The unity of the proposition

In 1910 Bertrand Russell abandoned the theory of propositions that he advocated in 1903 in The Principles of Mathematics because of the problem of the unity of the proposition. This is the problem of explaining how the constituents of a proposition are bound together into a unified, representational whole. This problem has largely been ignored by contemporary advocates of Russellian propositions. I argue that (i) this problem is the result of the Fregean distinction between content and force, (ii) the arguments for the content-force distinction are inconclusive and (iii) there is independent linguistic evidence against the content-force distinction. For these reasons I think that Frege's distinction between content and force should be abandoned; this is the main negative conclusion of the dissertation.; The main positive component of the dissertation is an account of structured propositions that individuates propositions in terms of force or mood. On the account I defend, propositions are types of representational actions or states. The proposition expressed by 'Jones loves Smith', for example, is a type of representational state, tokens of which are particular assertions that Jones loves Smith or belief-states that Jones loves Smith. The proposition expressed by 'Does Jones love Smith?', on the other hand, is a type of interrogative action or state, tokens of which are instances of asking whether Jones loves Smith or wondering whether Jones loves Smith. This account solves the problem of the unity of proposition by locating the unifying element in a proposition in an act of the subject. In addition, this account provides an empirical foundation for semantics. A semantic theory, on this view, is a theory of what speakers do with sentences in contexts. To say that a sentence S expresses a proposition p in context c is to record a fact about the literal and direct illocutionary act that could be performed using S in c.