Expedition to Earth

  Arthur C. Clarke

  Copyright

  Expedition to Earth

  Copyright © 1953 by Arthur C. Clarke

  Cover art to the electronic edition copyright © 2012 by RosettaBooks, LLC.

  All rights reserved. No part of this book may be used or reproduced in any form or by any electronic or mechanical means, including information storage and retrieval systems, without permission in writing from the publisher, except by a reviewer who may quote brief passages in a review.

  Electronic edition published 2012 by RosettaBooks, LLC, New York.

  ISBN Mobipocket edition: 9780795325373

  To Walter Gillings

  —who must share much of the blame.

  Contents

  Second Dawn

  “If I Forget Thee, Oh Earth…”

  Breaking Strain

  History Lesson

  Superiority

  Exile of the Eons

  Hide and Seek

  Expedition to Earth

  Loophole

  Inheritance

  The Sentinel

  Second Dawn

  “Here they come,” said Eris, rising to his forefeet and turning to look down the long valley. For a moment the pain and bitterness had left his thoughts, so that even Jeryl, whose mind was more closely tuned to his than to any other, could scarcely detect it. There was even an undertone of softness that recalled poignantly the Eris she had known in the days before the War—the old Eris who now seemed almost as remote and as lost as if he were lying with all the others out there on the plain.

  A dark tide was flowing up the valley, advancing with a curious, hesitant motion, making odd pauses and little bounds forward. It was flanked with gold—the thin line of the Atheleni guards, so terrifyingly few compared with the black mass of the prisoners. But they were enough: indeed, they were only needed to guide that aimless river on its faltering way. Yet at the sight of so many thousands of the enemy, Jeryl found herself trembling and instinctively moved toward her mate, silver pelt resting against gold. Eris gave no sign that he had understood or even noticed the action.

  The fear vanished as Jeryl saw how slowly the dark flood was moving forward. She had been told what to expect, but the reality was even worse than she had imagined. As the prisoners came nearer, all the hate and bitterness ebbed from her mind, to be replaced by a sick compassion. No one of her race need evermore fear the aimless, idiot horde that was being shepherded through the pass into the valley it would never leave again.

  The guards were doing little more than urge the prisoners on with meaningless but encouraging cries, like nurses calling to infants too young to sense their thoughts. Strain as she might, Jeryl could detect no vestige of reason in any of those thousands of minds passing so near at hand. That brought home to her, more vividly than could anything else, the magnitude of the victory—and of the defeat. Her mind was sensitive enough to detect the first faint thoughts of children, hovering on the verge of consciousness. The defeated enemy had become not even children, but babies with the bodies of adults.

  The tide was passing within a few feet of them now. For the first time, Jeryl realized how much larger than her own people the Mithraneans were, and how beautifully the light of the twin suns gleamed on the dark satin of their bodies. Once a magnificent specimen, towering a full head above Eris, broke loose from the main body and came blundering toward them, halting a few paces away. Then it crouched down like a lost and frightened child, the splendid head moving uncertainly from side to side as if seeking it knew not what. For a moment the great, empty eyes fell full upon Jeryl’s face. She was as beautiful, she knew, to the Mithraneans as to her own race—but there was no flicker of emotion on the blank features, and no pause in the aimless movement of the questing head. Then an exasperated guard drove the prisoner back to his fellows.

  “Come away,” Jeryl pleaded. “I don’t want to see any more. Why did you ever bring me here?” The last thought was heavy with reproach.

  Eris began to move away over the grassy slopes in great bounds that she could not hope to match, but as he went his mind threw its message back to hers. His thoughts were still gentle, though the pain beneath them was too deep to be concealed.

  “I wanted everyone—even you—to see what we had to to do to win the War. Then, perhaps, we will have no more in our lifetimes.”

  He was waiting for her on the brow of the hill, undistressed by the mad violence of his climb. The stream of prisoners was now too far below for them to see the details of its painful progress. Jeryl crouched down beside Eris and began to browse on the sparse vegetation that had been exiled from the fertile valley. She was slowly beginning to recover from the shock.

  “But what will happen to them?” she asked presently, still haunted by the memory of that splendid, mindless giant going into a captivity it could never understand.

  “They can be taugh how to eat,” said Eris. “There is food in the valley for half a year, and then we’ll move them on. It will be a heavy strain on our own resources, but we’re under a moral obligation—and we’ve put it in the peace treaty.”

  “They can never be cured?”

  “No. Their minds have been totally destroyed. They’ll be like that until they die.”

  There was a long silence. Jeryl let her gaze wander across the hills, falling in gentle undulations to the edge of the ocean. She could just make out, beyond a gap in the hills, the distant lines of blue that marked the sea—the mysterious, impassable sea. Its blue would soon be deepening into darkness, for the fierce white sun was setting and presently there would only be the red disk—hundreds of times larger but giving far less light—of its pale companion.

  “I suppose we had to do it,” Jeryl said at last. She was thinking almost to herself, but she let enough of her thoughts escape for Eris to overhear.

