The "Discourse on the Method" is a philosophical and mathematical essay published by René Descartes in 1637. This work is best known as the source of the famous quotation "Je pense, donc je suis" ("I think, therefore I am"). In addition, in one of its appendices, La Géométrie, is contained Descartes' first introduction of the Cartesian coordinate system, being the base of the Epistemology known as Cartesianism.
The “Discourse on the Method” is one of the most influential works in the history of modern science. It is a method which gives a solid platform from which all modern natural sciences could evolve. In this work, Descartes also tackles the problem of skepticism which had been revived from the ancients such as Sextus Empiricus by authors such as Al-Ghazali and Michel de Montaigne.