Causality and aspect in ability, actuality, and implicativity

Abstract

Past-tense ability ascriptions (e.g., "was able") alternate between pure, potentially unrealized ability and an interpretation which actualizes the ability. The alternation extends to abilitative uses of possibility modals, with actualized readings strengthening to actuality entailments under perfective aspect in aspect-marking languages (Bhatt 1999). These interpretations resist explanation on accounts which seek to derive them in the composition of modality and aspect. I build on causal analyses of implicative inferences (from lexical implicatives like "manage" as well as 'variably-implicative' "enough" comparatives; Baglini & Francez 2016, Nadathur 2016, 2017) to propose a new approach to actuality inferences, grounded in a causal semantics for ability predicates. This account derives both pure ability and actuality readings, and explains parallels between implicative "manage" and actualized ability on the basis of shared (presuppositional) causal structure. "Manage" and ability differ in asserted content, but the difference is neutralized – producing actuality entailments – under a perfective operator which selects for eventive predicates, and combines with stative ability attributions only via aspectual coercion.