This dissertation consists of three independent papers that are linked by two threads. The first thread is the question of what sorts of explanatory roles can be played by propositions and semantic values. The first paper, “Doing without Minimal Propositions”, explores this question by looking at the role of semantic values in conversation, in particular examining the claim that only a small range of linguistic expressions need context in order for sentences containing them to have a proposition as their semantic content. I argue to the contrary that the largely context-insensitive propositions posited by such a view are not needed to explain the range of linguistic facts that motivates them. My second paper, “Problems for Metasemantic Ex...