Paul 'Scruffy' Martin talks of Sir Isaac Newton FRS (25th December 1642 - 20th March 1727) who was an English physicist, mathematician, astronomer, natural philosopher, alchemist, and theologian, and is considered by many scholars and members of the general public to be one of the most influential people in human history. His Philosophiæ Naturalis Principia Mathematica (Latin for "Mathematical Principles of Natural Philosophy"; usually called the Principia), published in 1687, is probably the most important scientific book ever written. It lays the groundwork for most of classical mechanics. In this work, Newton showed that the motions of objects on Earth and of celestial bodies are governed by the same set of natural laws, by demonstrating the consistency between Kepler's laws of planetary motion and his theory of gravitation; thus removing the last doubts about heliocentrism and advancing the Scientific Revolution.