Descartes, René

(rn´ dkärt´) (KEY), Lat. Renatus Cartesius, 1596–1650, French philosopher, mathematician, and scientist,

b. La Haye. Descartes’ methodology was a major influence in the transition from medieval science and philosophy to the modern era.

1 Life Descartes was educated in the Jesuit College at La Flèche and the Univ. of Poitiers, then entered the army of Prince Maurice of Nassau. In 1628 he retired to Holland, where he spent his time in scientific research and philosophic reflection. Even before going to Holland, Descartes had begun his great work, for the essay on algebra and the Compendium musicae probably antedate 1628. But it was with the appearance in 1637 of a group of essays that he first made a name for himself. These writings included the famous Discourse on Method and other essays on optics, meteors, and analytical geometry. In 1649 he was invited by Queen Christina to Sweden, but he was unable to endure the rigors of the northern climate and died not long after arriving in Sweden.

2 Elements of Cartesian Philosophy It was with the intention of extending mathematical method to all fields of human knowledge that Descartes developed his methodology, the cardinal aspect of his philosophy. He discards the authoritarian system of the scholastics and begins with universal doubt. But there is one thing that cannot be doubted: doubt itself. This is the kernel expressed in his famous phrase, Cogito, ergo sum [I think, therefore I am].

3 From the certainty of the existence of a thinking being, Descartes passed to the existence of God, for which he offered one proof based on St. Anselm’s ontological proof and another based on the first cause that must have produced the idea of God in the thinker. Having thus arrived at the existence of God, he reaches the reality of the physical world through God, who would not deceive the thinking mind by perceptions that are illusions. Therefore, the external world, which we perceive, must exist. He thus falls back on the acceptance of what we perceive clearly and distinctly as being true, and he studies the material world to perceive connections. He views the physical world as mechanistic and entirely divorced from the mind, the only connection between the two being by intervention of God. This is almost complete dualism.

4 The development of Descartes’ philosophy is in Meditationes de prima philosophia (1641); his Principia philosophiae (1644) is also very important. His influence on philosophy was immense, and was widely felt in law and theology also. Frequently he has been called the father of modern philosophy, but his importance has been challenged in recent years with the demonstration of his great debt to the scholastics. He influenced the rationalists, and Baruch Spinoza also reflects Descartes’s doctrines in some degree. The more direct followers of Descartes, the Cartesian philosophers, devoted themselves chiefly to the problem of the relation of body and soul, of matter and mind. From this came the doctrine of occasionalism, developed by Nicolas Malebranche and Arnold Geulincx.

5 Major Contributions to Science In science, Descartes discarded tradition and to an extent supported the same method as Francis Bacon, but with emphasis on rationalization and logic rather than upon experiences. In physical theory his doctrines were formulated as a compromise between his devotion to Roman Catholicism and his commitment to the scientific method, which met opposition in the church officials of the day. Mathematics was his greatest interest; building upon the work of others, he originated the Cartesian coordinates and Cartesian curves; he is often said to be the founder of analytical geometry. To algebra he contributed the treatment of negative roots and the convention of exponent notation. He made numerous advances in optics, such as his study of the reflection and refraction of light. He wrote a text on physiology, and he also worked in psychology; he contended that emotion was finally physiological at base and argued that the control of the physical expression of emotion would control the emotions themselves. His chief work on psychology is in his Traité des passions de l’âme (1649).

6 Bibliography See J. Maritain, The Dream of Descartes (tr. 1944, repr. 1969); J. R. Vrooman, René Descartes (1970); A. G. Balz, Descartes and the Modern Mind (1952, repr. 1967); H. Caton, The Origin of Subjectivity: An Essay on Descartes (1973).

 

Cartesian coordinate

Function: noun Date: circa 1888 1 : either of two coordinates that locate a point on a plane and measure its distance from either of two intersecting straight-line axes along a line parallel to the other axis 2 : any of three coordinates that locate a point in space and measure its distance from any of three intersecting coordinate planes measured parallel to that one of three straight-line axes that is the intersection of the other two planes

http://www.geom.umn.edu/docs/reference/CRC-formulas/node38.html

 

Non-Cartesian Cognitive Science

Traditional Cognitive Science is Cartesian in the sense that it takes as fundamental the distinction between the mental and the physical, the mind and the world, the subject and the object. It is this Cartesianism which leads to such claims as that cognition must be representational and that what sets cognizers apart is the fact that they exhibit "aboutness".

 

dualism, Cartesian interactionist - The view that: (1) the mental and the material comprise two different classes of substance and; (2) both can have causal effects on the other. See dualism.

skepticism, Cartesian

skepticism, Cartesian - Any of a class of skeptical views against empirical knowledge based on the claim that claims to empirical knowledge are defeated by the possibility that we might be deceived insofar as we might be, for example, dreaming, hallucinating, deceived by demons, or brains in vats. The gist of Cartesian-style skeptical arguments is that some empirical proposition (e.g. that there are trees) cannot be known because we might be deceived (e.g. we might be brains in vats hallucinating that there are trees). Related forms of these arguments attack our justification for believing some empirical proposition on grounds of possible deception. These 'justification' versions undermine claims to knowledge insofar as justification is a necessary condition on knowledge. The arguments I examine below are all of the 'knowledge' variety, but they can easily be transformed into arguments of the 'justification' variety by simply replacing all occurrences of 'knowledge' with 'justification'.

Here is a simple Cartesian-style skeptical argument:

A. I know that there are trees only if I know that I am not deceived that there are trees.

B. I do not know that I am not deceived that there are trees.

C. Therefore, I do not know that there are trees.