Clarke again made introductions. "General Gordon, Mr. Miles and Mr. Vickson. They'll be the pilot and observer."

The general acknowledged the introduction and asked: "How about the others? I understand the ship will take a full crew on its first flight."

"Once it's made a successful test flight-which Miles and Vickson will make with it-it will have a full crew for interplanetary explorations," Clarke said. "We're selecting and training the other members of the crew now."

The general took a backward step and ran his eye up the length of the hull. "Progress seems to have exceeded the estimates you made a year ago. How about the drive-is it installed yet?"

"It would have been if George hadn't taken things too literally again," Miles spoke up.

"George?" The general raised his eyebrows inquiringly and Clarke spoke to June.

"The general has never seen George. Go get him, will you?"

June walked across the room to the door marked a.s.sEMBLY 1 and Clarke said to Miles, "Go ahead, Tim-tell General Gordon what happened."

"It wasn't Vickson's fault," Miles began. "A man gets so accustomed to George being so intelligent and capable that he sometimes forgets and isn't specific enough-or in this case, Vickson was too specific. A human would have known what he wanted, but George-"

The door of a.s.sEMBLY 1 opened and Miles stopped talking as the general stared at the robot that was approaching them. It was a manlike monster of steel, seven feet tall and walked as silently as a cat on its rubber-soled feet. June walked beside it, a ridiculously tiny thing beside its own ponderous bulk.

"So that's George?" The general shook his head in amazement. "This is your new type robot, then? You've not only given it a manlike body, you've even given it almost-human features. In an alien sort of a way the thing is handsome."

"The almost-human face was purely by coincidence," Clarke explained. "It's D- Twenty-three brain is in its chest, of course, and it so happened that installing the eyes, ears and mouth gave it a head of normal size-that is, a head of a size normal for the size of its body."

The robot stopped a few feet in front of them and inclined its head downward so that its eyes were on theirs; eyes that were large and dark, giving it an appearance of thoughtful, patient waiting.

"Two eyes were necessary for it to properly estimate distances," Clarke explained.

"The rather humanlike ears are acoustically efficient and their location, together with locating the speaker grill at its mouth, was to enable it to do such things as use a phone."

"It phones?"

"Oh, yes. George can do anything. He checks data with the Master Computer at times-there's a line for that purpose-checks blueprints and installed circuits, a.s.sembles parts. He is very useful and, since he never gets tired or needs sleep, he works twenty- four hours a day."

"Hm-m-m." General Gordon studied the robot thoughtfully. "Apparently we'll have no trouble training the D-Twenty-three's for duty in the Air Corps."

"Well, they will have to be trained, and under the supervision of Center technicians. Mr. Miles' account of what happened last night will show you why."

"Oh, yes-the trouble with the robot. Please go on, Mr. Miles, and tell us what happened."

June looked inquiringly at Clarke. He nodded and she said to the robot, "They're through with you, George-get on back to work." It turned without a word and walked across the room and through the door of a.s.sEMBLY 1.

"It started just as Vickson here went off-shift," Miles began. "Vickson was working on the final a.s.sembly of the drive and came to the K-Seven reflector at the end of his shift. It's a very essential little item, though its installation is simple. But it had to be coated with the Reuther Alloy, first. This reflector is a circular plate of platinum, eight inches in diameter, and we were to do the alloy plating here-they sent us a special machine for that, yesterday. The alloy has to be of a certain thickness-sixty-five one- thousandths of an inch. So, as Vickson went off-shift, he gave George the plate and told him to metal-spray it to a thickness of sixty-five one-thousandths of an inch.

"This alloy is so hard to produce and so expensive that we had orders to waste none of it, if possible. Vickson ordered George to use the only method possible whereby the proper thickness would be put on the plate in one operation, with no guesswork and no surplus to machine off; he told George to determine the surface area of the plate then weigh out the proper amount of alloy to coat it the required thickness. This should have been a simple job, quickly done, and George was to then install the plate-a job even simpler. The entire thing shouldn't have taken George over twenty minutes.

