Should I say that? An experimental investigation into the norm of assertion

Assertions are our standard communicative devices for sharing and acquiring information. Recent studies seemingly provide converging evidence that assertions are subject to a factive norm: you are entitled to make an assertion only if it is true. However, these studies assume that we can treat participants’ judgements about what an agent ‘should say’ as evidence of their intuitions about assertability. This paper argues that this assumption is incorrect, so the conclusions drawn in these studies are unwarranted. We provide evidence that most people do not interpret statements about what one ‘should say’ as statements about assertability, but rather as statements about what is in the agent’s interest to do. Measures for prompting the intended reading of statements about what an agent ‘should say’ are identified, and their efficacy is tested. It is found that when these measures are implemented, people’s judgements consistently and overwhelmingly align with non-factive accounts of assertion.