Certainty the fact that he was one of the first to write on the topic and acted as a comparison for the traditional and definitive works of the Western tradition. Descartes' "Meditations on First Philosophy" is a book 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. Although the phrase "Cogito, ergo sum" is often attributed to Descartes' "Meditations on First Philosophy", it is actually put forward in his "Discourse on Method". Due to the implications of inferring the conclusion within the predicate, however, he
Cogito, ergo sum distinctiveness of self-evident propositions — to establish true and justified propositions despite having adopted a method of generalized doubt. As a consequence of this demonstration, Descartes considers science and mathematics to be justified to the extent that their proposals are established on a similarly immediate clarity, distinctiveness, and self-evidence that presents itself to the mind. The originality of Descartes's thinking, therefore, is not so much in expressing the "cogito" — a feat accomplished by other predecessors, as we shall see — but on using the "cogito" as demonstrating the most fundamental epistemological principle, that science and mathematics are justified by