"When I came to work an hour later I took it for granted everything had been done. I had the workmen put in the drive shields and I went ahead with circuits in the control panel. I was a fool not to check with George, first, but it's like I said; George is so intelligent and competent that you sometimes forget he isn't human. It was six hours later that I went into the a.s.sembly room, over there, to see why he hadn't brought out the parts he was supposed to be a.s.sembling."

Miles breathed deeply, and sighed. "He wasn't at his workbench. He was at the blueprint table, figuring. He had a pile of papers beside him ten inches high, all covered with figures. The K-Seven reflector plate was over by the sprayer, not even touched-"

Clarke interrupted him. "For General Gordon to understand the peculiarities to be expected from D-Twenty-three's, we had better let Vickson tell us his exact words to George."

"It was stupid of me," Vickson said, almost apologetically. "I made the mistake of giving him a specific order and expecting him to follow it as a human would have-to a certain degree of precision and no farther. My words were: 'Take a pencil and paper and determine the exact surface area of this plate, then weigh out the proper amount of alloy to coat it sixty-five one-thousandths of an inch.'

"A human would have determined the area by the formula: Point seven eight five four times the squared diameter. Although not exact, it's close enough. But I had told George to determine the exact area of the plate and that's what he was trying to do, using the other formula: pi times the squared diameter, divided by four. He would still be at it if Miles hadn't stopped him." "Why?" the general asked. "The formulas are the same."

"No-" Vickson shook his head. "In the first one, a human has already decided how far the decimal of pi should be carried. This, though close enough, is not exact. I had told George to determine the exact area of the plate, and to do so he had to use the second formula which contains pi as an endless term."

"But that's absurd!" the general objected. "You claim a robot is intelligent-didn't it know it could never find the last decimal place of pi?"

"George knew, but he was simply following orders," Clarke said. "The duty of a machine is to obey orders, not place special interpretations on them."

"And you had to have the drive shields taken off again?" Knight asked Miles. "Is the plate sprayed, now?"

"It took George no more than five minutes after I told him to use the point seven eight five four formula," Miles replied, "but we lost the entire shift on that part of the ship, due to his cussed attention to detail."

The general frowned thoughtfully. "Why not teach it to understand the purpose of this ship as a whole, as well as the purpose of the ship's component parts?" he asked. "The entire thing is very simple: We want a s.p.a.ceship. We want it equipped with an efficient drive plus disintegrator rays for protection against meteors. We want all this accomplished as soon as possible. Surely, as intelligent as it is, it can comprehend the purpose of the work-the ultimate goal-and learn better than to repeat any such off-on- a-tangent idiocy as this pi business."

"How do we explain 'purpose' to it?" Clarke asked. "A machine understands only 'Is'

and 'Is not'-it can't understand human desires and purposes since they are based on 'I want it to be' and not on 'Is' and 'Is not.' "

"Well-you should know if it's impossible," the general said, but he did not sound entirely convinced.

"We have a slogan-a philosophy, you might say. Mr. Knight suggested it several years ago and we have it plastered on the Master Computer, itself, to keep us reminded of the gulf that will always separate Man from Machine. You saw it, general-a simple little five-word sentence."

"I remember it. It seems to me you're exaggerating the importance of it, but I'm a military man and certainly in no position to argue the characteristics of robots with the men who created them." He looked up at the ship again and changed the subject. "Are the disintegrator ray projectors installed?"

"Not yet," Clarke answered. "We've given the Computer the job of devising a safety gadget that will prevent the operation of the ray projectors whenever the ship is within an atmosphere dense enough to produce a feedback of the rays."

"Although the situation is looking less and less like war, you can never tell," the general said. "The disintegrators would serve as a terrible threat of retaliation. However, rather than having the rays as a strictly offensive weapon used from a s.p.a.ceship, it would be more desirable to have ray projectors mounted along the borders of this country. They would make the perfect defense weapon-no force by air, land or water could get past them." "Except for the feedback," Clarke said.

"Except for the feedback-and I know without asking that you haven't been able to do anything about it."

