Cartesian doubt is a form of methodological skepticism or scepticism associated with the writings and methodology of René Descartes (1596-1650). Cartesian doubt is also known as Cartesian skepticism, methodic doubt, methodological skepticism, Universal Doubt, or hyperbolic doubt. Methodological skepticism is distinguished from philosophical skepticism in that methodological skepticism is an approach that subjects all knowledge claims to scrutiny with the goal of sorting out true from false claims, whereas philosophical skepticism is an approach that questions the possibility of pure knowledge.