Abstract

This chapter outlines a theory of propositional attitudes. On this theory, propositions are individuated by their constituent concepts, which are understood as syntactic terms with semantic values. However, the semantic values in question—_Fregean senses_—are individuated more finely than the entities in the world that they are about. Propositions inherently and essentially stand in _conclusive rational relations_ that individuate their Fregean senses and the Fregean senses of their constituents. For example, two propositions have the same Fregean sense if and only if they have the same conclusive rational relations. These conclusive rational relations are ones that a thinker must respect as being capable of having attitudes towards propositions. These rational relations are _conclusive_ in the sense that only via rational compromise can defeaters for their rational commitments arise.