The Meaning of 'Ought': Beyond Descriptivism and Expressivism in Metaethics

The word ‘ought’ is one of the core normative terms, but it is also a modal word. This book develops a careful account of the semantics of ‘ought’ as a modal operator and uses this to motivate a novel inferentialist account of why ought-sentences have the meaning that they have. Traditionally, theories that treat normative statements as descriptions of how reality might be have claimed the advantage of continuity with truth-conditional approaches to semantics; and theories that treat normative statements as expressions of nonbelief attitudes have claimed the advantage of explaining their distinctive evaluative and motivational character. The inferentialist theory defended in this book agrees with descriptivist theories in metaethics that specifying the truth conditions of normative sentences is a central part of the explanation of their meaning. However, it is argued (based on the comparison to semantics for modal operators) that this doesn’t settle the question of whether ought-statements describe reality. Moreover, the inferentialist theory defended in this book also agrees with expressivist theories that normative statements have special evaluative potentials. However, it is argued that the standard Humean model of this kind of evaluation in terms of statements expressing desire-like pressures on action is too narrow. Accordingly, the traditional debate leaves unanswered important metasemantic questions about what it is in virtue of which ought-sentences have the meanings they have. The sort of inferentialism about ‘ought’ developed in this book is meant to provide a viable antidescriptivist but also antiexpressivist answer to these questions.