"This chain-reaction feedback is a tough problem. We haven't solved it yet. The projector actually projects two rays, which you might call A and B. They merge at a point about twenty feet in front of the projector and disa.s.sociate the atomic structure of any material in their path from there on. The maximum range is controllable, however. In empty s.p.a.ce, A and B are harmless-until they unite. But there's the chain-reaction feedback within an atmosphere and the disa.s.sociating effects of combined A and B follows the ununited A and B rays to their source-the ray generator. The result is that the ship, and any material within a radius of one hundred feet, is transformed suddenly into a cloud of disa.s.sociated atoms. It was designed for protection against meteors in s.p.a.ce, where there would be no feedback."

"I hope we never have to use it against anything but meteors," the general said. "I'm a military man and the competent military leader wants a permanent victory. Should war ever come, we must avert defeat at all costs but a victory won with the disintegrator rays, projected from a ship in s.p.a.ce, would only sow the hatred for another war."

"Why do you say that?" Knight asked.

"It's a human characteristic to say of defeat at the hands of an enemy no better armed than you-and with greatly varying degrees of philosophical acceptance-'The fortunes of war.' But Russo-Asia's defeat by a disintegrator ray, projected from an invulnerable ship in s.p.a.ce, would arouse the reaction: 'It wasn't a fair fight-we never had a chance.'

Victory would be ours, but victory by such a means would create a resentment and hatred that would be long in dying."

"I can see your point, general," Knight said. "But you do intend to use the disintegrator if necessary, don't you?"

"We don't want to have to use it, but we certainly shall if we're forced to," the general answered. He smiled faintly and added: "There's an old saying, and a true one: 'The very worst peace is better than the very best war.' To that should be added an equally true fact: 'The very worst victory is better than the very best defeat.' "

He looked at his watch, then at Clarke. "I'm afraid my time is running short, and I'd like to look through the ship before I go."

"Of course," Clarke said. He turned to Knight. "I'm sorry this came up to spoil your day, but we have to make up for the time George lost us. If you'll make the check of the SD-FA blueprints, with Miss Martin's a.s.sistance, we'll have the lost time made up by night. By the way"-he looked toward the a.s.sEMBLY 1 door-"where did Miss Martin go?"

"She's in with George, I think," Knight said.

"Probably already checking her share of the work," Clarke said with an approving nod. "You have a superb a.s.sistant in Miss Martin."

The four of them went into the ship and Knight walked across the concrete floor to the door of the a.s.sembly room, smiling at Clarke's statement. June was a superb a.s.sistant, despite her youth, but she was hardly the type to exercise her abilities when less important and more interesting things could be found to do.

He opened the door to find her, as he had expected, busily pestering the stoic George.

"Don't you understand that one, either?" she was asking. "Tell me what the point is."

George answered her without pausing in his deft a.s.sembly of the work on the bench before him. "I understand it. It can be interpreted in either of two ways; as an expression of a feeling of pleasure or as a factual statement of the loss of the ability to phosph.o.r.esce."

"What goes on?" Knight asked.

"I've been trying to develop a sense of humor in George," she said, making a face at the unmoved robot. "I told him jokes and explained the points, but it's a waste of time. He just can't see the funny side of anything."

"You ought to know better than to even try. What kind of jokes did you tell him, anyway? What was this one about not being able to phosph.o.r.esce?"

"What the firefly said when he got his tail cut off-'I'm delighted!' "

"Oh." Knight pulled his mouth down and shuddered. "No wonder George refused to laugh at that. Not even the most genial human-being could see anything funny about such a stup-"

"Never mind!" she interrupted him. "I think it's funny." She looked toward the doorway. "Where did the bra.s.s go?"

"Up into the ship. You and I are to check these blueprints. You can check the electronic circuits of the initial and restraining stages and I'll take the rest."

"Well-" she sighed philosophically, "at least I know what I'll be doing the rest of the day-and it's all the fault of that humorless pile of tin."

"Speaking of jokes"-Knight spilled the blueprints out of the brown envelope and spread them on the table-"did I ever tell you about the traveling salesman who asked the farmer's daughter if-"

"Never mind that, either!" she interrupted him firmly. "Do you want to shock George?"

4.

Silence.

There had been utter silence from the first; the silence enclosing him and the dark eyes watching him. Why did the doctor move so quietly? Was it because he was dying; was it because people always walk softly in the presence of the dying?

Of course! His doctor was showing him the respect that is due the dead-and the soon-to-be-dead.

