Cartesian coordinates are a way to find the location of a point using distances from perpendicular axes. (For more information about coordinates, see “Geometry and Trigonometry.”) The first steps toward such a coordinate system was suggested by French philosopher, mathematician, and scientist René Descartes (1596-1650; in Latin, Renatus Cartesius); he was the first to publish a work explaining how to use coordinates for finding points in space. Around the same time, Pierre de Fermat developed the same idea independently (see below). Both Descartes’s and Fermat’s ideas would lead to what is now known as Cartesian coordinates.

Descartes is also considered by some to be the founder of analytical geometry. He contributed to the ideas involved in negative roots and exponent notation, explained the phenomenon of rainbows and the formation of clouds, and even dabbled in psychology.