The father of modern western philosophy, René Descartes formulated the first modern version of mind-body dualism, promoting the development of a new science grounded in observation and experiment. Applying an original system of methodical doubt, he dismissed apparent knowledge derived from the senses and reason, establishing a new epistemic foundation on the basis of intuition, expressed in the dictum: "I think, therefore I am" (Cogito, ergo sum). This comprehensive eBook presents Descartes' collected works.