Philosophiæ Naturalis Principia Mathematica - Simple English Wikipedia, the free encyclopedia
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The Philosophiæ Naturalis Principia Mathematica (English: Mathematical Principles of Natural Philosophy) is a trilogy, written by Isaac Newton and published on 5 July 1687.
The three-book work describes physics and mathematics. It states Newton's laws of motion and the derivation of Kepler's Laws, and observations on gravity.