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
Clarke's three laws same time. Clarke's first law was proposed in the 1962 edition of the essay, as "Clarke's Law" in "Profiles of the Future". The second law is offered as a simple observation in the same essay but its status as Clarke's second law was conferred by others. It was initially a derivative of the first law and formally became Clarke's second law where the author proposed the third law in the 1973 revision of "Profiles of the Future," which included an acknowledgement"." It was also here that Clarke wrote about the third law in these words: "As three laws were good