 20th.

            Noÿs had modified Harlan’s suggestion for her wardrobe, according to some instinctive feeling she claimed women had when it came to matters of clothing and aesthetics. She chose thoughtfully from pictures in the advertisements of the appropriated volumes of the news magazine and had minutely scrutinized items imported from a dozen different Centuries.

            Occasionally she would say to Harlan, “What do you think?”

            He would shrug. “If it’s instinctive knowledge, I’ll leave it to you.”

            “That’s a bad sign, Andrew,” she said, with a lightness that did not quite ring true. “You’re too pliable. What’s the matter, anyway? You’re just not yourself. You haven’t been for days.”

            “I’m all right,” Harlan said in a monotone.

            Twissell’s first sight of them in the role of natives of the 20th elicited a feeble attempt at jocularity. “Father Time,” he said, “what ugly costumes in the Primitive, and yet how it fails to hide your beauty, my--my dear.”

            Noÿs smiled warmly at him, and Harlan, standing there impassively silent; was forced to admit that Twissell’s rust-choked vein of gallantry had something of truth in it. Noÿs’s clothing encompassed her without accentuating her as clothing should. Her make-up was confined to unimaginative dabs of color on lips and cheeks and an ugly rearrangement of the eyebrow line. Her lovely hair (this had been the worst of it) had been cut ruthlessly. Yet she was beautiful.

            Harlan himself was already growing accustomed to his own uncomfortable belt, the tightness of fit under armpits and in the crotch and the mousy lack of color about his rough-textured clothing. Wearing strange costumes to suit a Century was an old story to him.

            Twissell was saying, “Now what I really wanted to do was to install hand controls inside the kettle, as we discussed, but there isn’t any way, apparently. The engineers simply must have a source of power large enough to handle temporal displacement and that isn’t available outside Eternity. Temporal tension while occupying the Primitive is all that can be managed. However, we have a return lever.”

            He led them into the kettle, picking his way among the piled supplies, and pointed out the obtruding finger of metal that now marred the smooth inner wall of the kettle.

            “It amounts to the installation of a simple switch,” he said. “Instead of returning automatically to Eternity, the kettle will remain in the Primitive indefinitely. Once the lever is plunged home, however, you will return. There will then be the matter of the second and, I hope, final trip--”

            “A second trip?” asked Noÿs at once.

            Harlan said, “I haven’t explained that. Look, this first trip is intended merely to fix the time of Cooper’s arrival precisely. We don’t know how long a Time-lapse exists between his arrival and the placing of the advertisement. We’ll reach him by the post-office box, and learn; if possible, the exact minute of his arrival, or as close as we can, anyway. We can then return to that moment plus fifteen minutes to allow for the kettle to have left Cooper--”

            Twissell interposed, “Couldn’t have the kettle in the same place at the same time in two different physiotimes, you know,” and tried to smile.

            Noÿs seemed to absorb it. “I see,” she said, not too definitely.

            Twissell said to Noÿs, “Picking up Cooper at the time of his arrival will reverse all micro-changes. The A-bomb advertisement will disappear again and Cooper will know only that the kettle, having disappeared as we told him it would, had unexpectedly appeared again. He will not know that he was in the wrong Century and he will not be told. We will tell him that there was some vital instruction we had forgotten to give him (we’ll have to manufacture some) and we can only hope that he will regard the matter as so unimportant that he won’t mention being sent back twice when he writes his memoir.”

            Noÿs lifted her plucked eyebrows. “It’s very complicated.”

            “Yes. Unfortunately.” He rubbed his hands together and looked at the others as though nursing an inner doubt. Then he straightened, produced a fresh cigarette, and even managed a certain jauntiness as he said, “And now, boy, good luck.” Twissell touched hands briefly with Harlan, nodded to Noÿs, and stepped out of the kettle.

            “Are we leaving now?” asked Noÿs of Harlan when they were alone.

            “In a few minutes,” said Harlan.

            He glanced sideways at Noÿs. She was looking up at him, smiling, unfrightened. Momentarily his own spirits responded to that. But that was emotion, not reason, he counseled himself, instinct, not thought. He looked away.

            The trip was nothing, or almost nothing; no different from an ordinary kettle ride. Midway there was a kind of internal jar that might have been the downwhen terminus and might have been purely psychosomatic. It was barely noticeable.

