died Feb. 11, 1650, Stockholm, Sweden
Rene Descartes invented the famous Cartesian coordinate system.He worked in the field of analytic geometry.
Rene desscartes was the father of mathematics.
== == Oddly enough, the place now called Descartes. Initially called La Haye en Touraine, the town was renamed La Haye-Descartes in 1802 in his honour, and then renamed again to Descartes in 1967.
Short answer: Descartes' doubt was like WWI - the doubt to end all doubt. Only by doubting everything could Descartes hope to find anything that was certain (even if the only certainty is that nothing else is certain!).
Some math mathematicians say that Descartes inspiration came from being in bed so late. But, this also came about because of his love for math and all of his studying.
Ren Renfa died in 1327.
Cao Ren died in 223.
Ren Yaxiang died in 662.
Ren Bishi died in 1950.
Ren Guang died in 1941.
Hong Ren died in 1664.
Ren Xun died in 1893.