Although often remembered best for the quotation "I think, therefore I am," the philosopher and mathematician, Rene Descartes, also developed the Cartesian coordinate system, made significant contributions to the field of optics and devised a mechanistic model of physics. In addition to being considered the father of modern philosophy, based primarily on his breaking away from the previously adhered-to Scholastic-Aristotelian tradition, Descartes is also viewed as one of the major figures in the scientific revolution that was taking place in the 17th century. One of his most ambitious undertakings was the development of a systematic theory of deduction and knowledge based on methodological skepticism that eventually grew into 17th-century European rationalism.
Distrustful of reasoning based on sensory perceptions, which he believed could be deceptive, Descartes set out to determine a basic premise that would prove to be fully resistant to all forms of doubt. His famous statement "I think, therefore I am" was the result of this search, and it laid the foundation for a line of reasoning based on deduction and causal explanations existing within a mechanistic framework.
The mathematical system developed by Descartes and named after him, the Cartesian coordinate system, proved extremely influential by serving as a bridge between geometry and algebra. It paved the way for the later developments of calculus and mathematical analysis. Descartes' system provided an innovative means by which equations could be expressed geometrically in a two-dimensional plane based on their coordinates within the graphical field of x- and y-axes he designed.