            And then they were in the --Primitive and they stepped into a craggy, lonely world brightened by the splendor of an afternoon sun. There was a soft wind with a chilly edge to it and, most of all, silence.

            The bare rocks were tumbled and mighty, colored into dull rainbows by compounds of iron, copper, and chromium. The grandeur of the manless and all but lifeless surroundings dwarfed and shriveled Harlan. Eternity, which did not belong to the world of matter, had no sun and none but imported air. His memories of his own homewhen were dim. His Observations in the various Centuries had dealt with men and their cities. He had never experienced this.

            Noÿs touched his elbow. “Andrew! I’m cold.”

            He turned to her with a start.

            She said, “Hadn’t we better set up the Radiant?”

            He said, “Yes. In Cooper’s cavern.”

            “Do you know where it is?”

            “It’s right here,” he said shortly.

            He had no doubt of that. The memoir had located it and first Cooper, now he, had been pin-pointed back to it.

            He had not doubted precision pin-pointing in Time-travel since his Cubhood days. He remembered himself then, facing Educator Yarrow seriously, saying, “But Earth moves about the Sun, and the Sun moves about the Galactic Center and the Galaxy moves too. If you start from some point on Earth, and move downwhen a hundred years, you’ll be in empty space, because it will take a hundred years for Earth to reach that point.” (Those were the days when he still referred to a Century as a “hundred years.”)

            And Educator Yarrow had snapped back, “You don’t separate Time from space. Moving through Time, you share Earth’s motions. Or do you believe that a bird flying through the air whiffs out into space because the Earth is hurrying around the Sun at eighteen miles a second and vanishes from under the creature?”

            Arguing from analogy is risky, but Harlan obtained more rigorous proof in later days and, now, after a scarcely precedented trip into the Primitive, he could turn confidently and feel no surprise at finding the opening precisely where he had been told it would be.

            He moved the camouflage of loose rubble and rock to one side and entered.

            He probed the darkness within, using the white beam of his flash almost like a scalpel. He scoured the walls, ceiling, floor, every inch.

            Noÿs, remaining close behind him, whispered, “What are you looking for?”

            He said, “Something. Anything.”

            He found his something, anything, at the very rear of the cave in the shape of a flattish stone covering greenish sheets like a paperweight.

            Harlan threw the stone aside and flipped the sheets past one thumb.

            “What are they?” asked Noÿs.

            “Bank notes. Medium of exchange. Money.”

            “Did you know they were there?”

            “I knew nothing. I just hoped.”

            It was only a matter of using Twissell’s reverse logic, of calculating cause from effect. Eternity existed, so Cooper must be making correct decisions too. In assuming the advertisement would pull Harlan into the correct Time, the cave was an obvious additional means of communication.

            Yet this was almost better than he had dared hope. More than once during the preparations for his trip into the Primitive, Harlan had thought that making his way into a town with nothing but bullion in his possession would result in suspicion and delay.

            Cooper had managed, to be sure, but Cooper had had time. Harlan hefted the sheaf of bills. And he must have used time to accumulate this much. He had done well, the youngster, marvelously well.

            And the circle was closing!

            The supplies had been moved into the cave, in the increasingly ruddy glow of the westering sun. The kettle had been covered by a diffuse reflecting film which would hide it from any but the closest of prying eyes, and Harlan had a blaster to take care of those, if need be. The Radiant was set up in the cave and the flash was wedged into a crevice, so that they had heat and light.

            Outside it was a chill March night.

            Noÿs stared thoughtfully into the smooth paraboloid interior of the Radiant as it slowly rotated. She said, “Andrew, what are your plans?”

            “Tomorrow morning,” he said, “I’ll leave for the nearest town. I know where it is--or should be.” (He changed it back to “is” in his mind. There would be no trouble. Twissell’s logic again.)

            “I’ll come with you, won’t I?”

            He shook his head, “You can’t speak the language, for one thing, and the trip will be difficult enough for one to negotiate.”

            Noÿs looked strangely archaic in her short hair and the sudden anger in her eyes made Harlan look away uneasily.

            She said, “I’m no fool, Andrew. You scarcely speak to me. You don’t look at me. What is it? Is your homewhen morality taking hold? Do you feel you have betrayed Eternity and are you blaming me for that? Do you feel I have corrupted you? What is it?”

