Philosophy 2203E Lecture Notes - Lecture 12: Centripetal Force, General Scholium, Foundationalism
3 Oct 2016
School
Department
Course
Professor
Document Summary
The history of astronomical investigation teaches us that the inference from experience to hypotheses is a subtle business. Centripetal motion would become unmanageable in a cartesian universe. In the principia, newton explains the motions of bodies, both terrestrial & extraterrestrial, in terms of gravity he acknowledges that gravity is a front to reasoning it"s a mystery. However, the principia does not assign a cause to gravity. It acts in boyle"s vacuum" act over empty space. It acts not in proportion to the quantity of the surfaces of the particles on which it acts (as mechanical causes are wont to do) but in proportion to the quantity of solid matter - I have not as yet been able to deduce from phenomena the reason for these properties of gravity & i do not feign hypotheses" (newton) Kepler"s 3rd law: the cubes of the distances of the planets are proportional to the squares of their periodic times.
