 Much ado has been made about whether dreaming arguments are self-refuting. According to an influential objection, similarity theses presuppose that we can reliably distinguish dreams and waking – we need first to distinguish them, in order to compare them; yet the conclusion of dreaming arguments entails that we cannot reliably distinguish. Therefore, if the conclusion of such an argument is true, then the premise invoking the Similarity Thesis cannot be. Some formulations of dreaming arguments are indeed self-refuting in this way. Of present interest is whether all are – specifically, whether Descartes makes the mistake. Interestingly, he does not. His formulation presupposes simply the truism that we do, in fact, make a distinction between dreaming and waking (never mind whether reliably). He states the relevant premise in terms of what we think of as dreams, versus what we think of as waking: “every sensory experience I have ever thought I was having while awake I can also think of myself as sometimes having while asleep” (AT 7:77, CSM 2:53, italics added). This formulation avoids the charge of self-refutation, for it is compatible with the conclusion that we cannot reliably distinguish dreams and waking.