In Alan Gewirth's The Cartesian Circle Reconsidered, he expands on an argument made in a previous article regarding a possible logical fallacy in Descartes' Meditations on Early Philosophy. This fallacy is called the Cartesian Circle in reference to Descartes' seemingly circular reasoning that he may have clear and distinct ideas because of the existence of God, but that the proof of God's existence is itself based on clear and distinct ideas. Gewirth's response to Descartes' critics is that Descartes uses different types of certainty to demonstrate the existence and truth of God versus the accuracy of clear and distinct ideas. The latter of these types of certainty, metaphysical certainty, is what he focuses on in The Cartesian Circle Reconsidered. Gewirth details three interpretations of why simple propositions are susceptible to metaphysical doubt: operational, conceptual, and ontological. His thesis is that Descartes intends only ontological doubt in the Meditations. However, while his arguments for and against the conceptual interpretation are strong, his claim that the operational interpretation is weak is not as reasonable. The operational interpretation holds that the potential doubt of simple propositions arises in part from a deception in the functioning of memory about previous intuitions and not just the intuitions themselves. Descartes himself says something along these lines in the third meditation: "When I consider the nature of the triangle, it appears to me very clearly... that its three angles are equal to two right angles, and I cannot help believing that this is true as long as I attend to the proof; but as soon as I turn my mental gaze elsewhere, even if I remember having perceived it clearly, I can easily dou...... middle of paper ...... legitimate. While Gewirth brings clear arguments to favor and contrary to other interpretations, his argument against the operational interpretation is neither clear nor supported in the text as strongly as the others. Descartes specifically describes doubt about both intuitions and the memories that follow from them, and these are not necessarily as mutually exclusive as Gewirth would have his reader believe. Works Cited DESCARTES, René. "Descartes' Meditations and Associated Texts." Second ed. Indianapolis: Hackett, 2009. 35-68. Kindle AZW File.GEWIRTH, Alan. “The Cartesian circle reconsidered”. The Journal of Philosophy 67:19 (1970): 668-685. Philosophers' Index, EBSCOhost (accessed January 27, 2014). http://flagship.luc.edu/login?url=http://search.ebscohost.com/login.aspx?direct=true&db=phl&AN=PHL1030595&site=ehost-live