  This result is indicated by Descartes’s use of the term, picked up and emphasized by Malebranche, according to which there are no false ideas; every idea in this sense is materially true in that it has an object, and that is the object it appears to have. This conception of an idea is the basis for Descartes of what has been called the transparency of mind: I cannot be mistaken that I am thinking about what I am thinking about. Malebranche (whose entire philosophy was colored by his struggles with Descartes’s theory of ideas), in fact, later erected such incorrigible intentionality into the fundamental principle of his epistemology. Meanwhile, Descartes’s view that material or formal reality and objective reality are only rationally distinct might be taken to mean that minds are intrinsically intentional. A mind just is the sort of thing whose states are about something else. Arnauld extended this thesis, which adumbrates later thinkers such as Brentano, to include all mental phenomena, even sensations.