 In “Eclaircissement XI,” Malebranche attempts to counter “the authority of Descartes” by arguing that the Cartesians themselves must admit that they have only a confused awareness of the nature of the sensory modifications of the soul. He notes that while the intellectual idea allows the various modes of extension to be related in a precise manner, there is no clear scale on which we can order our sensations of different shades of the same color, not to mention our sensations of sensible qualities of different kinds. Malebranche takes the confusion in the sensations to reveal a confusion in our perception of the nature of the soul. He adds that Cartesians can discern that sensible qualities are modifications of an immaterial soul only by seeing that they are “not clearly contained in the idea we have of matter.” For a discussion sympathetic to Malebranche’s critique of Descartes’s account of our knowledge of mind, see Schmaltz (1996); for more recent discussions that defend Descartes against this critique, see Nolan and Whipple (2005) and LoLorodo (2005).