For a moment the tide of insanity almost broke through the bulwark built around his mind by the antihysteria drugs; the insanity he so desperately longed for; the insanity that would let him die in mindless, unfrightened madness.

The words above the pilot's communication panel now read: OBSERVER HAS A LIFE EXPECTANCY OF TWENTY HOURS AT PRESENT ACCELERATION.

DEATH FOR OBSERVER WILL RESULT UNLESS ACCELERATION IS REDUCED.

WITHIN THAT PERIOD.

The urge to laugh came to him. It was funny! The doctor wouldn't reduce the acceleration until he gave the order and he couldn't give the order until the doctor reduced the acceleration.

Funny! The b.u.t.terscotchmen couldn't run unless they were hot and couldn't get hot unless they ran . . . Couldn't run unless they were hot-Couldn't get hot unless they ran .

. . Couldn't run-Couldn't hot . . . run . . . hot . . . run . . . hot . . . vicious circles and circles vicious, spinning around and around . . . spin around and around and around and around till your mind flies off into the darkness where someone is laughing . . . How pleasant to go laughing and spinning into the darkness, around and around . . . laughing and spinning and spinning and laughing . . . around and around and . . .

Sanity jolted into his mind with all its cold, grim reality and the comfort of the brief delirium vanished. The doctor was standing over him, injecting the antihysteria drug into his bloodstream.

The desperate fear ran through him again, terrible in its helpless impotency. It was always the same; the doctor watched him ceaselessly, ready to move forward and deny him the solace of madness at the first sign of its coming.

The doctor didn't hate him-WHY MUST THE DOCTOR TORTURE HIM SO? * * *

It was a year later, with the ship six days from the morning of its test flight, that Russo-Asia completed the about-face in its foreign policy and promised the freedom of Western representatives to inspect their "greatly reduced military strength." It was not, to Knight, a surprising or mysterious thing. Russo-Asia had been built on false promises and deceit; this last action, he feared, could have but one reason behind it.

It was the other, happening five days later, that sent the chill certainty, too late, into his mind-the discovery that a tentacle of Cullin's presumably dead espionage system was in the very heart of Center . . .

It was with relief that Knight led General Gordon and his five-star superior, General Marker, to the control room of the ship. He had shown them the ship from bottom to top, explaining its workings and answering questions until he was beginning to feel like a tourist's guide. Furthermore, it was late in the night-or early in the morning, rather-and he would have little sleep before returning to be on hand for the ship's first take-off.

"And this is the control room," he said. "The first seat, with its control and instrument board over there, is for the pilot. This one is for the observer." He indicated the seat and instrument board immediately behind the pilot's. "You'll notice the observer has only a few instruments, but several viewscreens. The pilot can control the ship manually, with those b.u.t.tons on his control board, or by voice command to the robot drive control-a D- Twenty-three. In an emergency, the observer can control the ship by voice command to the drive control, but his panel is not equipped with manual control b.u.t.tons. The observer's duties are to observe and record, as well as to maintain constant contact with Earth."

He pointed to a small viewscreen in the center of the observer's panel. "This is his contact with the auxiliary control station. You both saw it-that little steel building two hundred feet west of this one. A man will be on duty at all times in it." He flipped a switch and the screen came to life, to show the back of an empty chair and a steel door beyond. "No one on duty right now, of course, but there will be when the ship takes off."

"What is the purpose of this ground-control station?" General Marker asked. "I know, of course, that it's an auxiliary means of controlling the ship, but why?"

"It's a safety measure we hope we won't have any need for. We're convinced that the ship has no bugs, but we don't want to take any chances with men's lives. So we have the constant communication with the observer plus the auxiliary control of the ship's drive.

Should something go wrong, such as both pilot and observer becoming unconscious, we can bring the ship safely back to Earth from our ground-control station."

"Which method of controlling the ship takes precedence, the pilot's manual control, his oral orders to the drive control, or the means of controlling the ship from the ground- control station?"

"The control from the ground overrides all forms of control from within the ship. It might possibly be that a man would crack, and if he did he might give any kind of orders to the robot drive control-even such a one as ordering the disintegrators turned on Earth.

We don't expect anything like that to happen, you understand-Miles and Vickson were selected for their mental stability-but we like to play safe."