The book is made up of six meditations, in which Descartes first discards all belief in things which are not absolutely certain, and then tries to establish what can be known for sure. The meditations were written as if he was meditating for 6 days: each meditation refers to the last one as "yesterday". However, Descartes did not take 6 days to complete this work, it actually took several years.
Ren? Descartes, known as the Father of Modern Philosophy and inventor of Cartesian coordinates, was a seventeenth century French philosopher, mathematician, and writer. Descartes made significant contributions to the fields of philosophy and mathematics, and was a proponent of rationalism, believing strongly in fact and deductive reasoning. Working in both French and Latin, he wrote many mathematical and philosophical works including The World, Discourse on a Method, Meditations on First Philosophy, and Passions of the Soul. He is perhaps best known for originating the statement I think, therefore I am.