'But they are getting together! We're helping them to do so. We're ordering them to do so. Our scientists visit the other side, Breckenridge. They visit Them regularly. You made a point of how strange it was that no one in robotics did. Well, ten of those scientists are still there and in their place, ten humanoids are converging on Cheyenne.'

  'That's a ridiculous guess.'

  'I think it's a good one, Breckenridge. But it wouldn't work unless we knew humanoids were in America so that we would call the conference in the first place. Quite a coincidence that you brought the news of the humanoids and suggested the conference and suggested the agenda and are running the show and know exactly which scientists were invited. Did you make sure the right ten were in­cluded?'

  'Dr. Lynn!' cried Breckenridge in outrage. He poised to rush forward.

  Lynn said, 'Don't move. I've got a blaster here. We'll just wait for the scientists to get here one by one. One by one we'll X-ray them. One by one, we'll monitor them for radioactivity. No two will get together without being checked, and if all five hundred are clear, I'll give you my blaster and surrender to you. Only I think we'll find the ten humanoids. Sit down, Breckenridge.'

  They both sat.

  Lynn said, 'We wait. When I'm tired, Laszlo will spell me. We wait.'

  Professor Manuelo Jiminez of the Institute of Higher Studies of Buenos Aires exploded while the stratospheric jet on which he traveled was three miles above the Amazon Valley. It was a simple chemical explosion but it was enough to destroy the plane.

  Dr. Herman Liebowitz of M.I.T. exploded in a monorail, killing twenty people and injuring a hundred others.

  In similar manner, Dr. Auguste Marin of L'Institut Nucleonique of Montreal and seven others died at various stages of their journey to Cheyenne.

  Laszlo hurtled in, pale-faced and stammering, with the first news of it. It had only been two hours that Lynn had sat there, facing Breckenridge, blaster in hand.

  Laszlo said, 'I thought you were nuts, Chief, but you were right. They were humanoids. They had to be.' He turned to stare with hate-filled eyes at Breckenridge. 'Only they were warned. He warned them, and now there won't be one left intact. Not one to study.'

  'God!' cried Lynn and in a frenzy of haste thrust his blaster out toward Breckenridge and fired. The Security man's neck vanished; the torso fell; the head dropped, thudded against the floor and rolled crookedly.

  Lynn moaned, 'I didn't understand, I thought he was a traitor. Nothing more.'

  And Laszlo stood immobile, mouth open, for the moment incapable of speech.

  Lynn said wildly, 'Sure, he warned them. But how could he do so while sitting in that chair unless he were equipped with built-in radio transmission? Don't you see it? Breckenridge had been in Moscow. The real Breckenridge is still there. Oh my God, there were eleven of them.'

  Laszlo managed a hoarse squeak. 'Why didn't he ex­plode?'

  'He was hanging on, I suppose, to make sure the others had received his message and were safely destroyed. Lord, Lord, when you brought the news and I realized the truth, I couldn't shoot fast enough. God knows by how few seconds I may have beaten him to it.'

  Laszlo said shakily, 'At least, we'll have one to study.' He bent and put his fingers on the sticky fluid trickling out of the mangled remains at the neck end of the headless body.

  Not blood, but high-grade machine oil.

  Part Three

  Susan Calvin

  The robot short stories that most interested me, however, were those that dealt with Dr. Susan Calvin, robopsychologist extraordinary. A 'robopsychologist' is not a robot who is a psychologist, but a psychologist who is also a roboticist. It is an ambiguous word, unfortunately, but 1 am stuck with it.

  As time went on, I fell in love with Dr. Calvin. She was a forbidding creature, to be sure—much more like the popular conception of a robot than were any of my positronic creations—but I loved her anyway.

  She served as the central bond that knit together the stories of I, Robot, and in four of the stories she played a central role. Whats more, after I, Robot appeared (and despite the fact that the book contained an epilog briefly noting Dr. Calvin's death at an advanced age) I couldn't help bringing her back. I wrote four more stories dealing with her.

  In one of these, dear Susan appeared only glancingly. This was 'Satisfaction Guaranteed,' which appeared in the April 1951 issue of Amazing Stories.

