Arthur C. Clarke

"Something seems to have happened to the life-support system, Dave.”

Bowman took no notice. He was carefully studying the little labels on the logic units.

"I think there's been a failure in the pod-bay doors," Hal remarked conversationally. "Lucky you weren't killed.”

Bowman released the locking bar on the section labeled COGNITIVE FEEDBACK…

"Hey, Dave," said Hal. "What are you doing?”

He began to pull out the panel marked EGO-REINFORCEMENT.

"Look here, Dave," said Hal, "an irreplaceable amount of effort has gone into making me what I am.”

He started on the AUTO-INTELLECTION panel.

"Dave," said Hal, "I don't understand…

If TMA-1 had indeed sent a signal to the stars…humanity would have a breathing space which could certainly be measured in decades — more probably in centuries. To many people, this was a reassuring thought.

But not to all. A few scientists — most of them beachcombers on the wilder shores of theoretical physics — asked the disturbing question: "Are we certain that the speed of light is an unbreakable barrier?" They talked hopefully about shortcuts through higher dimensions, lines that were straighter than straight, and hyper-spatial connectivity. They were fond of using an expressive phrase coined by a Princeton mathematician of the last century: "Wormholes in space."

Discovery was no longer a happy 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…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.

Bowman's movement in the field of view must have triggered something in the unfathomable mind that was now ruling over the ship; for suddenly, Hal spoke.

"Too bad about Frank, isn't it?”

"Yes," Bowman answered, after a long pause. "It is.”

"I suppose you're pretty broken up about it?”

A few mystically inclined biologists speculated, taking their cues from the beliefs of many religions, that mind would eventually free itself from matter. The robot body, like the flesh-and-blood one, would be no more than a steppingstone to something which, long ago, men had called "spirit.”

And if there was anything beyond that, its name could only be God.

"Mission Control, this is X-ray-Delta-One. At two-zero-four-five, on-board fault prediction center in our niner-triple-zero computer showed Alpha Echo three five unit as probable failure within seventy-two hours. Request check your telemetry monitoring and suggest you review unit in your ship systems simulator. Also, confirm your approval our plan to go EVA and replace Alpha Echo three five unit prior to failure. Mission Control, this is X-ray-Delta-One, two-one-zero-three transmission concluded.”

Japetus alone possessed a distinctive geography, and a very strange one indeed. One hemisphere of the satellite was extremely dark, and showed very little surface detail. In complete contrast, the other was dominated by a brilliant white oval, about four hundred miles long and two hundred wide. At the moment, only part of this striking formation was in daylight, but the reason for Japetus's extraordinary variations in brilliance was now quite obvious.

Deliberate error was unthinkable. Even the concealment of truth filled him with a sense of imperfection, of wrongness — of what, in a human being, would have been called guilt. For like his makers, Hal had been created innocent; but, all too soon, a snake had entered his electronic Eden.

For the last hundred million miles, he had been brooding over the secret he could not share with Poole and Bowman…who would not learn the mission's full purpose, until there was need to know. So ran the logic of the planners; but their twin gods of Security and National Interest meant nothing to Hal. He was only aware of the conflict that was slowly destroying his integrity.

He was back, precisely where he wished to be, in the space that men called real.

"Hello, X-ray-Delta-One — this is Mission Control. We have completed the analysis of your AE-35 difficulty, and both our Hal Nine Thousands are in agreement…The trouble lies in the prediction circuits, and we believe that it indicates a programming conflict which we can only resolve if you disconnect your Nine Thousand and switch to Earth Control Mode. You will therefore take the following steps, beginning at 2200 Ship Time—”

The voice of Mission Control faded out. At the same moment, the Alert sounded, forming a wailing background to Hal's "Condition Yellow! Condition Yellow!”

"At the moment, we do not know whether to hope or fear. We do not know if, out on the moons of Saturn, you will meet with good or with evil — or only with ruins a thousand times older than Troy.”