"Dr. Susan Calvin: Detective, the room was security locked. Nobody came or went. You saw that yourself. Doesn't this have to be suicide? Detective Del Spooner: Yep. [drawing his gun] Unless the killer is still in here. [Spooner searches through the robot part as Calvin follows behind] Dr. Susan Calvin: You're joking, right? This is ridiculous. Detective Del Spooner: Yeah, I know. The Three Laws. Your perfect circle of protection. Dr. Susan Calvin: "A robot cannot harm a human being." The First Law of Robotics. Detective Del Spooner: Yeah, I've seen your commercials. But doesn't the Second Law say that a robot must obey any order given by a human. What if it was given an order to kill? Dr. Susan Calvin: Impossible! It would conflict with the First Law. Detective Del Spooner: Right, but the Third Law says that a robot can defend itself. Dr. Susan Calvin: Yes, but only if that action does not conflict with the First or Second Law. Detective Del Spooner: Well, you know what they say. Laws are made to be broken. Dr. Susan Calvin: No. Not these Laws. They are hard-wired into every robot. A robot can no more commit murder than a human can...walk on water."