The publisher's special commentary chapter and the author's biography are included in this version. Philosophiae Naturalis Principia Mathematica by Sir Isaac Newton is often referred to as the Principia. The book introduces Sir Isaac Newton's mathematical principles of natural philosophy and his system of the world. The name of the book is Latin for “Mathematical Principles of Natural”. It was first published in July 1687 and the following two editions were published in 1713 and 1726. The Principia states Newton's laws of motion, forming the foundation of classical mechanics, also Newton's law of universal gravitation, and a derivation of Kepler's laws of planetary motion (which Kepler first obtained empirically).