Elements of the Philosophy of Newton () is a book written by the philosopher Voltaire and co-authored by mathematician and physicist Émilie du Châtelet in 1738 that helped to popularize the theories and thought of Isaac Newton. This book, coupled with Letters on the English, written in 1733, demonstrated that Voltaire had moved beyond the simple poetry and plays he had written previously. A new edition was published in 1745 that contained an initial section on Newton's metaphysics, originally published separately in 1740. By 1745, when the edition of Voltaire's Éléments was published, the tides of thought were turning his way, and by 1750 the perception had become widespread that France had been converted from erroneous Cartesianism to modern Newtonianism thanks to Voltaire. Charles Coulston Gillispie says that "Voltaire explained Newtonian science to the educated public more successfully than any other writer, perhaps because he took more pains to understand it." Contents Chapter I What Light is, and in What manner it comes to us. Chapter II The Property, which Light has of reflecting itself, was not truly known. It is not reflected by the solid Parts of Bodies as vulgarly believed. Chapter III Of the property which Light has of refracting in passing from one Substance into another, and of taking a new Course in its Progression. Chapter IV Of the Form of the Eye, and in what manner Light enters and acts in that Organ. Chapter V Of Looking–Glasses, and Telescopes: Reasons given by Mathematicians for the Mysteries of Vision; that those Reasons are not altogether sufficient. Chapter VI In what Manner we know Distances, Magnitudes, Figures, and Situations. Chapter VII Of the Cause of the breaking of the Rays of Light in passing from one Medium to another; that this Cause is a general Law of Nature unknown before Newton; that the Inflection of Light is also an Effect of the same Cause. Voltaire discusses a case wherein Dr. William Cheselden healed the sight of a blind teenage boy. Voltaire notes that upon seeing for the first time, the boy thought the images were resting on his eyeballs. Chapter VIII The wonderful Effects of the Refraction of Light. The several Rays of Light have all possible Colours in themselves; what Refrangibility is. New Discoveries. Chapter IX The Cause of Refrangibility; from which it appears that there are indivisible Bodies in Nature. Chapter X Proof that there are