 It might seem Meditations offers such an argument. It states that our most common mistake about ideas in general consists in judging that they resemble things outside us (CSM 2.26; AT 7.37). Some scholars take this to be an attack on Aristotelian realism, but the argument is elusive. The problem is that the context indicates that assuming resemblance is an epistemic mistake but not necessarily a factual one (e.g., CSM 2.57; AT 7.82–3). That is, making the assumption is assenting to something we have no reason to think is true; but it may nevertheless be true. Perceptual realism about SQs tacitly goes by the board, but the opponent in view is the epistemic stance of those who formed the habit of implicitly relying on their senses as children and never reflected on its value for acquiring true beliefs. (For this interpretation of Descartes’ method of doubt, see Patterson 2007.)