  An interesting point about this story is the unusual quantity of mail from readers, almost all young ladies, and almost all speaking wistfully of Tony—as though I might know where he could be found.

  I shall attempt to draw no morals (or immorals, either) from this.

  SATISFACTION GUARANTEED

  Tony was tall and darkly handsome, with an in­credibly patrician air drawn into every line of his un­changeable expression, and Claire Belmont regarded him through the crack in the door with a mixture of horror and dismay.

  'I can't, Larry. I just can't have him in the house.' Feverishly, she was searching her paralyzed mind for a stronger way of putting it; some way that would make sense and settle things, but she could only end with a simple repetition.

  'Well, I can't!'

  Larry Belmont regarded his wife stiffly, and there was that spark of impatience in his eyes that Claire hated to see, since she felt her own incompetence mirrored in it. 'We're committed. Claire,' he said, 'and I can't have you backing out now. The company is sending me to Washington on this basis, and it probably means a promotion. It's perfectly safe and you know it. What's your objection?'

  She frowned helplessly. 'It just gives me the chills. I couldn't bear him.'

  'He's as human as you or I, almost. So, no nonsense. Come, get out there.'

  His hand was in the small of her back, shoving; and she found herself in her own living room, shivering. It was there, looking at her with a precise politeness, as though appraising his hostess-to-be of the next three weeks. Dr. Susan Calvin was there, too, sitting stiffly in thin-lipped abstraction. She had the cold, faraway look of someone who has worked with machines so long that a little of the steel had entered the blood.

  'Hello,' crackled Claire in general, and ineffectual, greet­ing.

  But Larry was busily saving the situation with a spurious gaiety. 'Here, Claire, I want you to meet Tony, a swell guy. This is my wife, Claire, Tony, old boy.' Larry's hand draped itself amiably over Tony's shoulder, but Tony re­mained unresponsive and expressionless under the pressure.

  He said, 'How do you do, Mrs. Belmont.'

  And Claire jumped at Tony's voice. It was deep and mellow, smooth as the hair on his head or the skin on his face.

  Before she could stop herself, she said, 'Oh, my—you talk.'

  'Why not? Did you expect that I didn't?'

  But Claire could only smile weakly. She didn't really know what she had expected. She looked away, then let him slide gently into the corner of her eye. His hair was smooth and black, like polished plastic—or was it really composed of separate hairs? And was the even, olive skin of his hands and face continued on past the obscurement of his formally cut clothing?

  She was lost in the shuddering wonder of it, and had to force her thoughts back into place to meet Dr. Calvin's flat, unemotional voice.

  'Mrs. Belmont, I hope you appreciate the importance of this experiment. Your husband tells me he has given you some of the background. I would like to give you more, as the senior psychologist of the U.S. Robots and Mechanical Men Corporation.

  'Tony is a robot. His actual designation on the company files is TN-3, but he will answer to Tony. He is not a mechanical monster, nor simply a calculating machine of the type that were developed during World War II, fifty years ago. He has an artificial brain nearly as complicated as our own. It is an immense telephone switchboard on an atomic scale, so that billions of possible "telephone con­nections" can be compressed into an instrument that will fit inside a skull.

  'Such brains are manufactured for each model of robot spe
cifically. Each contains a precalculated set of connec­tions so that each robot knows the English language to start with and enough of anything else that may be necessary to perform his job.

  'Until now, U.S. Robots has confined its manufacturing activity to industrial models for use in places where human labor is impractical—in deep mines, for instance, or in underwater work. But we want to invade the city and the home. To do so, we must get the ordinary man and woman to accept these robots without fear. You understand that there is nothing to fear.'

  'There isn't, Claire,' interposed Larry earnestly. 'Take my word for it. It's impossible for him to do any harm. You know I wouldn't leave him with you otherwise.'

  Claire cast a quick, secret glance at Tony and lowered her voice. 'What if I make him angry?'

