It is a common view among philosophers of language that both propositions and sentences are structured objects. One obvious question to ask about such a view is whether there is any interesting connection between these two sorts of structure. The author identifies two theses about this relationship. Identity (ID) – the structure of a sentence and the proposition it expresses are identical. Determinism (DET) – the structure of a sentence determines the structure of the proposition it expresses. After noting that (...) ID entails DET, the author argues against DET (and therefore also against ID). This argument is based on considerations to do with unarticulated constituents, but it is not ultimately empirical. As well as answering a question suggested by contemporary theories of propositions, the conclusion is significant because some, but not all, of the theories of propositions currently popular entail ID and/or DET. Unless there is a response to the argument here, those theories are refuted. (shrink)