The Notional Category of Modality 论文

摘要

Abstract The chapter derives a typology of possible modal expressions from three parameters: modal base, ordering source, and modal force. Modal bases represent the factual premises the truth of a modal statement might depend on: pieces of evidence or inherent properties of individuals or situations. Ordering sources represent non-factual, typically normative, premises. Modal force relates to the difference between possibility modals, necessity modals, and degree modals without duals. Depending on the language and syntactic category, modals also participate in comparative constructions. Modal bases and ordering sources are modeled as premise set intensions, functions from worlds to premise sets. Jointly, modal bases and ordering sources are responsible for a modal's flavor: circumstantial, epistemic, deontic, teleological, bouletic, and so on. Ordering sources induce orderings on the sets of worlds determined by modal bases. Those orderings can then function as launch pads for comparative and quantitative modal notions related to capability, feasibility, probability, and desirability. Separating factual and non-factual premises also helps with practical reasoning, and delivers a unified account of indicative and subjunctive conditionals. Counterfactuals, deontic conditionals, probability conditionals, and indicative conditionals with interpretations ranging from material to logical implication can now be uniformly interpreted as cases of restricted modality.