Sir Isaac Newton PRS MP (25 December 1642 - 20 March 1727) was an English physicist and mathematician who is widely regarded as one of the most influential scientists of all time and as a key figure in the scientific revolution. His book Philosophi Naturalis Principia Mathematica('Mathematical Principles of Natural Philosophy'), first published in 1687, laid the foundations for most of classical mechanics. Newton also made seminal contributions to optics and shares credit with Gottfried Leibni