Political discussion is often considered essential for a healthy democracy, but what motivates people to engage in it? Traditionally, objective political knowledge—holding factually correct beliefs about politics—has been considered a crucial prerequisite for political action, such as political talk. Recent research challenges this conventional wisdom, arguing that subjective knowledge—individuals’ metacognitive perceptions of their own knowledge—may be a more accurate predictor of political engagement more broadly. Thus, in this study, we sought to better understand how both objective and subjective political knowledge relate to political discussion with different audiences (in-group, out-group, strong ties, and weak ties). Results from a 2-wave survey (YouGov) of U.S. adults (W1 = 1,800; W2 = 1,265) showed that people who think they know a lot about politics are more willing to engage in all types of political discussion. In contrast, objective knowledge is only associated with political discussions with political in-group members and strong ties. Thus, discussions with the out-group members and weak ties may be motivated by a flawed perception of knowledge that is not supported by actual facts and information (i.e., knowledge illusion).