            He said, “You don’t know what I feel.”

            She said, “Then describe it. You might as well. You’ll never have a chance as good as this one. Do you feel love? For me? You couldn’t or you wouldn’t be using me as a scapegoat. Why did you bring me here? Tell me. Why not have left me in Eternity since you have no use for me here and since it seems you can hardly bear the sight of me?”

            Harlan muttered, “There’s danger.”

            “Oh, come now.”

            “It’s more than danger. It’s a nightmare. Computer Twissell’s nightmare,” said Harlan. “It was during our last panicky flash up when into the Hidden Centuries that he told me of thoughts he had had concerning those Centuries. He speculated on the possibility of evolved varieties of man, new species, supermen perhaps, hiding in the far up when, cutting themselves off from our interference, plotting to end our tamperings with Reality. He thought it was they who built the barrier across the 100,000th. Then we found you, and Computer Twissell abandoned his nightmare. He decided there had never been a barrier. He returned to the more immediate problem of salvaging Eternity.

            “But I, you see, had been infected by his nightmare. I had experienced the barrier, so I knew it existed. No Eternal had built it, for Twissell said such a thing was theoretically impossible. Maybe Eternity’s theories didn’t go far enough. The barrier was there. Someone had built it. Or something.

            “Of course,” he went on thoughtfully, “Twissell was wrong in some ways. He felt that man must evolve, but that’s not so. Paleontology is not one of the sciences that interest Eternals, but it interested the late Primitives, so I picked up a bit of it myself. I know this much: species evolve only to meet the pressures of new environments. In a stable environment, a species may remain unchanged for millions of Centuries. Primitive man evolved rapidly because his environment was a harsh and changing one. Once, however, mankind learned to create his own environment, he created a pleasant and stable one, so he just naturally stopped evolving.”

            “I don’t know what you’re talking about,” said Noÿs, sounding not the least mollified, “and you’re not saying anything about us, which is what I want to talk about.”

            Harlan managed to remain outwardly unmoved. He said, “Now why the barrier at the l00,000th? What purpose did it serve? You weren’t harmed. What other meaning could it have? I asked myself: What happened because of its presence that would not have happened had it been absent?”

            He paused, looking at his clumsy and heavy boots of natural leather. It occurred to him that he could add to his comfort by removing them for the night, but not now, not now...

            He said, “There was only one answer to that question. The existence of that barrier sent me raving back downwhen to get a neuronic whip, to assault Finge. It fired me to the thought of risking Eternity to get you back and smashing Eternity when I thought I had failed. Do you see?”

            Noÿs stared at him with a mixture of horror and disbelief. “Do you mean the people in the up when wanted you to do all that? They planned it?”

            “Yes. Don’t look at me like that. Yes! And don’t you see how it makes everything different? As long as I acted on my own, for reasons of my own, I’ll take all the consequences, material and spiritual. But to be fooled into it, to be tricked into it, by people handling and manipulating my emotions as though I were a Computaplex on which it was only necessary to insert the properly perforated foils--”

            Harlan realized suddenly that he was shouting and stopped abruptly. He let a few moments pass, then said, “That is impossible to take. I’ve got to undo what I was marionetted into doing. And when I undo it, I will be able to rest again.”

            And he would--perhaps. He could feel the coming of an impersonal triumph, dissociated from the personal tragedy which lay behind and ahead. The circle was closing!

            Noÿs’s hand reached out uncertainly as though to take his own rigid, unyielding one.

            Harlan drew away, avoided her sympathy. He said, “It had an been arranged. My meeting with you. Everything. My emotional make-up had been analyzed. Obviously. Action and response. Push this button and the man will do that. Push that button and he will do this.”

            Harlan was speaking with difficulty, out of the depths of shame. He shook his head, trying to shake the horror of it away as a dog would water, then went on. “One thing I didn’t understand at first. How did I come to guess that Cooper was to be sent back into the primitive? It was a most unlikely thing to guess. I had no basis. Twissell didn’t understand it. More than once he wondered how I could have done it with so little understanding of mathematics.

