2001: A Space Odyssey

by Arthur C. Clarke

  There must be wonders enough here for centuries of study; the first expedition could only carry out a preliminary reconnaissance. All that it found would be radioed back to Earth; even if the explorers never returned, their discoveries would not be lost.

  At the end of the hundred days, Discovery would close down. All the crew would go into hibernation; only the essential systems would continue to operate, watched over by the ship's tireless electronic brain. She would continue to swing around Saturn, on an orbit now so well determined that men would know exactly where to look for her a thousand years hence. But in only five years, according to present plans, Discovery II would come. Even if six or seven or eight years elapsed, her sleeping passengers would never know the difference. For all of them, the clock would have stopped as it had stopped already for Whitehead, Kaminski, and Hunter.

  Sometimes Bowman, as First Captain of Discovery, envied his three unconscious colleagues in the frozen peace of the Hibernaculum. They were free from all boredom and all responsibility; until they reached Saturn, the external world did not exist.

  But that world was watching them, through their bio-sensor displays. Tucked inconspicuously away among the massed instrumentation of the Control Deck were five small panels marked Hunter, Whitehead, Kaminski, Poole, Bowman. The last two were blank and lifeless; their time would not come until a year from now. The others bore constellations of tiny green lights, announcing that everything was well; and on each was a small display screen across which sets of glowing lines traced the leisurely rhythms that indicated pulse, respiration, and brain activity.

  There were times when Bowman, well aware how unnecessary this was—for the alarm would sound instantly if anything was wrong—would switch over to audio output. He would listen, half hypnotized, to the infinitely slow heartbeats of his sleeping colleagues, keeping his eyes fixed on the sluggish waves that marched in synchronism across the screen.

  Most fascinating of all were the EEG displays—the electronic signatures of three personalities that had once existed, and would one day exist again. They were almost free from the spikes and valleys, the electrical explosions that marked the activity of the waking brain—or even of the brain in normal sleep. If there was any wisp of consciousness remaining, it was beyond the reach of instruments, and of memory.

  This last fact Bowman knew from personal experience. Before he was chosen for this mission, his reactions to hibernation had been tested. He was not sure whether he had lost a week of his life—or whether he had postponed his eventual death by the same amount of time.

  When the electrodes had been attached to his forehead, and the sleep-generator had started to pulse, he had seen a brief display of kaleidoscopic patterns and drifting stars. Then they had faded, and darkness had engulfed him. He had never felt the injections, still less the first touch of cold as his body temperature was reduced to only a few degrees above freezing.

  He awoke, and it seemed that he had scarcely closed his eyes. But he knew that was an illusion; somehow, he was convinced that years had really passed.

  Had the mission been completed? Had they already reached Saturn, carried out their survey, and gone into hibernation? Was Discovery II here, to take them back to Earth?

  He lay in a dreamlike daze, utterly unable to distinguish between real and false memories. He opened his eyes, but there was little to see except a blurred constellation of lights which puzzled him for some minutes.

  Then he realized that he was looking at the indicator lamps on a Ship Situation Board, but it was impossible to focus on them. He soon gave up the attempt.

  Warm air was blowing across him, removing the chill from his limbs. There was quiet, but stimulating, music welling from a speaker behind his head. It was slowly growing louder and louder.

  Then a relaxed, friendly—but he knew computer generated—voice spoke to him.

  "You are becoming operational, Dave. Do not get up or attempt any violent movements. Do not try to speak."

  Do not get up! thought Bowman. That was funny. He doubted if he could wriggle a finger. Rather to his surprise, he found that he could.

  He felt quite contented, in a dazed, stupid kind of way. He knew dimly that the rescue ship must have come, that the automatic revival sequence had been triggered, and that soon he would be seeing other human beings. That was fine, but he did not get excited about it.

  Presently he felt hunger. The computer, of course, had anticipated this need.

  "There is a signal button by your right hand, Dave. If you are hungry, please press it."

  Bowman forced his fingers to hunt around, and presently discovered the pear-shaped bulb. He had forgotten all about it, though he must have known it was there. How much else had he forgotten: Did hibernation erase memory?

  He pressed the button, and waited. Several minutes later, a metal arm moved out from the bunk, and a plastic nipple descended toward his lips. He sucked on it eagerly, and a warm, sweet fluid coursed down his throat, bringing renewed strength with every drop.

  Presently it went away, and he rested once more. He could move his arms and legs now; the thought of walking was no longer an impossible dream.

  Though he felt his strength swiftly returning, he would have been content to lie here forever, if there had been no further stimulus from outside. But presently another voice spoke to him—and this time it was wholly human, not a construct of electrical pulses assembled by a more-than-human memory. It was also a familiar voice, though it was some time before he could recognize it

  "Hello, Dave. You're coming round fine. You can talk now. Do you know where you are?"

  He worried about this for some time. If he was really orbiting Saturn, what had happened during all the months since he had left Earth? Again he began to wonder if he was suffering from amnesia. Paradoxically, that very thought reassured him. If he could remember the word "amnesia" his brain must be in fairly good shape. . . .

