Philosophy Research Archives

Volume 13, 1987/1988

Kenneth R. Westphal
Pages 91-128

Sextus Empiricus Contra René Descartes

It has become a veritable industry to defend Descartes against the charge of circularity and, to a lesser extent, to argue that he successfully responds to the skepticism of Sextus Empiricus. Since one of Sextus’ main skeptical ploys is to press the charge of circularity against any view, and because Descartes does reply to Sextus, it is worthwhile to criticize these efforts in the same paper. I argue that Descartes did not successfully respond to Sextus’ skeptical arguments. I argue that he is guilty of not one but of five distinct circularities in his defense of empirical knowledge, thst clearing him of such charges can only be had by rendering him naively dogmatic, and that he fails to respond to a Pyrrhonisn contraposition argument. One circle concerns divine logical voluntarism. Another concerns the semantic component of innate ideas. A third arises from his natural inability to disbelieve whatever he clearly and distinctly perceives. A fourth circularity arises in Descartes’ proof that he cannot have generated his idea of God. A final circularity concerns Descartes’ attempt to verify the reliability of his thinking nature by employing that very same thinking nature. To substantiate these claims I review the principles of Sextus’ arguments briefly and I reexamine Descartes’ texts and doctrines in detail. I also take occasion to reflect on why Descartes’ foundationalist program must have failed.