            “Yet I had. The first time was that--that night. You were asleep, but I wasn’t. I had the feeling then that there was something I must remember; some remark, some thought, something that I had caught sight of in the excitement and exhilaration of the evening. When I thought long, the whole significance of Cooper sprang into my mind, and along with it the thought entered my mind that I was in a position to destroy Eternity. Later I checked through histories of mathematics, but it was unnecessary really. I already knew. I was certain of it. How? How?”

            Noÿs stared at him intently. She didn’t try to touch him now. “Do you mean the men of the Hidden Centuries arranged that, too? They put it all in your mind, then maneuvered you properly?”

            “Yes. Yes. Nor are they done. There is still work for them to do. The circle may be closing, but it is not yet closed.”

            “How can they do anything now? They’re not here with us.”

            “No?” He said the word in so hollow a voice that Noÿs paled.

            “Invisible superthings?” she whispered.

            “Not superthings. Not invisible. I told you man would not evolve while he controlled his own environment. The people of the Hidden Centuries are Homo sapiens. Ordinary people.”

            “Then they’re certainly not here.”

            Harlan said sadly, “You’re here, Noÿs.”

            “Yes. And you. And no one else.”

            “You and I,” agreed Harlan. “No one else. A woman of the Hidden Centuries and I...Don’t act any more, Noÿs. Please.”

            She stared at him with horror. “What are you saying, Andrew?”

            “What I must say. What were you saying that evening, when you gave me the peppermint drink? You were talking to me. Your soft voice-soft words...I heard nothing, not consciously, but I remember your delicate voice whispering. About what? The downwhen journey of Cooper; the Samson-smash of Eternity. Am I right?”

            Noÿs said, “I don’t even know what Samson-smash means.”

            “You can guess very accurately, Noÿs. Tell me, when did you enter the 482nd? Whom did you replace? Or did you just--squeeze in. I had your Life-Plot worked out by an expert in the 2456th. In the new Reality, you had no existence at all. No analogue. Strange for such a small Change, but not impossible. And then the Life-Plotter said one thing which I heard with my ears but not with my mind. Strange that I should remember it. Perhaps even then, something clanged in my mind, but I was too full of you to listen. He said: ‘with the combination of factors you handed me, I don’t quite see how she fit in the old Reality.’

            “He was right. You didn’t fit in. You were an invader from the far up when, manipulating me and Finge, too, to suit yourself.”

            Noÿs said urgently, “Andrew--”

            “It all fit in, if I had the eyes to look. A book-film in your house entitled Social and Economic History. It surprised me when first I saw it. You needed it, didn’t you, to teach you how best to be a woman of the Century. Another item. Our first trip into the Hidden Centuries, remember? You stopped the kettle at the 111,394th. You stopped it with finesse, without fumbling. Where did you learn to control a kettle? If you were what you seemed to be, that would have been your first trip in a kettle. Why the 111,394th, anyway? Was it your homewhen?”

            She said softly, “Why did you bring me to the Primitive, Andrew?”

            He shouted suddenly, “To protect Eternity. I could not tell what damage you might do there. Here, you are helpless, because I know you. Admit that all I say is true! Admit it!”

            He rose in a paroxysm of wrath, arm upraised. She did not flinch. She was utterly calm. She might have been modeled out of warm, beautiful wax. Harlan did not complete his motion.

            He said, “Admit it!”

            She said, “Are you so uncertain, after all your deductions? What will it matter to you whether I admit it or not.”

            Harlan felt the wildness mount. “Admit it, anyway, so that I need feel no pain at all. None at all.”

            “Pain?”

            “Because I have a blaster, Noÿs, and it is my intention to kill you.”

            18. The Beginning of Infinity

            THERE WAS a crawling uncertainty inside Harlan, an irresolution that was consuming him: He had the blaster in his hand. It was aimed at Noÿs.

            But why did she say nothing? Why did she persist in this impassive attitude?

            How could he kill her?

            How could he not kill her?

            He said hoarsely, “Well?”

            She moved, but it was only to clasp her bands loosely in her lap, to look more relaxed, more aloof. When she spoke her voice seemed scarcely that of a human being. Facing the muzzle of a blaster, it yet gained assurance and took on an almost mystic quality of impersonal strength.

