Sir Isaac Newton's Philosophiae Naturalis Principia Mathematica

Sir Isaac Newton's "Philosophiæ Naturalis Principia Mathematica," commonly known as the Principia, is a foundational work in physics and astronomy. It formulates the laws of motion, explaining how objects move and interact, and introduces the law of universal gravitation, which states that every mass attracts every other mass with a force proportional to their masses and inversely proportional to the square of the distance between them. These principles unify celestial and terrestrial phenomena, allowing us to predict planetary movements, tides, and falling objects with remarkable precision, and laid the groundwork for classical mechanics.