For 10 points, name this author of Discourse on Method, a Frenchman who invented a coordinate graphing system and said "I think, therefore I am."
This believer in a human faculty called the "natural light" made an error of reasoning in accepting what he called "clear and distinct" truths; that error is his namesake "circle." He wrote in letters to Princess Elizabeth of Bohemia that the "seat of the soul" might be the pineal gland. This tutor to Princess Christina of Sweden proposed that a malicious demon might be altering all his sensory input, and argued that the mind interacts non-materially with the body, starting off his namesake "dualism." For 10 points, name this author of Discourse on Method, a Frenchman who invented a coordinate graphing system and said "I think, therefore I am."
This believer in a human faculty called the "natural light" made an error of reasoning in accepting what he called "clear and distinct" truths; that error is his namesake "circle."
Rene Descartes [or Renatus Cartesius] &lt;MJ&gt;