Descartes' Doubt and Criterion of Turth

referring to Plato's Criticism of Relativism

Abstract

The purpose of this paper is to show that the main subject of Descartes' doubt in First Meditation is a reconsideration concerning 'Criterion of Truth' and 'Existence of Truth'. Having defined truth as something firm and lasting in advance, he begins to doubt his prejudices. This doubt is divided into three steps. First, having examined a dreaming state, he recognizes that there is no real thing independent of our thinking act (speech act), therefore he denies the correspondence theory. Second, suppose God deceives him, he thinks that we cannot believe in the permanence of logics and mathematics. In consequence, it turns out that the coherence theory cannot be an absolute criterion of truth. Third step, he hypothesizes a deceit by malign genius, and doubts his own belief that there is a firm and lasting truth.