2. Click on Change PC Settings.  Then click on Personalize in the left pane. 3. In the right pane, click on Lock screen and then Browse to find your desired image. When you find the image you want, highlight the file by clicking on it, and then click on Choose Picture in the lower right-hand corner.
Quick Answer. Rene Descartes, the French philosopher and mathematician who invented the Cartesian coordinate system, is considered the father of modern analytical geometry. His work was crucial to the discovery of infinitesimal calculus by Gottfried Liebniz and Isaac Newton. Continue Reading.
As he says in a letter to Guillaume Gibieuf (1583â1650), dated 19 January 1642, âI am certain that I can have no knowledge of what is outside me except by means of the ideas I have within me.â Descartes never published anything that specifically worked out a theory of ideas.