  'You needn't whisper,' said Dr. Calvin calmly. 'He can't get angry with you, my dear. I told you that the switch­board connections of his brain were predetermined. Well, the most important connection of all is what we call "The First Law of Robotics," and it is merely this: "A robot may not injure a human being, or, through inaction, allow a human being to come to harm." All robots are built so. No robot can be forced in any way to do harm to any human. So, you see, we need you and Tony as a preliminary experiment for our own guidance, while your husband is in Washington to arrange for government-supervised legal tests.'

  'You mean all this isn't legal?'

  Larry cleared his throat. 'Not just yet, but it's all right. He won't leave the house, and you mustn't let anyone see him. That's all... And, Claire, I'd stay with you, but I know too much about the robots. We must have a com­pletely inexperienced tester so that we can have severe conditions. It's necessary.'

  'Oh, well,' muttered Claire. Then, as a thought struck her, 'But what does he do?'

  'Housework,' said Dr. Calvin shortly.

  She got up to leave, and it was Larry who saw her to the front door. Claire stayed behind drearily. She caught a glimpse of herself in the mirror above the mantelpiece, and looked away hastily. She was very tired of her small, mousy face and her dim, unimaginative hair. Then she caught Tony's eyes upon her and almost smiled before she remem­bered... He was only a machine.

  Larry Belmont was on his way to the airport when he caught a glimpse of Gladys Claffern. She was the type of woman who seemed made to be seen in glimpses... Per­fectly and precisely manufactured; dressed with thoughtful hand and eye; too gleaming to be stared at.

  The little smile that preceded her and the faint scent that trailed her were a pair of beckoning fingers. Larry felt his stride break; he touched his hat, then hurried on.

  As always he felt that vague anger. If Claire could only push her way into the Claffern clique, it would help so much. But what was the use?

  Claire! The few times she had come face to face with Gladys, the little fool had been tongue-tied. He had no illusions. The testing of Tony was his big chance, and it was in Claire's hands. How much safer it would be in the hands of someone like Gladys Claffern.

  Claire woke the second morning to the sound of a sub­dued knock on the bedroom door. Her mind clamored, then went icy. She had avoided Tony the first day, smiling thinly when she met him and brushing past with a wordless sound of apology.

  'Is that you-—Tony?'

  'Yes, Mrs. Belmont. May I enter?'

  She must have said yes, because he was in the room, quite suddenly and noiselessly. Her eyes and nose were simultaneously aware of the tray he was carrying.

  'Breakfast?' she said.

  'If you please.'

  She wouldn't have dared to refuse, so she pushed herself slowly into a sitting position and received it: poached eggs, buttered toast, coffee.

  'I have brought the sugar and cream separately,' said Tony. 'I expect to learn your preference with time, in this and in other things.'

  She waited.

  Tony, standing there straight and pliant as a metal rule, asked, after a moment, 'Would you prefer to eat in privacy?'

  'Yes...I mean, if you don't mind.'

  'Will you need help later in dressing?'

  'Oh, my, no!' She clutched frantically at the sheet, so that the coffee hovered at the edge of catastrophe. She re­mained so, in rigor, then sank helplessly back against the pillow when the door closed him out of her sight again.

  She got through breakfast somehow... He was only a machine, and if it were only more visible that he were it wouldn't be so frightening. Or if his expression would change. It just stayed there, nailed on. You couldn't tel! what went on behind those dark eyes and that smooth, olive skin-stuff. The coffee cup beat a faint castanet for a mo­ment as she set it back, empty, on the tray.

  Then she realized that she had forgotten to add the sugar and cream after all, and she did so hate black coffee.

  She burned a straight path from bedroom to kitchen after dressing. It was her house, after all, and there wasn't any­thing frippy about her, but she liked her kitchen clean. He should have waited for supervision...

  But when she entered, she found a kitchen that might have been minted fire-new from the factory the moment before.

  She stopped, stared, turned on her heel and nearly ran into Tony. She yelped.

  'May I help?' he asked.

  'Tony,' and she scraped the anger off the edges of her mind's panic, 'you must make some noise when you walk. I can't have you stalking me, you know...Didn't you use this kitchen?'

  'I did, Mrs. Belmont.'

  'It doesn't look it.'

  'I cleaned up afterward. Isn't that customary?'

