The Fourth Law of Robotics
by Harry Harrison
The secretary surged to her feet as I rushed by her desk.
“Stop! You can’t go in there! This is Dr. Calvin’s office!”
“I know,” I demurred. “That’s why I am here.”
Then I was through the door and it closed behind me. Dr. Calvin looked up and frowned at me through her reading glasses.
“You seem in quite a hurry, young man.”
“I am, Dr. Calvin, I am—” My words ground to a halt like an old Victrola with a busted spring. With her glasses off Dr. Calvin’s eyes were limpid pools of unfulfilled desire. Her figure, despite the lab gown, could not be disguised in its pulchritude.
“Did you look at my great-aunt in that steamy-eyed way, Dr. Donovan?” She smiled.
“No, no, of course not!” I stammered, rubbing my hand across my iron-gray hair. Or rather my bald skull fringed by iron-gray hair. And realized my mistake. “I was not looking at you in any particular way, Dr. Calvin.” She smiled warmly at that and an ache passed through every fiber of my being. I grabbed my mind by the neck and shook it, remembering my pressing errand. “I have a pressing errand, which is why I have burst into your office like this. I have reason to believe that a robot has just held up a bank.”
Well, as you might very well imagine, that got her attention. She dropped back into her chair, her eyes opened wide, she gasped, and I could see the sweat spring to her brow and the slight tremor of her hand.
“I can guess that you are a little surprised by this news,” I said.
“Not at all,” she sussurated. “It had to happen one day. Tell me about it. “
“I will do better—I will show you.”
I slipped the security camera ‘s visivox recording into the projector on her desk and thumbed it to life. One end of her office appeared to vanish, to be replaced by the interior of a financial establishment. Tellers dispensed money and services to attendant customers.
“I don’t see any holdup,” she said sweetly.
“Wait,” I cozened. Then the revolving door revolved and a man came into the bank. He was dressed in black from head to toe—black raincoat, black fedora hat, even black gloves and dark glasses. Even more interesting was the fact that when he turned to face the hidden camera, it could be seen that his features were concealed by a black ski mask. I saw that I had all of Dr. Calvin’s attention now.
We watched as he walked to the nearest free window. The teller looked up and smiled.
“May I help you?” he asked, the smile fading as he looked at the sinister figure before him.
“You may,” the man said in a woman’s clear contralto voice as he took a hand grenade from his pocket and held it out. Then pulled the pin and let the pin drop to the floor. “This is a hand grenade,” the lovely voice said.
“And I have pulled and discarded the pin. If I open my hand now the lever will fly off. Three seconds after release a hand grenade will explode. This kind of explosion tends to have a deleterious effect on people. Now I, for one, do not want this to happen and—I am just guessing?—I feel that you don’t want this to happen, either. Would you like to keep my hand closed? Just nod. That’s fine. Then we agree. Now I’ll bet that you think it is a really hunky-dory idea to take all of the money from your cash drawer, place it in this bag, and pass it back to me. How nice—you do think that it is a good idea. Very good! You have a nice day, hear.”
With this parting jest the man turned and strode across the bank. He was almost at the exit when the teller shouted a warning and alarm bells sounded.
What happened next was terrible. Unbelievable. Yet it happened. The thief turned and dropped the hand grenade, turned back and sprang at the revolving door, and pushed his way clear in the brief time before the grenade exploded.
“Close your eyes if you don’t want to watch,” I said.
“I can watch,” Dr. Calvin said grimly.
There was a burst of smoke from the grenade—and it emitted a shrill scream and a cloud of sparkling stars as it spun about. Then the shriek died away into silence, the fireworks stopped.
“It did not explode,” she observed.
“Quite correct.”
“And why do you assume that the thief was a robot? Because the figure appeared to be male yet he spoke with a female voice?”
“That was my first clue. Robot voice simulators are so perfect these days that to the casual ear they are perfect. Only computer analysis can pinpoint the artificial signal generation. So a robot can speak with a soprano or a bass voice.”
“And this one dressed as a man and used a woman’s voice. But why? To cause confusion?”
“Perhaps. Or perhaps—just as a joke.”
Dr. Calvin’s eyes widened and a trace of a smile touched her lips and was gone. “That is an intriguing thought, Dr. Donovan. Do go on. “
“This was my first clue as to the thief’s identity. But I needed more evidence. I found it—here. “
I touched the controls of the visivox and the action slowed. The masked figure turned to the revolving door, pushed and exited. The action repeated over and over.
“This is the vital clue. I had the revolving door removed and had it weighed. The entire unit weighs two hundred and thirty kilos. I then had the computer estimate the force needed to get it to reach this speed in this time for varying amounts of pressure. Watch the green computer trace now. This is the maximum pressure that can be exerted by a fifty-kilo woman working her hardest.”
The green trace appeared in the air—ending well behind the image of the moving door.
“Interesting,” Dr. Calvin observed. “Voice or not, that was not a woman. “
“Exactly. Now the blue trace you see coming up would be that of a seventy-five-kilo man. Next the orange trace of a hundred-kilo man of exceptional strength. “
This trace, like all of the others, ended well behind the image of the moving door, being pushed around by the hand of the bank robber. I actuated the controls again and a red trace appeared that swung out fat ahead of the others and ended at the moving door.
“The red trace,” she said. “Tell me about it.”
“That trace represents the amount of energy needed to accelerate that door from a zero-motion state to the speed it reached to permit the thief to exit with the money in the time observed. I can give you the foot-pounds or meter-kilograms if you wish—”
“Just roughly. How much energy?”
“Enough to lift that desk—and you as well—one meter into the air. “
“I thought so. As strong as an hydraulic ram. And well beyond the abilities of a human being.”
“But well within the abilities of a robot.”
“Point taken—and proven, Dr. Donovan. So what do you suggest that we do next?”
“Firstly—I suggest that we do not inform the police.”
“Withholding information from the authorities is a crime.”
“Not necessarily. So far we have only assumptions and no real evidence. We could take this guesswork to the police if that is your decision. Then we must consider the fact that we are making public information that might be considered derogatory toward the public image of U.S. Robots and Mechanical Men, Inc., information that would affect the price of its stocks, affect our bonuses and retirement plans—”
“There is no need to go on. We will keep this development quiet for the moment. Now what do we do next?”
“That’s a good question. Since all robots manufactured by us are leased and not sold, we could try to trace this one. “
Dr. Calvin’s eyebrows climbed skyward at this rash assumption.
“Isn’t that a rather rash assumption?” she asked. “Do you know how many robots we have manufactured—that are still functioning? And all of our production for the past two decades—except for special-function units—are roughly equivalent in bulk to a human being.”