Cartesian

Of or relating to the philosophy or methods of Descartes.

[French cartésien (from René DESCARTES) and New Latin Cartesiānus (from Cartesius, Latin form of Descartes).]

Adjective derived from the Latin name of René Descartes: Renatus Cartesius.

adj.

Relating to Descartes, a famous philosopher, author of the celebrated dictum, Cogito ergo sum -- whereby he was pleased to suppose he demonstrated the reality of human existence. The dictum might be improved, however, thus: Cogito cogito ergo cogito sum -- "I think that I think, therefore I think that I am;" as close an approach to certainty as any philosopher has yet made.

The adjective has one meaning:

Meaning #1: of or relating to Rene Descartes or his works
  Pertains to noun: Descartes (meaning #1)