Rene Descartes (31 March 1596 – 11 February 1650) was a French philosopher, mathematician and writer. Descartes is renowned for being the so called "Father of Modern Philosophy". Descartes was a rationalist. In his evil demon argument he attempted to skepticism against its supporters by assuming that he was being deceived then disregarded everything and began thinking from scratch with what could not be doubted.
- I think, therefore I exist.