            She said, “You cannot wish to kill me only in order to protect Eternity. If that were your desire, you could stun me, tie me firmly, pin me within this cave and then take to your travels in the dawn; Or you might have asked Computer Twissell to keep me in solitary confinement during your absence in the Primitive. Or you might take me with you at dawn, lose me in the wastes. If it is only killing that will satisfy you, it is only because you think that I have betrayed you, that I have tricked you into love first in order that I might trick you into treason later. This is murder out of wounded pride and not at all the just retribution you tell yourself it is.”

            Harlan squirmed. “Are you from the Hidden Centuries? Tell me.”

            Noÿs said, “I am. Will you now blast?”

            Harlan’s finger trembled on the blaster’s contact point. Yet he hesitated. Something irrational within him could still plead her case and point up the remnants of his own futile love and longing. Was she desperate at his rejection of her? Was she deliberately courting death by lying? Was she indulging in foolish heroics born of despair at his doubts of her?

            No!

            The book-films of the sickly-sweet literary tradition of the 289th might have it so, but not a girl like Noÿs. She was not one to meet her death at the hands of a false lover with the joyful masochism of a broken, bleeding lily.

            Then was she scornfully denying his ability to kill her for any reason whatever? Was she confidently relying on the attraction she knew she had for him even now, certain that it would immobilize him, freeze him in weakness and shame.

            That hit too closely. His finger clamped a bit harder on the contact.

            Noÿs spoke again. “You’re waiting. Does that mean you expect me to enter a brief for the defense?”

            “What defense?” Harlan tried to make that scornful, yet he welcomed the diversion. It could postpone the moment when he must look down upon her blasted body, upon whatever remnants of bloody flesh might remain, and Know that what had been done to his beautiful Noÿs had been done by his own hand.

            He found excuses for his delay. He thought feverishly: Let her talk. Let her tell what she can about the Hidden Centuries. So much better protection for Eternity.

            It put a front of firm policy on his action and for the moment he could look at her with as calm a face, almost, as she looked at him.

            Noÿs might have read his mind. She said, “Do you want to know about the Hidden Centuries? If that will be a defense, it is easily done. Would you like to know, for instance, why Earth is empty of mankind after the 150,000th? Would you be interested?”

            Harlan wasn’t going to plead for knowledge, nor was he going to buy knowledge. He had the blaster. He was very intent on no show of weakness.

            He said, “Talk!” and flushed at the little smile which was her first response to his exclamation.

            She said, “At a moment in physiotime before Eternity had reached very far up when, before it had reached even the l0,000th, we of our Century--and you’re right, it was the lll,394th--learned of Eternity’s existence. We, too, had Time-travel, you see, but it was based on a completely different set of postulates than yours, and we preferred to view Time, rather than shifting mass. Furthermore, we dealt with our past only, our downwhen.

            “We discovered Eternity indirectly. First, we developed the calculus of Realities and tested our own Reality through it. We were amazed to find we lived in a Reality of rather low probability. It was a serious question. Why such an improbable Reality?...You seem abstracted, Andrew! Are you interested at all?”

            Harlan heard her say his name with all the intimate tenderness she had used in weeks past. It should grate on him now, anger him with its cynical faithlessness. And yet it didn’t.

            He said desperately, “Go on and get it over with, woman.”

            He tried to balance the warmth of her “Andrew” with the chill anger of his “woman” and yet she only smiled again, pallidly.

            She said, “We searched back through time and came across the growing Eternity. It seemed obvious to us almost at once that there had been at one point in physiotime (a conception we have also, but under another name) another Reality. The other Reality, the one of maximum probability we call the Basic State. The Basic State had encompassed us once, or had encompassed our analogues, at least. At the time we could not say what the nature of the Basic State was. We could not possibly know.

            “We did know, however, that some Change initiated by Eternity in the far downwhen had managed, through the workings of statistical chance, to alter the Basic State all the way up to our Century and beyond. We set about determining the nature of the Basic State, intending to undo the evil, if evil it was. First we set up the quarantined area you call the Hidden Centuries, isolating the Eternals on the downwhen side of the 70,000th. This armor of isolation would protect us from all but a vanishingly small percentage of the Changes being made. It wasn’t absolute security but it gave us time.

            “We next did something our culture and ethics did not ordinarily allow us to do. We investigated our own future, our up when. We learned the destiny of man in the Reality that actually existed in order that we might compare it eventually with Basic State. Somewhere past the 125,000th, mankind solved the secret of the interstellar drive. They learned how to manage the Jump through hyperspace. Finally, mankind could reach the stars.”

