Ethical theorists often assume that the verb ‘ought’ means roughly ‘has an obligation to’; however, this assumption is belied by the diversity of “flavors” of ought-sentences in English. A natural initial response is that ‘ought’ is multiply ambiguous between senses which have to do with obligations and those that do not. However, this response is incompatible with the standard treatment of ‘ought’ by theoretical semanticists, who classify ‘ought’ as a member of the family of modal verbs, which are treated uniformly as propositional operators. To many ethical theorists, however, this popular treatment in linguistics seems to elide an important distinction from ethical theory between agential and non-agential ought-statements. The thought is that ‘ought’ might not be multiply ambiguous, but it at least has two senses, one implicating agency and connected to obligations, and another covering other uses.

In this paper, I pursue some resolution of this tension between semantic theory and ethical theory with respect to the meaning of ‘ought’. To this end, I consider what I believe to be the most linguistically sophisticated argument for the view that the word ‘ought’ is ambiguous between agential and non-agential senses. This argument (due to Schroeder) is instructive but based on a false claim about the syntax of agential ought-sentences – or so I attempt to show. Then I use the failure of this argument to motivate some more general reflections on how the standard treatment of ‘ought’ by theoretical semanticists can be refined in light of the distinction important to ethical theory between agential and non-agential ought-statements.