Elements of the Philosophy of Newton (French: Éléments de la philosophie de 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.^[1]

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."^[2]

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.^[3]

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 indivisible Atoms, and that the simple Particles of Light are Atoms of that kind. Discoveries continued.

Chapter XI

Of the Rainbow; that Phenomenon a necessary Effect of the Laws of Refrangibility.

Chapter XII

New Discoveries touching the Cause of Colours, which confirm the preceding Doctrine; Demonstration that Colours are occasioned by the Density and Thickness of the Parts of which Bodies are composed (or the Thickness of the Parts that compose the Surfaces only).

Chapter XIII

Consequences of these Discoveries. The mutual Action of Bodies upon Light.

Chapter XIV

Of the Resemblance between the seven Primitive Colours and the seven Notes in Musick.

Chapter XV

Introductory Ideas concerning Gravity and the Laws of Attraction: That the Opinion of a subtil Matter, Vortices, and a Plenitude, ought to be rejected (But not that subtile Aether which Sir Isaac makes the Cause of Attraction, Refraction, Animal Motion, &c. which pervades the Universe).

Chapter XVI

That the Vortices and Plenitude of Descartes are impossible, and consequently that there is some other Cause of Gravity.

Chapter XVII

What is meant by Vacuity and Space, without which there could be neither Gravity nor Motion.

Chapter XVIII

Gravitation demonstrated from the Discoveries of Galileo and Newton: That the Moon revolves in her Orbit by the Force of this Gravitation.

Chapter XIX

That Gravitation and Attraction direct all the Planets in their Courses.

Chapter XX

Demonstrations of the Laws of Gravitation, drawn from the Rules of Kepler: That one of these Laws of Kepler demonstrates the Motion of the Earth.

Chapter XXI

New Proofs of Attraction. That the Inequalities of the Motion and Orbit of the Moon are necessarily the Effects of Attraction.

Chapter XXII

New Proofs and New Effects of Gravitation. That this Power is in every Particle of Matter. Discoveries dependent on this Principle.

Chapter XXIII

The Theory of our Planetary World.

Chapter XXIV

Of the Zodiacal Light, the Comets, and the fixed Stars.

Chapter XXV

Of the second Inequalities of the Motion of the Satellites, and the Phaenomena that depend thereon.

Glossary

Explanations of the hard Words used in this Treatise.

•  French Wikisource has original text related to this article: Eléments de la philosophie de Newton (1745)