To evaluate whether something is likely to be true, people attend to whether it is compatible with other things they know, internally consistent and plausible, supported by evidence, accepted by others, and offered by a credible source. Each criterion can be evaluated by drawing on relevant details (an effortful analytic strategy) or by attending to the ease with which the claim can be processed (a less effortful intuitive strategy). Easy processing favors acceptance under all criteria, even when more careful processing would identify the claim as faulty. Intuitive assessments of truth have important implications for the role of social media and the correction of false claims. Social media are characterized by high message repetition, selective filtering and sharing, and easy-to-process formats, all of which foster acceptance of a claim as true. Popular correction strategies typically confront false claims with facts. This works while the facts are still highly accessible, but backfires after a delay because extensive thought about false claims during the correction phase increases fluent processing when the claim is re-encountered later. At that point, the facts are less accessible and fluent processing of the now familiar false claim can facilitate its acceptance.