 The Frege-Geach Objection. Because Stevenson’s theory is often thought to succumb to the Objection from Instrumentalism, it is also thought to succumb to the Frege-Geach Objection, perhaps the most pressing objection to any emotivist or expressivist theory of meaning. This objection is so-called because Peter Geach (1958, 1960, 1965), relying on insights from Frege (e.g., 1918), argued persuasively that a sentence’s illocutionary force cannot constitute its meaning. The strength of the Frege-Geach Objection arises from the fact that natural languages are compositional and, thus, that a minimal condition of adequacy on any semantic theory is that it specify that which sentences contribute to the more complex sentences into which they are embeddable. For example, a minimally adequate semantic theory for English will entail that the meaning of sentence 1. remains the same when it is embedded within sentences 2. or 3., since an understanding of the latter sentences rests on an understanding of their respective parts, including 1., and of the significance of the way those parts are combined. However, since (it is thought) Stevenson’s theory of meaning holds that moral sentences are used to express a speaker’s attitudes—i.e., used with expressive illocutionary force—and since moral sentences are often used as parts of more complex sentences without such expressive force, as in sentences 2. and 3., Stevenson has failed to provide a minimally adequate theory of meaning for moral sentences.