The Interaction of Conditionals, Modals, and Mood

Abstract

The dissertation is a study of the ways in which counterfactual possibilities are contrasted with the actual world in modal and conditional linguistic environments. Many modal and conditional sentences include embedded phrases that are evaluated at the actual world rather than at the possible worlds relevant to the truth of the overall sentence. This allows us to use language not merely to describe possibilities but also to make explicit comparisons and contrasts between counterfactual possibilities and the actual world. It is argued that the linguistic phenomena observed in sentences of this kind are problematic for the theoretical framework according to which modals are sentential operators. Instead, they support a view according to which language contains variables for possible worlds which can be either bound or left free by modals. This has the consequence that sentences do not vary in truth-value across possible worlds, which in term has implications for the theory of assertion and meaning more generally. It is also argued that <italic>actually</italic> is not a modal, and that the role generally assumed by philosophers to be played by <italic>actually</italic> is in fact played by embedded sentences with different combinations of grammatical mood. Along the way, a number of syntactic and semantic analogies between modality and tense are examined and their consequences for various theories of conditionals are explored.