René
Descartes was one of the most important philosophers and mathematicians of
the modern era. In Discourse on Method and The Meditations, he
reasoned that all of his prior knowledge was subject to doubt because it was
based on traditional beliefs rather than in rational, empirical thought. He
pondered what he could honestly say he knew to be true, going so far as to
doubt whether he was awake or dreaming—or if he even existed. He then began
to reconstruct his world view: he knew that his thoughts existed, which then
suggested the existence of a thinking being—himself. Descartes then came to
his famous conclusion, “Cogito ergo sum,”which means “I think, therefore, I am.”
