All too often when philosophers talk and write about sentences, they have in mind only indicative sentences, that is, sentences that are true or false and that are normally used in the performance of assertions. When interrogative sentences are mentioned at all, it is usually either in the form of a gesture toward some extension of the account of indicatives or an acknowledgment of the limitations of such an account. For example, in the final two sentences of his influential paper "Truth and Meaning" (1967), Donald Davidson remarks, "And finally, there are all the sentences that seem not to have truth values at all: the imperatives, optatives, interrogatives, and a host more. A comprehensive theory of meaning for a natural language must cope successfully with each of these problems." Nonindicatives are an embarrassment to Davidson's program of identifying meaning with truth conditions. They are equally an embarrassment for the...