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.

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