 Descartes repeatedly says we mistakenly suppose the things represented by ideas of SQs resemble the ideas. Is it possible for ideas to represent things and yet be misleading about what they are? The issue comes to a head in remarks about “materially false” ideas in Mediation 3. This is a non-judgmental sort of falsity “that occurs in ideas when they represent non-things as things”; for instance, ideas of heat and cold do not enable us to know whether one is the privation of the other, both are privative, or both are positive. Because there cannot be an idea that is not intentional, or of something, the idea that represents it as something positive should be called false (CSM 2.30; AT.7, 43–44). Arnauld objects that on Descartes’ theory, X cannot exist objectively in the mind as something other than it is; were the idea of X materially false, it would not be an idea of X (CSM 2.145–46; AT 7.206–07). Three points in Descartes’ reply are reasonably clear. First, material falsity does not have to do with the relation between an idea and its object but with the mental operation that makes the object appear in a manner that does not enable us to tell whether its object is privative or positive (CSM 2.162–3; AT 7.232). Second, ideas of SQs are confused and obscure; they involve sensations which are often wrongly taken to be the objects the ideas represent. Third, Descartes agrees with Arnauld: the idea of cold, e.g., cannot represent cold as something it is not (CSM 2.164; AT 7.234; for a different interpretation, see M. Wilson 1978: 114–16). The upshot is that ideas of color etc. are confused. They provide opportunity for error but are not erroneous representations (Hatfield 2011: 143–148). Scholars disagree about how to interpret these texts in an internally consistent way. There are two basic positions: