"I'm afraid I will have to ask you to leave the Administration area," the Office Manager said coldly. "Except for necessary business, it is out of bounds for Freemen." Hendley stared at him in stunned disbelief. It was incredible that the man would not remember him--even more inconceivable that he would attach no plausibility whatever to Hendley's story. Numbers were all that mattered--the set of symbols setting forth a man's identity, establishing his status, certifying his existence, a combination filed away in an electronic brain which could, on demand, reveal who and what a man was. "You've got to listen to me," Hendley said with an effort for control. "I'm Thomas Robert Hendley. TRH-247. I'm not a Freeman. There's been a switch--" "I'm sorry, sir," the beige-clad official said in brisk tones that contained no sorrow, only a curt dismissal. "Our computers do not make mistakes." Hendley backed away. The unknown, unnameable terror shook him. It was the demoralizing fear which might have been felt by some very clever, almost human machine which had been taught every emotion a man could feel except this one, and which, confronted with the unknown, began to clash and grind to a halt, stripping its intricate gears, shattering its neatly made cogs and bolts, flying into a thousand pieces, until it was no longer an almost human machine, but merely a collection of unidentifiable pieces of something that did not exist any more. Terrorized by a glimpse of non-existence, Hendley burst from the administration building and ran across the cool, wet, and slippery grass toward the beckoning shadows of a grove of trees. * * * * * Hendley crouched at the edge of the woods where a low growth of bushes crowding against tree trunks was dense enough to hide even a white uniform. All day he had loitered in the woods, at first in dumb panic, later in despair, and at last with a growing determination. He had spent the afternoon measuring the depth of the grove, verifying the fact that it followed the exterior wall of the camp along its entire length, following each footpath to see where it led--and watching the wall. He had learned several facts he had not known before. The wall was patrolled by robots. Its surface was somehow sensitized, the slightest touch setting off an unheard alarm which in less than a minute brought mobile robots trundling along the wide, flat top of the wall. The interior surface of the wall, unlike the outside, was well maintained. There were no cracks, no soft crumbling places to provide holds for hand or foot. A group of men might have made a human pyramid, from which the topmost man could have reached the top of the wall. But before this feat could have been accomplished, a robot would have appeared with silent efficiency. Hendley did not know what action the robot-guards would take, but it was certain that they would have been trained to act firmly and decisively. Resistance would be futile.