How did Newtons approach to understanding planetary motions differ from that of his prodecessors?
Newton created a mathematics that could actually predict Kepler’s law based on a central 1/r^2 force (gravity). This mathematics is known today as Calculus. All other mathematical relationships regarding planetary motions prior to this time were only empirical (Kepler foudn an equation that fit the observations.) Newton was able to derive these relationships starting from a relatively simple set of assumptions. Kepler know about the p^2 proportional to a^3 relationship but could not have explained why. Newton was able to say that using a central force that falls off as 1/r^2 and the understanding of the relationship between force and acceleration and acceleration and velocity, planets will orbit the sun according to Kepler’s empirical law.
