How (not) to argue about is/ought inferences in the cognitive sciences

When scholars problematize is/ought inferences (IOI's), they sometimes refer to Hume's or Moore's fallacy (e.g., Schneider, 2000; Schroyens, 2009; Elqayam and Evans, 2011). Although inferring "ought" from "is" can be problematic, we argue that, in the context of contemporary IOI's in the cognitive sciences, invoking Hume or Moore might be misguided. This is because Hume's and Moore's arguments concern the validity and soundness of deductive inferences while in our view contemporary IOI's in the cognitive sciences are better interpreted as defeasible inferences.