According to the 2-system account of Theory of Mind proposed by Apperly and Butterfill (2009), reasoning about other people’s beliefs is slow and effortful (as opposed to reasoning about others’ perceptual registrations, which is automatic). While this account might explain the results of false-belief tasks with infants and children, we argue that it does not account for the epistemic inferences that we derive in everyday conversation. We report two self-paced reading experiments showing that adults reason about others’ beliefs fast and efficiently in passing conversation with strangers and acquaintances, challenging Apperly and Butterfill’s 2-system account of Theory of Mind.