July 5, 2025
On this day in 1687, Sir Isaac Newton published his key work titled Philosophiæ Naturalis Principia Mathematica. Commonly referred to as The Principia, this work is his original publication of the three fundamental Laws of Motion and the Law of Universal Gravitation that form the foundation of classical physics and celestial mechanics.
It is estimated that there could have been as many as 750 copies of the first edition of The Principia printed by the Royal Society, with potentially 400 copies surviving to present day. The Cambridge University Library houses Newton’s own copy of the first edition in its collections, complete with handwritten notes by Newton for the second edition, which was printed in 1713.
The image to the left is the cover of Philosophiæ Naturalis Principia Mathematica. The image on the right is a painting of Iaasc Newton from 1689 painted by the German painter Godfrey Kneller.
Images courtesy of Wikimedia Commons.