            Harlan was listening in growing absorption to her measured words. How much truth was there in all this? How much was a calculated attempt to deceive him? He tried to break the spell by speaking, by breaking the smooth flow’ of her sentences. He said:

            “And once they could reach the stars, they did so and left the Earth. Some of us have guessed that.”

            “Then some of you have guessed wrong. Man tried to leave Earth. Unfortunately, however, we are not alone in the Galaxy. There are other stars with other planets, you know. There are even other intelligences. None, in this Galaxy at least, are as ancient as mankind, but in the 125,000 Centuries man remained on Earth, younger minds caught up and passed us, developed the interstellar drive, and colonized the Galaxy.

            “When we moved out into space, the signs were up. Occupied! No Trespassing! Clear Out! Mankind drew back its exploratory feelers, remained at home. But now he knew Earth for what it was: a prison surrounded by an infinity of freedom...And mankind died out!”

            Harlan said, “Just died out. Nonsense.”

            “They didn’t just die out. It took thousands of Centuries. There were ups and downs but, on the whole, there was a loss of purpose, a sense of futility, a feeling of hopelessness that could not be overcome. Eventually there was one last decline of the birth rate and finally, extinction. Your Eternity did that.”

            Harlan could defend Eternity now, the more intensely and extravagantly for having so shortly before attacked it so keenly. He said, “Let us at the Hidden Centuries and we will correct that. We have not failed yet to achieve the greatest good in those Centuries we could reach.”

            “The greatest good?” asked Noÿs in a detached tone that seemed to make a mockery of the phrase. “What is that? Your machines tell you. Your Computaplexes. But who adjusts the machines and tells them what to weigh in the balance? The machines do not solve problems with greater insight than men do, only faster. Only faster! Then what is it the Eternals consider good? I’ll tell you. Safety and security. Moderation. Nothing in excess. No risks without overwhelming certainty of an adequate return.”

            Harlan swallowed. With sudden force he remembered Twissell’s words in the kettle while talking about the evolved men of the Hidden Centuries. He said: “We bred out the unusual.”

            And wasn’t it so?

            “Well,” said Noÿs, “you seem to be thinking. Think of this, then. In the Reality that now exists, why is it that man is continually attempting space-travel and continually failing? Surely each space-travel era must know of previous failures. Why try again, then?”

            Harlan said, “I haven’t studied the matter.” But he thought uneasily of the colonies on Mars, established again and again, always failing. He thought of the odd attraction that spaceflight always had, even for Eternals. He could hear Sociologist Kantor Voy of the 2456th, sighing at the loss of electrogravitic spaceflight in one Century, and saying longingly: “It had been very beautiful.” And Life-Plotter Neron Feruque, who had sworn bitterly at its passing and had launched into a fit of railing at Eternity’s handling of anti-cancer serums to ease his spirit.

            Was there such a thing as an instinctive yearning on the part of intelligent beings to expand outward, to reach the stars, to leave the prison of gravity behind? Was it that which forced man to develop interplanetary travel dozens of times, forced him to travel over and over again to the dead worlds of a solar system in which only Earth was livable? Was it the eventual failure, the knowledge that one must return to the home prison, that brought about the maladjustments that Eternity was forever fighting. Harlan thought of the drug addiction in those same futile Centuries of the electrogravitics.

            Noÿs said, “In ironing out the disasters of Reality, Eternity rules out the triumphs as well, It is in meeting the great tests that mankind can most successfully rise to great heights, Out of danger and restless insecurity comes the force that pushes mankind to newer and loftier conquests, Can you understand that? Can you understand that in averting the pitfalls and miseries that beset man, Eternity prevents men from finding their own bitter and better solutions, the real solutions that come from conquering difficulty, not avoiding it.”

            Harlan began woodenly, “The greatest good of the greatest number--”

            Noÿs cut in, “Suppose Eternity had never been established?”

            “Well?”

            “I’ll tell you what would have happened. The energies that went into temporal engineering would have gone into nucleonics instead. Eternity would not have come but the interstellar drive would. Man would have reached the stars more than a hundred thousand Centuries before he did in this current Reality. The stars would then have been untenanted and mankind would have established itself throughout the Galaxy. We would have been first.”

            “And what would have been gained?” asked Harlan doggedly. “Would we be happier?”