  But he still did not know where he was, and the speaker at the other end of the circuit must have understood his situation completely.

  "Don't worry, Dave. This is Frank Poole. I'm watching your heart and respiration—everything is perfectly normal. Just relax—take it easy. We're going to open the door now and pull you out."

  Soft light flooded into the chamber; he saw moving shapes silhouetted against the widening entrance. And in that moment, all his memories came back to him, and he knew exactly where he was.

  Though he had come back safely from the furthest borders of sleep, and the nearest borders of death, he had been gone only a week. When he left the Hibernaculum, he would not see the cold Saturnian sky; that was more than a year in the future and a billion miles away. He was still in the trainer at the Houston Space Flight Center under the hot Texas sun.

  Chapter 16

  Hal

  But now Texas was invisible, and even the United States was hard to see. Though the low-thrust plasma drive had long since been closed down, Discovery was still coasting with her slender arrowlike body pointed away from Earth, and all her high-powered optical gear was oriented toward the outer planets, where her destiny lay.

  There was one telescope, however, that was permanently aimed at Earth. It was mounted like a gunsight on the rim of the ship's long-range antenna, and checked that the great parabolic bowl was rigidly locked upon its distant target. While Earth remained centered in the crosswires, the vital communication link was intact, and messages could come and go along the invisible beam that lengthened more than two million miles with every day that passed.

  At least once in every watch period Bowman would look homeward through the antenna-alignment telescope. As Earth was now far back toward the sun, its darkened hemisphere faced Discovery, and on the central display screen the planet appeared as a dazzling silver crescent, like another Venus.

  It was rare that any geographical features could be identified in that ever-shrinking arc of light, for cloud and haze concealed them, but even the darkened portion of the disk was endlessl
y fascinating. It was sprinkled with shining cities; sometimes they burned with a steady light, sometimes they twinkled like fireflies as atmospheric tremors passed over them.

  There were also periods when, as the Moon swung back and forth in its orbit, it shone down like a great lamp upon the darkened seas and continents of Earth. Then, with a thrill of recognition, Bowman could often glimpse familiar coastlines, shining in that spectral lunar light. And sometimes, when the Pacific was calm, he could even see the moonglow shimmering across its face; and he would remember nights beneath the palm trees of tropical lagoons.

  Yet he had no regrets for these lost beauties. He had enjoyed them all, in his thirty-five years of life; and he was determined to enjoy them again, when he returned rich and famous. Meanwhile, distance made them all the more precious.

  The sixth member of the crew cared for none of these things, for it was not human. It was the highly advanced HAL 9000 computer, the brain and nervous system of the ship.

  Hal (for Heuristically programmed ALgorithmic computer, no less) was a masterwork of the third computer breakthrough. These seemed to occur at intervals of twenty years, and the thought that another one was now imminent already worried a great many people.

  The first had been in the 1940s, when the long-obsolete vacuum tube had made possible such clumsy, high-speed morons as ENIAC and its successors. Then, in the 1960s, solid-state microelectronics had been perfected. With its advent, it was clear that artificial intelligences at least as powerful as Man's need be no larger than office desks—if one only knew how to construct them.

  Probably no one would ever know this; it did not matter. In the 1980s, Minsky and Good had shown how neural networks could be generated automatically—self replicated—in accordance with any arbitrary learning program. Artificial brains could be grown by a process strikingly analogous to the development of a human brain. In any given case, the precise details would never be known, and even if they were, they would be millions of times too complex for human understanding.

  Whatever way it worked, the final result was a machine intelligence that could reproduce—some philosophers still preferred to use the word "mimic"—most of the activities of the human brain, and with far greater speed and reliability. It was extremely expensive, and only a few units of the HAL 9000 series had yet been built; but the old jest that it would always be easier to make organic brains by unskilled labor was beginning to sound a little hollow.

  Hal had been trained for this mission as thoroughly as his human colleagues—and at many times their rate of input, for in addition to his intrinsic speed, he never slept. His prime task was to monitor the life-support systems, continually checking oxygen pressure, temperature, hull leakage, radiation, and all the other interlocking factors upon which the lives of the fragile human cargo depended. He could carry out the intricate navigational corrections, and execute the necessary flight maneuvers when it was time to change course. And he could watch over the hibernators, making any necessary adjustments to their environment and doling out the minute quantities of intravenous fluids that kept them alive.

  The first generations of computers had received their inputs through glorified typewriter keyboards, and had replied through high-speed printers and visual displays. Hal could do this when necessary, but most of his communication with his shipmates was by means of the spoken word. Poole and Bowman could talk to Hal as if he were a human being, and he would reply in the perfect idiomatic English he had learned during the fleeting weeks of his electronic childhood.

  Whether Hal could actually think was a question which had been settled by the British mathematician Alan Turing back in the 1940s. Turing had pointed out that, if one could carry out a prolonged conversation with a machine—whether by typewriter or microphone was immaterial—without being able to distinguish between its replies and those that a man might give, then the machine was thinking, by any sensible definition of the word. Hal could pass the Turing test with ease.

