Three Laws of Robotics authorities such as doctors, teachers and so forth which equals the Second Law of Robotics. Finally humans are typically expected to avoid harming themselves which is the Third Law for a robot. The plot of "Evidence" revolves around the question of telling a human being apart from a robot constructed to appear human – Calvin reasons that if such an individual obeys the Three Laws he may be a robot or simply "a very good man". Another character then asks Calvin if robots are very different from human beings after all. She replies, "Worlds different. Robots are essentially decent." Asimov
Three Laws of Robotics telepaths with extended brains and specialized organs) The Laws of Robotics presume that the terms "human being" and "robot" are understood and well defined. In some stories this presumption is overturned. The Solarians create robots with the Three Laws but with a warped meaning of "human". Solarian robots are told that only people speaking with a Solarian accent are human. This enables their robots to have no ethical dilemma in harming non-Solarian human beings (and they are specifically programmed to do so). By the time period of "Foundation and Earth" it is revealed that the Solarians have genetically modified themselves