Why truth matters

Abstract This article is about truth and relevance. It first discusses the concept of truth in formal semantics and pragmatics, mainly the Gricean, neo-Gricean and post-Gricean approaches to meaning. What is particularly crucial is the relationship between pragmatic meaning and truth, since, from a Gricean perspective, meaning is defined as non-truth-conditional, which in turn raises the question of how truth can be a pragmatic issue. A second issue is the relationship between truth and relevance, as developed in relevance theory. A third key point is how truth matters as regards the common ground. In order to illustrate how truth is connected to the common ground, bullshit, post-truth, fake news and lies are discussed, which raise the issue of how truth can be defeated in verbal communication, and mainly how false assumptions can be entertained as true.