Descartes´ Secret Notebook : A True Tale of Mathematics, Mysticis

Rene Descartes (1596-1650) is one of the towering and central figures in Western philosophy and mathematics. His apothegm ""Cogito, ergo sum"" marked the birth of the mind-body problem, while his creation of so-called Cartesian coordinates have made our physical and intellectual conquest of physical space possible. But Descartes had a mysterious and mystical side, as well. Almost certainly a member of the occult brotherhood of the Rosicrucians, he kept a secret notebook, now lost, most of which was written in code. After Descartes´s death, Gottfried Leibniz, inventor of calculus and one of the greatest mathematicians in history, moved to Paris in search of this notebook--and eventually found it in the possession of Claude Clerselier, a friend of Descartes. Leibniz called on Clerselier and was allowed to copy only a couple of pages--which, though written in code, he amazingly deciphered there on the spot. Leibniz´s hastily scribbled notes are all we have today of Descartes´s notebook, which has disappeared. Why did Descartes keep a secret notebook, and what were its contents? The answers to these questions lead Amir Aczel and the reader on an exciting, swashbuckling journey, and offer a fascinating look at one of the great figures of Western culture.