  “You’ve seen them,” he answered briefly. “They were bigger and stronger than we. Though we outnumbered them, it was a stalemate: in the end, I think they would have won. By doing what we did, we saved thousands from death—or mutilation.”

  The bitterness came back into his thoughts, and Jeryl dared not look at him. He had screened the depths of his mind, but she knew that he was thinking of the shattered ivory stump upon his forehead. The War had been fought, except at the very end, with two weapons only—the razor-sharp hoofs of the little, almost useless forepaws, and the unicorn-like horns. Without one of these, Eris could never fight again, and from the loss stemmed much of the embittered harshness that sometimes made him hurt even those who loved him.

  Eris was waiting for someone, though who it was Jeryl could not guess. She knew better than to interrupt his thoughts while he was in his present mood, and so remained silently beside him, her shadow merging with his as it stretched far along the hilltop.

  Jeryl and Eris came of a race which, in Nature’s lottery, had been luckier than most—and yet had missed one of the greatest prizes of all. They had powerful bodies and powerful minds, and they lived in a world which was both temperate and fertile. By human standards, they would have seemed strange but by no means repulsive. Their sleek, fur-covered bodies tapered to a single giant rearlimb that could send them leaping over the ground in thirty-foot bounds. The two forelimbs were much smaller, and served merely for support and steadying. They ended in pointed hoofs that could be deadly in combat, but had no other useful purpose.

  Both the Atheleni and their cousins, the Mithraneans, possessed mental powers that had enabled them to develop a very advanced mathematics and philosophy: but over the physical world they had no control at all. Houses, tools, clothes—indeed, artifacts of any kind—were utterly unknown to them. To races which possessed hands, tentacles, or oth
er means of manipulation, their culture would have seemed incredibly limited: yet such is the adaptability of the mind, and the power of the commonplace, that they seldom realized their handicaps and could imagine no other way of life. It was natural to wander in great herds over the fertile plains, pausing where food was plentiful and moving on again when it was exhausted. This nomadic life had given them enough leisure for philosophy and even for certain arts. Their telepathic powers had not yet robbed them of their voices and they had developed a complex vocal music and an even more complex choreography. But they took the greatest pride of all in the range of their thoughts: for thousands of generations they had sent their minds roving through the misty infinities of metaphysics. Of physics, and indeed of all the sciences of matter, they knew nothing—not even that they existed.

  “Someone’s coming,” said Jeryl suddenly. “Who is it?”

  Eris did not bother to look, but there was a sense of strain in his reply.

  “It’s Aretenon. I agreed to meet him here.”

  “I’m so glad. You were such good friends once—it upset me when you quarreled.”

  Eris pawed fretfully at the turf, as he did when he was embarrassed or annoyed.

  “I lost my temper with him when he left me during the fifth battle of the Plain. Of course I didn’t know then why he had to go.”

  Jeryl’s eyes widened in sudden amazement and understanding.

  “You mean—he had something to do with the Madness, and the way the War ended?”

  “Yes. There were very few people who knew more about the mind than he did. I don’t know what part he played, but it must have been an important one. I don’t suppose he’ll ever be able to tell us much about it.”

  Still a considerable distance below them, Aretenon was zigzagging up the hillside in great leaps. A little later he had reached them, and instinctively bent his head to touch horns with Eris in the universal gesture of greeting. Then he stopped, horribly embarrassed, and there was an awkward pause until Jeryl came to the rescue with some conventional remarks.

  When Eris spoke, Jeryl was relieved to sense his obvious pleasure at meeting his friend again, for the first time since their angry parting at the height of the War. It had been longer still since her last meeting with Aretenon, and she was surprised to see how much he had changed. He was considerably younger than Eris—but no one would have guessed it now. Some of his once-golden pelt was turning black with age, and with a flash of his old humor Eris remarked that soon no one would be able to tell him from a Mithranean.

  Aretenon smiled.

  “That would have been useful in the last few weeks. I’ve just come through their country, helping to round up the wanderers. We weren’t very popular, as you might expect. If they’d known who I was, I don’t suppose I’d have got back alive—armistice or no armistice.”

  “You weren’t actually in charge of the Madness, were you?” asked Jeryl, unable to control her curiosity.

  She had a momentary impression of thick, defensive mists forming around Aretenon’s mind, shielding all his thoughts from the outer world. Then the reply came, curiously muffled, and with a sense of distance that was very rare in telepathic contact.

  “No: I wasn’t in supreme charge. But there were only two others between myself and—the top.”

  “Of course,” said Eris, rather petulantly, “I’m only an ordinary soldier and don’t understand these things. But I’d like to know just how you did it. Naturally,” he added, “neither Jeryl nor myself would talk to anyone else.”

  Again that veil seemed to descend over Aretenon’s thoughts. Then it lifted, ever so slightly.

  “There’s very little I’m allowed to tell. As you know, Eris, I was always interested in the mind and its workings. Do you remember the games we used to play, when I tried to uncover your thoughts, and you did your best to stop me? And how I sometimes made you carry out acts against your will?”

  “I still think,” said Eris, “that you couldn’t have done that to a stranger, and that I was really unconsciously co-operating.”