            “Whom do you mean by ‘we’? Man would not be a world but a million worlds, a billion worlds. We would have the infinite in our grasp. Each world would have its own stretch of the Centuries, each its own values, a chance to seek happiness after ways of its own in an environment of its own. There are many happinesses, many goods, infinite variety.... That is the Basic State of mankind.”

            “You’re guessing,” said Harlan, and he was angry at himself for feeling attraction for the picture she had conjured, “How can you tell what would have happened?”

            Noÿs said, “You smile at the ignorance of the Timers who know only one Reality. We smile at the ignorance of the Eternals who think there are many Realities but that only one exists at a time.”

            “What does that gibberish mean?”

            “We don’t calculate alternate Realities. We view them. We see them in their state of non-Reality.”

            “A kind of ghostly never-never land where the might-have-beens play with the ifs,”

            “Without the sarcasm, yes.”

            “And how do you do that?”

            Noÿs paused, then said, “How can I explain that, Andrew? I have been educated to know certain things without really understanding all about them, just as you have. Can you explain the workings of a Computaplex? Yet you know it exists and works.”

            Harlan flushed. “Well, then?”

            Noÿs said, “We learned to view Realities and we found Basic State to be as I have described. We found, too, the Change that had destroyed Basic State. It was not any Change that Eternity had initiated; it was the establishment of Eternity itself--the mere fact of its existence. Any system like Eternity, which allows men to choose their own future, will end by choosing safety and mediocrity, and in such a Reality the stars are out of reach. The mere existence of Eternity at once wiped out the Galactic Empire.’ To restore it, Eternity must be done away with.

            “The number of Realities is infinite. The number of any subclass of Realities is also infinite. For instance, the number of Realities containing Eternity is infinite; the number in which Eternity does not exist is infinite; the number in which Eternity does exist but is abolished is also infinite. But my people chose from among the infinite a group that involved me.

            “I had nothing to do with that. They educated me for my job as Twissell and yourself educated Cooper for his job. But the number of Realities in which I was the agent in destroying Eternity was also infinite. I was offered a choice among five Realities that seemed least complex. I chose this one, the one involving you, the only Reality system involving you.”

            Harlan said, “Why did you choose it?”

            Noÿs looked away. “Because I loved you, you see. I loved you long before I met you.”

            Harlan was shaken. She said it with such depths of sincerity. He thought, sickly: She’s an actress

            He said, “That’s rather ridiculous.”

            “Is it? I studied the Realities at my disposal. I studied the Reality in which I went back to the 482nd, met first Finge, then you. The one in which you came to me and loved me, in which you took me into Eternity and the far up when of my own Century, in which you misdirected Cooper, and in which you and I, together, returned to the Primitive. We lived in the Primitive for the rest of our days. I saw our lives together and they were happy and I loved you. So it’s not ridiculous at all. I chose this alternative so that our love might be true.”

            Harlan said, “All this is false. It’s false. How can you expect me to believe you?” He stopped, then said suddenly, “Wait! You say you knew all this in advance? All that would happen?”

            “Yes.”

            “Then you’re obviously lying. You would have known that I would have you here at blaster point. You would have known you would fail. What is your answer to that?”

            She sighed lightly, “I told you there are an infinite number of any subclass of Realities. No matter how finely we focus on a given Reality it always represents an infinite number of very similar Realities. There are fuzzy spots. The finer we focus, the less fuzzy, but perfect sharpness cannot be obtained. The less fuzzy, the lower the probability of chance variation spoiling the result, but the probability is never absolutely zero. One fuzzy spot spoiled things.”

            “Which?”

            “You were to have come back to the far up when after the barrier at the 100,000th had been lowered and you did. But you were to have come back alone. It is for that reason that I was momentarily so startled at seeing Computer Twissell with you.”

            Again Harlan was troubled. How she made things fit in!

            Noÿs said, “I would have been even more startled, had I realized the significance of that alteration in full. Had you come alone, you would have brought me back to the Primitive as you did. Then, for love of humanity, for love of me, you would have left Cooper untouched. Your circle would have been broken, Eternity ended, our life together here safe.

            “But you came with Twissell, a chance variation. While coming, he talked to you of his thoughts about the Hidden Centuries and started you on a train of deductions that ended with your doubting my good faith. It ended with a blaster between us....And now, Andrew, that’s the story. You may blast me. There is nothing to stop you.”