  Claire opened her eyes wide. After all, what could one say to that? She opened the oven compartment that held the pots, took a quick, unseeing look at the metallic glitter inside, then said with a tremor, 'Very good. Quite satis­factory.'

  If at the moment, he had beamed; if he had smiled; if he had quirked the corner of his mouth the slightest bit, she felt that she could have warmed to him. But he remained an English lord in repose, as he said, 'Thank you, Mrs. Belmont. Would you come into the living room?'

  She did, and it struck her at once. 'Have you been polish­ing the furniture?'

  'Is it satisfactory, Mrs. Belmont?'

  'But when? You didn't do it yesterday.'

  'Last night, of course.'

  'You burned the lights all night?'

  'Oh, no. That wouldn't have been necessary. I've a built-in ultra-violet source. I can see in ultraviolet. And, of course, I don't require sleep.'

  He did require admiration, though. She realized that, then. He had to know that he was pleasing her. But she couldn't bring herself to supply that pleasure for him.

  She could only say sourly, 'Your kind will put ordinary houseworkers out of business.'

  'There is work of much greater importance they can be put to in the world, once they are freed of drudgery. After all, Mrs. Belmont, things like myself can be manufactured. But nothing yet can imitate the creativity and versatility of a human brain, like yours.'

  And though his face gave no hint, his voice was warmly surcharged with awe and admiration, so that Claire flushed and muttered, 'My brain! You can have it.'

  Tony approached a little and said, 'You must be un­happy to say such a thing. Is there anything I can do?'

  For a moment, Claire felt like laughing. It was a ridicu­lous situation. Here was an animated carpet-sweeper, dish­washer, furniture-polisher, general factotum, rising from the factory table—and offering his services as consoler and confidant.

  Yet she said suddenly, in a burst of woe and voice, 'Mr. Belmont doesn't think I have a brain, if you must know... And I suppose I haven't.' She couldn't cry in front of him. She felt, for some reason, that she had the honor of the human race to support against this mere creation.

  'It's lately,' she added. 'It was all right when he was a student; when he was just starting. But I can't be a big man's wife; and he's getting to be a big man. He wants me to be a hostess and an entry into social life for him—like G—guh—guh—Gladys Claffern.'

>   Her nose was red, and she looked away.

  But Tony wasn't watching her. His eyes wandered about the room. 'I can help you run the house.'

  'But it's no good,' she said fiercely. 'It needs a touch I can't give it. I can only make it comfortable; I can't ever make it the kind they take pictures of for the Home Beauti­ful magazines.'

  'Do you want that kind?'

  'Does it do any good—wanting?'

  Tony's eyes were on her, full. 'I could help.'

  'Do you know anything about interior decoration?'

  'Is it something a good housekeeper should know?'

  'Oh, yes.'

  'Then I have the potentialities of learning it. Can you get me books on the subject?'

  Something started then.

  Claire, clutching her hat against the brawling liberties of the wind, had manipulated two fat volumes on the home arts back from the public library. She watched Tony as he opened one of them and nipped the pages. It was the first time she had watched his fingers flicker at anything like fine work.

  I don't see how they do it, she thought, and on a sudden impulse reached for his hand and pulled it toward herself. Tony did not resist, but let it lie limp for inspection.

  She said, 'It's remarkable. Even your fingernails look " natural.'

  'That's deliberate, of course,' said Tony. Then, chattily, 'The skin is a flexible plastic, and the skeletal framework is a light metal alloy. Does that amuse you?'

  'Oh, no.' She lifted her reddened face. 'I just feel a little embarrassed at sort of poking into your insides. It's none of my business. You don't ask me about mine.'

  'My brain paths don't include that type of curiosity. I can only act within my limitations, you know.'

  And Claire felt something tighten inside her in the silence that followed. Why did she keep forgetting he was a machine? Now the thing itself had to remind her. Was she so starved for sympathy that she would even accept a robot as equal—because he sympathized?

  She noticed Tony was still flipping the pages—almost helplessly—and there was a quick, shooting sense of re­lieved superiority within her. 'You can't read, can you?'

  Tony looked up at her; his voice calm, unreproachful. 'I am reading, Mrs. Belmont.'