  The time might even come when Hal would take command of the ship. In an emergency, if no one answered his signals, he would attempt to wake the sleeping members of the crew, by electrical and chemical stimulation. If they did not respond, he would radio Earth for further orders.

  And then, if there was no reply from Earth, he would take what measures he deemed necessary to safeguard the ship and to continue the mission—whose real purpose he alone knew, and which his human colleagues could never have guessed.

  Poole and Bowman had often humorously referred to themselves as caretakers or janitors aboard a ship that could really run itself. They would have been astonished, and more than a little indignant, to discover how much truth that jest contained.

  Chapter 17

  Cruise Mode

  The day-by-day running of the ship had been planned with great care, and—theoretically at least—Bowman and Poole knew what they would be doing at every moment of the twenty-four hours. They operated on a twelve-hours-on, twelve-hours-off basis, taking charge alternately, and never being both asleep at the same time. The officer on duty remained on the Control Deck, while his deputy saw to the general housekeeping, inspected the ship, coped with the odd jobs that constantly arose, or relaxed in his cubicle.

  Although Bowman was nominal Captain on this phase of the mission, no outside observer could have deduced the fact. He and Poole switched roles, rank, and responsibilities completely every twelve hours. This kept them both at peak training, minimized the chances of friction, and helped toward the goal of 100 percent redundancy.

  Bowman's day began at 0600, ship's time—the Universal Ephemeris Time of the astronomers. If he was late, Hal had a variety of beeps and chimes to remind him of his duty, but they had never been used. As a test, Poole had once switched off the alarm; Bowman had still risen automatically at the right time.

  His first official act of the day would be to advance the Master Hibernation Timer twelve hours. If this operation was missed twice in a row, Hal would assume that both he and Poole had been incapacitated, and would take the necessary emergency action.

  Bowman would attend to his toilet, and do his isometric exercises, before settling down to breakfast and the morning's radio-fax edition of the World Times. On Earth, he never read the paper as carefully as he did now; even the smallest items of society gossip, the most fleeting political rumors, seemed of absorbing interest as it flashed across the screen.

  At 0700 he would officially relieve Poole on the Control Deck, bringing him a squeeze-tube of coffee from the kitchen. If—as was usually the case—there was nothing to report and no action to be taken, he would settle down to check all the instrument readings, and would run through a series of tests designed to spot possible malfunctions. By 1000 this would be finished, and he would start on a study period.

  Bowman had been a student for more than half his life; he would continue to be one until he retired. Thanks to the twentieth-century revolution in training and information-handling techniques, he already possessed the equivalent of two or three college educations—and, what was more, he could remember 90 percent of what he had learned.

  Fifty years ago, he would have been considered a specialist in applied astronomy, cybernetics, and space propulsion systems—yet he was prone to deny, with genuine indignation, that he was a specialist at all. Bowman had never found it possible to focus his interest exclusively on any subject; despite the dark warnings of his instructors, he had insisted on taking his Master's degree in General Astronautics—a course with a vague and woolly syllabus, designed for those whose IQs were in the low 130s and who would never reach the top ranks of their profession.

  His decision had been right; that very refusal to specialize had made him uniquely qualified for his present task. In much the same way Frank Poole—who sometimes disparagingly called himself "General Practitioner in space biology"—had been an ideal choice as his deputy. The two of them, with, if necessary, help from Hal's vast stores of information, could cope with any problems likely to ari
se during the voyage—as long as they kept their minds alert and receptive, and continually reengraved old patterns of memory.

  So for two hours, from 1000 to 1200, Bowman would engage in a dialogue with an electronic tutor, checking his general knowledge or absorbing material specific to this mission. He would prowl endlessly over ship's plans, circuit diagrams, and voyage profiles, or would try to assimilate all that was known about Jupiter, Saturn, and their far-ranging families of moons.

  At midday, he would retire to the galley and leave the ship to Hal while he prepared his lunch. Even here he was still fully in touch with events, for the tiny lounge-cum-dining room contained a duplicate of the Situation Display Panel, and Hal could call him at a moment's notice. Poole would join him for this meal, before retiring for his six-hour sleep period, and usually they would watch one of the regular TV programs beamed to them from Earth.

  Their menus had been planned with as much care as any part of the mission. The food, most of it freeze-dried, was uniformly excellent, and had been chosen for the minimum of trouble. Packets had merely to be opened and popped into the tiny auto-galley, which beeped for attention when the job was done. They could enjoy what tasted like—and, equally important, looked like—orange juice, eggs (any style), steaks, chops, roasts, fresh vegetables, assorted fruits, ice cream, and even freshly baked bread.

  After lunch, from 1300 to 1600 Bowman would make a slow and careful tour of the ship—or such part of it as was accessible. Discovery measured almost four hundred feet from end to end, but the little universe occupied by her crew lay entirely inside the forty-foot sphere of the pressure hull.