Verbal irony characteristically involves the expression of a derogatory, dissociative attitude. The ironic speaker is not only stating a blatant falsehood or irrelevant proposition; she is also communicating her stance towards its epistemic status. The centrality of attitude expression and recognition in verbal irony makes it very different from other figurative and non-literal uses of language. This difference is well reflected by experimental data showing that the acquisition, comprehension and processing of irony come with additional demands: irony understanding is acquired later in development, it is often impaired in clinical populations and is effortful from a processing perspective. This opens up the question of which cognitive abilities make it possible.
Drawing on Wilson (2009), we argue that epistemic vigilance plays a crucial role in recognizing the speaker’s ironical intent and inferring her attitude. To do so, we introduce the distinction between first- and second-order epistemic vigilance: while the former assesses the credibility of the incoming information and the reliability of the individuals who dispense it, the latter evaluates others’ epistemic vigilance towards the content and the source of the information. We argue that first- and second-order vigilance both play a role in irony understanding. We thus examine their distinctive contributions to detect contextual incongruency, distinguish verbal irony from lies or mistakes, as well as recognize the dissociative stance conveyed by the ironic speaker.