            Harlan’s hand ached from its spastic grasp on the blaster. He shifted it dizzily to the other hand. Was there no flaw in her story? Where was the resolution he was to have gained from knowing certainly that she was a creature of the Hidden Centuries? He was more than ever tearing at himself in conflict, and dawn was approaching.

            He said, “Why two efforts to end Eternity? Why couldn’t Eternity have ended once and for all when I sent Cooper back to the 20th? Things would have ended then and there would not have been this agony of uncertainty.”

            “Because,” said Noÿs, “ending this Eternity is not enough. We must reduce the probability of establishing any form of Eternity to as near zero as we can manage. So there is lone thing we must do here in the Primitive. A small Change, a little thing. You know what a Minimum Necessary Change is like. It is only a letter to a peninsula called Italy here in the 20th. It is now the 19.32nd. In a few Centicentories, provided I send the letter, a man of Italy will begin experimenting with the neutronic bombardment of uranium.”

            Harlan found himself horrified. “You will alter Primitive history?”

            “Yes. It is our intention. In the new Reality, the final Reality, the first nuclear explosion will take place not in the 30th Century but in the 19.45th.”

            “But do you know the danger? Can you possibly estimate the danger?”

            “We know the danger. We have viewed the sheaf of resulting Realities. There is a probability, not a certainty, of course, that Earth will end with a largely radioactive crust, but before that--”

            “You mean there can be compensation for that?”

            “A Galactic Empire. An actual intensification of the Basic State.”

            “Yet you accuse the Eternals of interfering--”

            “We accuse them of interfering many times to keep mankind safely at home and in prison. We interfere, one, once, to turn him prematurely to nucleonics so that he might never, never, establish an Eternity.”

            “No,” said Harlan desperately. “There must be an Eternity.”

            “If you choose. It is yours to choose. If you wish to have psychopaths dictate the future of man--”

            “Psychopaths!” exploded Harlan.

            “Aren’t they? You know them. Think!”

            Harlan stared at her in outraged horror, yet he could not help thinking. He thought of Cubs learning the truth about Reality and Cub Latourette trying to kill himself as a result; Latourette had survived to become an Eternal with what scars on his personality none could say, yet helping to decide on alternate Realities.

            He thought of the caste system in Eternity, of the abnormal life that turned guilt feelings into anger and hatred against Technicians. He thought of Computers, struggling against themselves, of Finge intriguing against Twissell and Twissell spying on Finge. He thought of Sennor, fighting his bald head by fighting all the Eternals.

            He thought of himself.

            Then he thought of Twissell, the great Twissell, also breaking the laws of Eternity.

            It was as though he had always known Eternity to be all this. Why else should he have been so willing to destroy it? Yet he had never admitted it to himself fully; he had never looked it clearly in the face, until, suddenly, now.

            And he saw Eternity with great clarity as a sink of deepening psychoses, a writhing pit of abnormal motivation, a mass of desperate lives torn brutally out of context.

            He looked blankly at Noÿs.

            She said softly, “Do you see? Come to the mouth of the cave with me, Andrew.”

            He followed her, hypnotized, appalled at the completeness with which he had gained a new viewpoint. His blaster fell away from the line connecting it and Noÿs’s heart for the first time.

            The pale streakings of dawn grayed the sky, and the bulking kettle just outside the cave was an oppressive shadow against the pallor. Its outlines were dulled and blurred by the film thrown over it.

            Noÿs said, “This is Earth. Not the eternal and only home of mankind, but only a starting point of an infinite adventure. All you need do is make the decision. It is yours to make. You and I and the contents of this cave will be protected by a physiotime field against the Change. Cooper will disappear along with his advertisement; Eternity will go and the Reality of my Century, but we will remain to have children and grandchildren, and mankind will remain to reach the stars.”

            He turned to look at her, and she was smiling at him. It was Noÿs as she had been, and his own heart beating as it had used to.

            He wasn’t even aware that he had made his decision until the grayness suddenly invaded all the sky as the hulk of the kettle disappeared from against it.

            With that disappearance, he knew, even as Noÿs moved slowly into his arms, came the end, the final end of Eternity.

            --And the beginning of Infinity.