Alice ter Meulen (Geneva): Indexical Inference

Inferences are considered indexical, when their conclusion introduces a new expression, not given in the premisses, whose interpretation depends on extra-linguistic, situational parameters. We investigate how the indexical meaning of the English aspectual adverbs already, still, no longer and not yet, modifying numerical determiners, supports the introduction of predicates such as arrive and leave as backgrounded information. DRT accounts for certain unacceptability facts and accommodates the speaker subjective information, when these adverbs are used with marked prosody. A full-fledged theory of indexical inference requires a much more sophisticated understanding of the dynamics of indexicals in discourse, including a theory of temporal reasoning based on our notion of a chronoscope.