Kepler's laws of planetary motion planets. However, Newton states in his Principia that he considers forces from a mathematical point of view, not a physical, thereby taking an instrumentalist view. Moreover, he does not assign a cause to gravity. Newton defined the force acting on a planet to be the product of its mass and the acceleration (see Newton's laws of motion). So: The Sun plays an unsymmetrical part, which is unjustified. So he assumed, in Newton's law of universal gravitation: As the planets have small masses compared to that of the Sun, the orbits conform approximately to Kepler's laws. Newton's model improves upon Kepler's
Three Laws of Robotics Three Laws. However, the 1960s German TV series "Raumpatrouille – Die phantastischen Abenteuer des Raumschiffes Orion" ("Space Patrol – the Fantastic Adventures of Space Ship Orion") bases episode three titled ""Hüter des Gesetzes"" ("Guardians of the Law") on Asimov's Three Laws without mentioning the source. References to the Three Laws have appeared in popular music ("Robot" from Hawkwind's 1979 album "PXR5"), cinema ("Repo Man", "Aliens", ""), cartoon series ("The Simpsons"), tabletop roleplaying games (Paranoia) and webcomics ("Piled Higher and Deeper" and "Freefall"). Robby the Robot in "Forbidden Planet" (1956) has a hierarchical command structure which keeps him from harming humans,