"Publicity works both ways, sir. If Quinn wants to call me a robot, and has the nerve to do so, I have the nerve to play the game his way."
"You mean you-" Lanning was quite frankly appalled.
"Exactly. I mean that I'm going to let him go ahead, choose his rope, test its strength, cut off the right length, tie the noose, insert his head and grin. I can do what little else is required."
"You are mighty confident."
Susan Calvin rose to her feet, "Come, Alfred, we won't change his mind for him."
"You see." Byerley smiled gently. "You're a human psychologist, too."
But perhaps not all the confidence that Dr. Lanning had remarked upon was present that evening when Byerley's car parked on the automatic treads leading to the sunken garage, and Byerley himself crossed the path to the front door of his house.
The figure in the wheel chair looked up as he entered and smiled. Byerley's face lit with affection. He crossed over to it.
The cripple's voice was a hoarse, grating whisper that came out of a mouth forever twisted to one side, leering out of a face that was half scar tissue, "You're late, Steve."
"I know, John, I know. But I've been up against a peculiar and interesting trouble today."
"So?" Neither the torn face nor the destroyed voice could carry expression but there was anxiety in the clear eyes. "Nothing you can't handle?"
"I'm not exactly certain. I may need your help. You're the brilliant one in the family. Do you want me to take you out into the garden? It's a beautiful evening."
Two strong arms lifted John from the wheel chair. Gently, almost caressingly, Byerley's arms went around the shoulders and under the swathed legs of the cripple. Carefully, and slowly, he walked through the rooms, down the gentle ramp that had been built with a wheel chair in mind, and out the back door into the walled and wired garden behind the house.
"Why don't you let me use the wheel chair, Steve? This is Silly."
"Because I'd rather carry you. Do you object? You know that you're as glad to get out of that motorized buggy for a while, as I am to see you out. How do you feel today?" He deposited John with infinite care upon the cool grass.
"How should I feel? But tell me about your troubles."
"Quinn's campaign will be based on the fact that he claims I'm a robot."
John's eyes opened wide, "How do you know? It's impossible. I won't believe it."
"Oh, come, I tell you it's so. He had one of the big-shot scientists of U. S. Robot amp; Mechanical Men Corporation over at the office to argue with me."
Slowly John's hands tore at the grass, "I see. I see."
Byerley said, "But we can let him choose his ground. I have an idea. Listen to me and tell me if we can do it-"
The scene as it appeared in Alfred Lanning's office that night was a tableau of stares. Francis Quinn stared meditatively at Alfred Lanning. Lanning's stare was savagely set upon Susan Calvin, who stared impassively in her turn at Quinn.
Francis Quinn broke it with a heavy attempt at lightness, "Bluff. He's making it up as he goes along."
"Are you going to gamble on that, Mr. Quinn?" asked Dr. Calvin, indifferently.
"Well, it's your gamble, really."
"Look here," Lanning covered definite pessimism with bluster, "we've done what you asked. We witnessed the man eat. It's ridiculous to presume him a robot."
"Do you think so?" Quinn shot toward Calvin. "Lanning said you were the expert."
Lanning was almost threatening, "Now, Susan-"
Quinn interrupted smoothly, "Why not let her talk, man? She's been sitting there imitating a gatepost for half an hour."
Lanning felt definitely harassed. From what he experienced then to incipient paranoia was but a step. He said, "Very well. Have your say, Susan. We won't interrupt you."
Susan Calvin glanced at him humorlessly, then fixed cold eyes on Mr. Quinn. "There are only two ways of definitely proving Byerley to be a robot, sir. So far you are presenting circumstantial evidence, with which you can accuse, but not prove - and I think Mr. Byerley is sufficiently clever to counter that sort of material. You probably think so yourself, or you wouldn't have come here.
"The two methods of proof are the physical and the psychological. Physically, you can dissect him or use an X-ray. How to do that would be your problem. Psychologically, his behavior can be studied, for if he is a positronic robot, he must conform to the three Rules of Robotics. A positronic brain cannot be constructed without them. You know the Rules, Mr. Quinn?"
She spoke them carefully, clearly, quoting word for word the famous bold print on page one of the "Handbook of Robotics."
"I've heard of them," said Quinn, carelessly.
"Then the matter is easy to follow," responded the psychologist, dryly. "If Mr. Byerley breaks any of those three rules, he is not a robot. Unfortunately, this procedure works in only one direction. If he lives up to the rules, it proves nothing one way or the other."
Quinn raised polite eyebrows, "Why not, doctor?"
"Because, if you stop to think of it, the three Rules of Robotics are the essential guiding principles of a good many of the world's ethical systems. Of course, every human being is supposed to have the instinct of self-preservation. That's Rule Three to a robot. Also every 'good' human being, with a social conscience and a sense of responsibility, is supposed to defer to proper authority; to listen to his doctor, his boss, his government, his psychiatrist, his fellow man; to obey laws, to follow rules, to conform to custom - even when they interfere with his comfort or his safety. That's Rule Two to a robot. Also, every 'good' human being is supposed to love others as himself, protect his fellow man, risk his life to save another. That's Rule One to a robot. To put it simply - if Byerley follows all the Rules of Robotics, he may be a robot, and may simply be a very good man."