“Listen, Greg,” Donovan grew desperately urgent. “I’ve got an idea. That robot may be lying. He never—”

“Robots can’t knowingly lie, you fool. Now if we had the McCormack-Wesley tester, we could check each individual item in his body within twenty-four to forty-eight hours, but the only two M.-W. testers existing are on Earth, and they weigh ten tons, are on concrete foundations and can’t be moved. Isn’t that peachy?”

Donovan pounded the desk, “But, Greg, he only goes wrong when we’re not around. There’s something—sinister—about—that.” He punctuated the sentence with slams of fist against desk.

“You,” said Powell, slowly, “make me sick. You’ve been reading adventure novels.”

“What I want to know,” shouted Donovan, “is what we’re going to do about it.”

“I’ll tell you. I’m going to install a visiplate right over my desk. Right on the wall over there, see!” He jabbed a vicious finger at the spot. “Then I’m going to focus it at whatever part of the mine is being worked, and I’m going to watch. That’s all.”

“That’s all? Greg—”

Powell rose from his chair and leaned his balled fists on the desk, “Mike, I’m having a hard time.” His voice was weary. “For a week, you’ve been plaguing me about Dave. You say he’s gone wrong. Do you know how he’s gone wrong? No! Do you know what shape this wrongness takes? No! Do you know what brings it on? No! Do you know what snaps him out? No! Do you know anything about it? No! Do I know anything about it? No! So what do you want me to do?”

Donovan’s arm swept outward in a vague, grandiose gesture, “You got me!”

“So I tell you again. Before we do anything toward a cure, we’ve got to find out what the disease is in the first place. The first step in cooking rabbit stew is catching the rabbit. Well, we’ve got to catch that rabbit! Now get out of here.”

Donovan stared at the preliminary outline of his field report with weary eyes. For one thing, he was tired and for another, what was there to report while things were unsettled? He felt resentful.

He said, “Greg, we’re almost a thousand tons behind schedule.”

“You,” replied Powell, never looking up, “are telling me something I don’t know.”

“What I want to know,” said Donovan, in sudden savagery, “is why we’re always tangled up with new-type robots. I’ve finally decided that the robots that were good enough for my great-uncle on my mother’s side are good enough for me. I’m for what’s tried and true. The test of time is what counts—good, solid, old-fashioned robots that never go wrong.”

Powell threw a book with perfect aim, and Donovan went tumbling off his seat.

“Your job,” said Powell, evenly, “for the last five years has been to test new robots under actual working conditions for United States Robots. Because you and I have been so injudicious as to display proficiency at the task, we’ve been rewarded with the dirtiest jobs. That,” he jabbed holes in the air with his finger in Donovan’s direction, “is your work. You’ve been griping about it, from personal memory, since about five minutes after United States Robots signed you up. Why don’t you resign?”