  The RNB view of Arcesilaus denies that his acceptance of inapprehensibility and universal suspension is explained in terms of belief in the premises and hence in the conclusions of his arguments. Rather, on this account Arcesilaus guides his rational activity by something like a supposition or hypothesis—a set of notions deployed variously in Plato’s dialogues, Theophrastus’ dialectic, and geometrical theory (see Schofield 1999 and Thorsrud 2018; cf. Bénatouïl &amp; El Murr 2010). Even the Stoics distinguished hypotheticals from assertions and arguments, such that one can accept hypotheses and what follows from them without asserting them (see Barnes 1997). Arcesilaus could have adapted this kind of theory to account for the rational activities of the skeptic. Accounts of impression and assent also afford a distinction between beliefs and belief-like imaginings such as suppositions, which may then take the place of beliefs in chains of inference. This distinction allows for a reasoned commitment that falls short of assent (see Striker 1980, Bett 1990, and Reinhardt 2018). Arcesilaus, on this view, supposes that we ought to live without realist commitments that fix our view of the world. His supposition may have been based on premises—some of which he shared with Zeno—as well as on a generalization from his philosophical experience, after repeatedly finding that rational inquiry does not justify assent.