Foucault illustrates his point through a striking discussion of Descartes’ cogito, showing why it is an indubitable certitude within the classical episteme, but not within the modern episteme. There are two ways of questioning the force of the cogito. One is to suggest that the subject (the thinking self, the I) that Descartes concludes necessarily exists in the act of thinking is something more than just the act of representing objects; so we cannot go from representation to a thinker. But for