robotic unit that would be based on a hugely powerful positronic brain, fully imbued with the Three Laws. It would, in effect, be a robot mind without a robot body.
There had been a tremendous controversy over whether to trust the fate of the planet to a mindless machine, or to a robotic brain that would refuse to take necessary risks. It was easy to imagine a robotic control unit choosing to avoid harm to one human, rather than permit a project vital to the future of the planet. The robotics experts all promised that it didn't work that way, but experts had been wrong before. Governor Grieg had died before he could reveal his choice between the two systems. In one of the first acts of his administration, Kresh had decided to build both, and interconnect them so that the two systems worked in consensus with each other. In theory, if the two systems could not reach agreement on what to do, or not to do, they were to call in human referees to decide the issue. In practice, the two systems had agreed with each other far more often than anyone could have hoped. Thus far, there had only been a half dozen or so very minor issues that had required human decisions.
A vast planetary network of sensors and probes, orbiting satellites, mobile units, and on-site investigators, both robotic and human, fed a constant stream of information to both units-and both units fed back a constant stream of instructions and commands to the humans and robots and automatic machines in the field.
The two interconnected control centers were the only devices on the planet capable of handling the constant stream of incoming data and outgoing instructions. It was plainly obvious that the two of them would have to be consulted regarding the plan to drop a comet on the planet, but Kresh did not wish to risk the sanity of the robotic unit. "You saw what just happened to Donald," he said. "Will I burn the Robotic Center out if I ask it what I should do?"
Fredda smiled reassuringly. "There wouldn't be much point in having a Robotic Control Center that couldn't consider risks to the planet without damaging itself," she said. "It took some doing, but we installed some special...safeguards, shall we say, that should keep it from experiencing any serious First Law conflict."
"Good, good," said Kresh, a bit absently. "At least that's one less thing to worry about. At least we know that part is all right."
"Do we?" Fredda asked. "I wonder. When Lentrall asked me about Donald's name, and how it was not from Shakespeare, that made me wonder."
"Wonder what?"
"I was absolutely certain it was from Shakespeare. No doubt at all in my mind. I never bothered to double-check, any more than I would have bothered to double-check the spelling of my own name. I thought I knew it-and I was dead wrong."
"We all make mistakes," Kresh said.
"Yes, yes, of course," Fredda said, impatiently. "But that's not the point. In a sense, it's a trivial mistake. But it came out of a trusted database. Who knows how long ago the dataset got scrambled, or what else in it is wrong? And if that database can be wrong, lots of other things can be as well. What else is there that we think we know? What other hard fact that we think we have absolutely right will turn out to be absolutely dead wrong? What else do we think we know?"
There was a moment of long and uncomfortable silence.
But uncertainty surrounded all of life. To wait until one was sure was to remain frozen in place until it was too late. "We'll never be able to answer that question," said Kresh. He paused for a moment and thought. "You're thinking like a scientist," he said. "And up until now, I've been thinking like a politician. Maybe it's time to think like a police officer."
"I must admit that I do not see how the police viewpoint would be of much use in this situation," said Fredda.
"Because back when I was a policeman, I knew I didn't know," said Kresh. "I knew, on every case, that some knowledge was hidden, and that I would never have absolutely complete or totally accurate information. But I still had to act. I still had to decide. I had to take the facts I had-or thought I had-and ride them as far as they would take me." He stepped around Donald so he was