Moral language and Moore's Paradox: Challenging moral expressivism

Moore's Paradox-e.g., "It's raining but I don't think it's raining"-is widely considered infelicitous despite being logically consistent. In this paper, we extend Moore's Paradox to moral discourse and test whether moral statements like "Murder is wrong but I don't disapprove of it" elicit similar intuitions. Rooted in moral expressivism, the Parity Thesis predicts that moral assertions express non-cognitive attitudes (e.g., approval/disapproval) in a manner analogous to how descriptive statements express beliefs. In a pre-registered study with 1200 participants, we empirically test this thesis using a mixed design that manipulates moral term type (thick vs thin), evaluative polarity (positive vs negative), perspective (first vs third person), and attitude (belief vs disapproval). The results of our main study and one qualitative follow-up study suggest that while moral statements resemble Moorean Paradoxes in important ways, participants find it largely acceptable to call an action wrong without disapproving of it. As the infelicity of such statements is a core ingredient of Moorean Paradoxes and, as we suggest, the Parity Thesis, we conclude that moral language does not express approval and disapproval like declarative language expresses beliefs.