"René Descartes (/deɪˈkɑːrt/ or UK: /ˈdeɪkɑːrt/; French: [ʁəne dekaʁt]; Latinized: Renatus Cartesius; 31 March 1596 – 11 February 1650) was a French philosopher, mathematician, and scientist who invented analytic geometry, linking the previously separate fields of geometry and algebra. He spent a large portion of his working life in the Dutch Republic, initially serving the Dutch States Army of Maurice of Nassau, Prince of Orange and the Stadtholder of the United Provinces. One of the most notable intellectual figures of the Dutch Golden Age, Descartes is also widely regarded as one of the founders of modern philosophy and algebraic geometry.
Many elements of Descartes's philosophy have precedents in late Aristotelianism, the revived Stoicism of the 16th century, or in earlier philosophers like Augustine. In his natural philosophy, he differed from the schools on two major points: first, he rejected the splitting of corporeal substance into matter and form; second, he rejected any appeal to final ends, divine or natural, in explaining natural phenomena. In his theology, he insists on the absolute freedom of God's act of creation. Refusing to accept the authority of previous philosophers, Descartes frequently set his views apart from the philosophers who preceded him. In the opening section of the Passions of the Soul, an early modern treatise on emotions, Descartes goes so far as to assert that he will write on this topic "as if no one had written on these matters before." His best known philosophical statement is "cogito, ergo sum" ("I think, therefore I am"; French: Je pense, donc je suis), found in Discourse on the Method (1637; in French and Latin) and Principles of Philosophy (1644, in Latin).
Descartes has often been called the father of modern philosophy, and is largely seen as responsible for the increased attention given to epistemology in the 17th century. He laid the foundation for 17th-century continental rationalism, later advocated by Spinoza and Leibniz, and was later opposed by the empiricist school of thought consisting of Hobbes, Locke, Berkeley, and Hume. In the 17th-century Dutch Republic, the rise of early modern rationalism – as a highly systematic school of philosophy in its own right for the first time in history – exerted an immense and profound influence on modern Western thought in general, with the birth of two influential rationalistic philosophical systems of Descartes (who spent most of his adult life and wrote all his major work in the United Provinces of the Netherlands) and Spinoza – namely Cartesianism and Spinozism. It was the 17th-century arch-rationalists like Descartes, Spinoza and Leibniz who have given the "Age of Reason" its name and place in history. Leibniz, Spinoza, and Descartes were all well-versed in mathematics as well as philosophy, and Descartes and Leibniz contributed greatly to science as well.
Descartes's Meditations on First Philosophy (1641) continues to be a standard text at most university philosophy departments. Descartes's influence in mathematics is equally apparent; the Cartesian coordinate system was named after him. He is credited as the father of analytic geometry, the bridge between algebra and geometry—used in the discovery of infinitesimal calculus and analysis. Descartes was also one of the key figures in the Scientific Revolution."
(from Wikipedia)
"Discourse on the Method of Rightly Conducting One's Reason and of Seeking Truth in the Sciences (French: Discours de la Méthode Pour bien conduire sa raison, et chercher la vérité dans les sciences) is a philosophical and autobiographical treatise published by René Descartes in 1637. It is best known as the source of the famous quotation "Je pense, donc je suis" ("I think, therefore I am", or "I am thinking, therefore I exist"), which occurs in Part IV of the work. A similar argument, without this precise wording, is found in Meditations on First Philosophy (1641), and a Latin version of the same statement Cogito, ergo sum is found in Principles of Philosophy (1644).
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. In this work, Descartes tackles the problem of skepticism, which had previously been studied by other philosophers. While addressing some of his predecessors and contemporaries, Descartes modified their approach to account for a truth he found to be incontrovertible; he started his line of reasoning by doubting everything, so as to assess the world from a fresh perspective, clear of any preconceived notions.
The book was originally published in Leiden, in the Netherlands. Later, it was translated into Latin and published in 1656 in Amsterdam. The book was intended as an introduction to three works: Dioptrique, Météores and Géométrie. La Géométrie contains Descartes's initial concepts that later developed into the Cartesian coordinate system. The text was written and published in French rather than Latin, the latter being the language in which most philosophical and scientific texts were written and published at that time. Most of Descartes' other works were written in Latin.
Together with Meditations on First Philosophy, Principles of Philosophy and Rules for the Direction of the Mind, it forms the base of the epistemology known as Cartesianism."
(from Wikipedia)
Discourse on the Method of Rightly Conducting the Reason, and Seeking Truth in the Sciences