The elements of Newton's philosophy. By Voltaire. (Guildford and London: Billing and Sons Ltd., 1967. Pp xvi, 363.) In this essay, published in 1738, Voltaire explains the philosophies not only of Newton, but also largely of Descartes because of his contributions in the areas of geometry. In his concise explanation of the paradigms of Newton and other philosophers related to the fields of astronomy and physics, Voltaire uses geometry through diagrams and images and proves his claims through calculation. Voltaire in fact mentions that this essay is aimed at those who have the desire to learn for themselves, and makes the intention of the book a manual. In 25 chapters, and each of 357 pages, as well as six pages of definitions, Voltaire explains Newton's discoveries in the field of optics, the spectrum and colors of the rainbow, musical notes, of the laws of attraction, refuting Descartes' philosophy of gravity and the structure of light, and proving Newton's new paradigm, or philosophy as Voltaire would have called it. In a way, Voltaire created the idea that Newton's principles constituted a new philosophy and recognized the possibility of errors. Through mathematical problems and solutions, Voltaire breaks the paradigm of any faithful observer of Descartes' philosophy and calls his way of thinking "Chaos" (Pp. 8). What amazed me was their ability to calculate things they were never able to do before, like the speed of light, proving that it only takes eight minutes for one or more rays of light from the Sun to reach the Earth. Through Newton's achievements in calculus and his use of geometry, Voltaire showed how we could estimate the distance between Earth and the stars and planets. Voltaire accurately calculates the time it takes the Sun to rotate as 25 and a half days, which is an accepted answer today due to the variance shifting towards the poles. This book was sometimes difficult to understand when reading calculus, but with the inclusion of geometry the material becomes accessible to more educated readers. Because it resembles a textbook intended to spread understanding of the new philosophy, this book should be recommended to anyone studying the history of science, philosophy, or any of the various influential philosophers who have contributed to the understanding and to truth through experimentation. the similarities between the English published in the late 1730s and that of today amazed me. The only real differences are some capitalizations that we don't follow, the use of a modified-looking lowercase f, which is pronounced with the s sound, and some European spelling..