  “That was true then—but it isn’t any longer. The proof lies down there in the valley.” He gestured toward the last stragglers who were being rounded up by the guards. The dark tide had almost passed, and soon the entrance to the valley would be closed.

  “When I grew older,” continued Aretenon, “I spent more and more of my time probing into the ways of the mind, and trying to discover why some of us can share our thoughts so easily, while others can never do so but must remain always isolated and alone, forced to communicate by sounds or gestures. And I became fascinated by those rare minds that are completely deranged, so that those who possess them seem less than children.

  “I had to abandon these studies when the War began. Then, as you know, they called for me one day during the fifth battle. Even now, I’m not quite sure who was responsible for that. I was taken to a place a long way from here, where I found a little group of thinkers, many of whom I already knew.

  “The plan was simple—and tremendous. From the dawn of our race we’ve known that two or three minds, linked together, could be used to control another mind, if it were willing, in the way that I used to control yours. We’ve employed this power for healing since ancient times. Now we planned to use it for destruction.

  “There were two main difficulties. One was bound up with that curious limitation of our normal telepathic powers—the fact that, except in rare cases, we can only have contact over a distance with someone we already know, and can communicate with strangers only when we are actually in their presence.

  “The second, and greater problem, was that the massed power of many minds would be needed, and never before had it been possible to link together more than two or three. How we succeeded is our main secret: like all such things, it seems easy now it has been done. And once we had started, it was simpler than we had expected. Two minds are more than twice as powerful as one, and three are much more than thrice as powerful as a single will. The exact mathematical relationship is an interesting one. You know how very rapidly the number of ways a group of objects may be arranged increases with the size of the group? Well, a similar relationship holds in this case.

  “So in the end we had our Composite Mind. At first it was unstable, and we could hold it together for only a few seconds. It’s still a tremendous strain on our mental resources, and even now we can only do it for—well, for long enough.

  “All these experiments, of course, were carried out in great secrecy. If we could do this, so could the Mithraneans, for their minds are as good as ours. We had a number of their prisoners, and we used them as subjects.”

  For a moment the veil that hid Aretenon’s inner thoughts seemed to tremble and dissolve: then he regained control.

  “That was the worst part. It was bad enough to send madness into a far land, but it was infinitely worse when you could watch with your own eyes the effects of what you did.

  “When we had perfected our technique, we made the first long-distance test. Our victim was someone so well-known to one of our prisoners—whose mind we had taken over—that we could identify him completely and thus the distance between us was no objection. The experiment worked, but of course no one suspected that we were responsible.

  “We did not operate again until we were certain that our attack would be so overwhelming that it would end the War. From the minds of our prisoners we had identified about a score of Mithraneans—their friends and kindred—in such detail that we could pick them out and destroy them. As each mind fell beneath our attack, it gave up to us the knowledge of others, and so our power increased. We could have done far more damage than we did, for we took only the males.”

  “Was that,” asked Jeryl bitterly, “so very merciful?”

  “Perhaps not: but it should be remembered to our credit. We stopped as soon as the enemy sued for peace, and, as we alone knew what had happened, we went into their country to undo what damage we could. It was little enough.??
?

  There was a long silence. The valley was deserted now, and the white sun had set. A cold wind was blowing over the hills, passing, where none could follow it, out across the empty and untraveled sea. Then Eris spoke his thoughts almost whispering to Aretenon’s mind.

  “You did not come to tell me this, did you? There is something more.” It was a statement rather than a query.

  “Yes,” replied Aretenon. “I have a message for you—one that will surprise you a good deal. It’s from Therodimus.”

  “Therodimus! I thought—”

  “You thought he was dead, or worse still, a traitor. He’s neither, although he’s lived in enemy territory for the last twenty years. The Mithraneans treated him as we did, and gave him everything he needed. They recognized his mind for what it was, and even during the War no one touched him. Now he wants to see you again.”

  Whatever emotions Eris was feeling at this news of his old teacher, he gave no sign of them. Perhaps he was recalling his youth, remembering now that Therodimus had played a greater part in the shaping of his mind than had any other single influence. But his thoughts were barred to Aretenon and even to Jeryl.

  “What’s he been doing all this time?” Eris asked at length. “And why does he want to see me now?”

  “It’s a long and complicated story,” said Aretenon, “but Therodimus has made a discovery quite as remarkable as ours, and one that may have even greater consequences.”

  “Discovery? What sort of discovery?”

  Aretenon paused, looking thoughtfully along the valley. The guards were returning, leaving behind only the few who would be needed to deal with any wandering prisoners.

  “You know as much of our history as I do, Eris,” he began. “It took, we believe, something like a million generations for us to reach our present level of development—and that’s a tremendous length of time! Almost all the progress we’ve made has been due to our telepathic powers: without them we’d be little different from all those other animals that show such puzzling resemblances to us. We’re very proud of our philosophy and our mathematics, of our music and dancing—but have you ever thought, Eris, that there might be other lines of cultural development which we’ve never even dreamed of? That there might be other forces in the Universe besides mental ones?”