I examine the role that Descartes's theory of optics plays in Cartesian methodology. After explaining the importance of methodology in Descartes's project, I outline his method in terms of the three dimensions of time. I put this method to work by describing Descartes's search for the elusive hyperbolic lens, a lens that would offer the type of perfect vision that is necessary for the Cartesian scientific process. It soon becomes clear that this lens is the mind itself. The task of this project is thus to sculpt the mind so as to achieve the highest clarity and distinctness of scientific vision. Thus, by focusing on how the eye works and how seeing can be improved, the subject and the objects it sees both radically transform in structure, content, and kind. The Cartesian corpus thus initiates a sort of specular regime that produces a new subjectivity and a new world.