Excerpts from Books and Wikipedia
"Isaac Newton's theory of gravitation 'completes' the Copernican revolution, establishing the preeminence of science in the Western world." [Lyons: House of Wisdom, p. xiv] Philosophiæ Naturalis Principia Mathematica (Latin for Mathematical Principles of Natural Philosophy), often referred to as simply the Principia (...), is a work in three books by Isaac Newton, in Latin, first published 5 July 1687. . . . The Principia states Newton's laws of motion, forming the foundation of classical mechanics; Newton's law of universal gravitation; and a derivation of Kepler's laws of planetary motion (which Kepler first obtained empirically)." [Wikipedia]