“Hold on,” broke in Bogert angrily. “That’s not necessarily true. You want to hear that, that’s all.”

“Don’t be a fool,” replied Calvin. “He certainly knows as much math as you and Lanning together, since he can read minds. Give him his chance.”

The mathematician subsided, and Calvin continued, “All right, then, Herbie, give! We’re waiting.” And in an aside, “Get pencils and paper, gentlemen.”

But Herbie remained silent, and there was triumph in the psychologist’s voice, “Why don’t you answer, Herbie?”

The robot blurted out suddenly, “I cannot. You know I cannot. Dr. Bogert and Dr. Lanning don’t want me to.”

“They want the solution.”

“But not from me.”

Lanning broke in, speaking slowly and distinctly, “Don’t be foolish, Herbie. We do want you to tell us.”

Bogert nodded curtly.

Herbie’s voice rose to wild heights, “What’s the use of saying that? Don’t you suppose that I can see past the superficial skin of your mind? Down below, you don’t want me to. I’m a machine, given the imitation of life only by virtue of the positronic interplay in my brain—which is man’s device. You can’t lose face to me without being hurt. That is deep in your mind and won’t be erased. I can’t give the solution.”

“We’ll leave,” said Dr. Lanning. “Tell Calvin.”

“That would make no difference,” cried Herbie, “since you would know anyway that it was I that was supplying the answer.”

Calvin resumed, “But you understand, Herbie, that despite that, Drs. Lanning and Bogert want that solution.”

“By their own efforts!” insisted Herbie.

“But they want it, and the fact that you have it and won’t give it hurts them. You see that, don’t you?”

“Yes! Yes!”

“And if you tell them that will hurt them, too.”

“Yes! Yes!” Herbie was retreating slowly, and step by step Susan Calvin advanced. The two men watched in frozen bewilderment.

“You can’t tell them,” droned the psychologist slowly, “because that would hurt and you mustn’t hurt. But if you don’t tell them, you hurt, so you must tell them. And if you do, you will hurt and you mustn’t, so you can’t tell them; but if you don’t, you hurt, so you must; but if you do, you hurt, so you mustn’t; but if you don’t, you hurt, so you must; but if you do, you—”

Herbie was up against the wall, and here he dropped to his knees. “Stop!” he shrieked. “Close your mind! It is full of pain and frustration and hate! I didn’t mean it, I tell you! I tried to help! I told you what you wanted to hear. I had to!”

The psychologist paid no attention. “You must tell them, but if you do, you hurt, so you mustn’t; but if you don’t, you hurt, so you must; but—”

And Herbie screamed!

It was like the whistling of a piccolo many times magnified—shrill and shriller till it keened with the terror of a lost soul and filled the room with the piercingness of itself.