This chapter concerns David Kaplan’s arguments that we need to postulate temporal propositions as the meanings-in-context of some natural language sentence, more precisely some sentence with temporal context dependence. Kaplan’s arguments concerns the rejection of vacuous temporal operations and the compositionality of content, i.e. meaning-in-context.

We shall present the arguments, some of the reactions to them in the literature, and our own Switcher Semantic solution, which combines classical propositions with general compositionality of content.