Thus rendered, Descartes’ broader argument is viciously circular. The italicized segment of Arc 1 marks an addition to the original statement of it, thereby clarifying the circularity reading. Interpreted in this way, Descartes begins his Third Meditation proofs of God by presupposing the general veracity of clear and distinct perception. That is, he starts by assuming the C&D Rule and then uses the rule in the course of demonstrating it. Evidently, this way of reading Descartes’ argument ha