At last, Quinn turned to Calvin, "You've said nothing. Tell me what you think. "Now, Susan Lanning warned. "Let her talk," Quinn said smoothly. Susan Calvin fixed cold eyes on Quinn. There are only two ways to prove Byerley is a robot. You can X-ray him. or you can study his psychology, lf he has a positronic brain, then he must obey the Three Laws of Robotics. Do you know them?" Quinn nodded. "If Byerley breaks any of those laws, then he isn't a robot. If he follows all the laws, he may be a robot, or he may simply be a very good man. "So you're telling me that you can never prove him a robot?" 1 may be able to prove that he isn't a robot. The politician stood up. Then we shall see what Mr Byerley's body looks like under his skin. Somehow, I'm going to get evidence that he's a robot.' And he left the Lanning turned impatiently to Calvin. "Why do you insist on "I won't lie for you,' she replied sharply. And what happens to US Robots if he opens up Byerley and a lot of wheels and electrical bits and pieces fall out? What then? He won't open up Byerley,' said Calvin confidently. "Byerley is at least as clever as Quinn. The newspapers were full of reports about the robot
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