Discourse on the Method and Meditations on First Philosophy

DISCOURSE ON THE METHOD AND MEDITATIONS ON FIRST PHILOSOPHY TOGETHER IN ONE VOLUME
Discourse on the Method is a philosophical and autobiographical treatise published by René Descartes in 1637. Discourse on the Method is one of the most influential works in the history of modern philosophy, and important to the development of natural sciences.
Meditations on First Philosophy is a philosophical treatise by René Descartes first published in 1641. The book is made up of six meditations, in which Descartes first discards all belief in things that are not absolutely certain, and then tries to establish what can be known for sure. He wrote the meditations as if he had meditated for six days: each meditation refers to the last one as yesterday. (In fact, Descartes began work on the Meditations in 1639.)
One of the most influential philosophical texts ever written, it is widely read to this day.