Cue reliability, communicative efficiency, anddifferential subject marking: evidence from Korean

This article investigates the role of situational context in differential case marking. Evidence from conversation data in Korean demonstrates that caseless subjects are predominantly found in event-reporting clauses that have an agent directly identifiable in the here and now, while casemarked subjects are not similarly restricted. Based on this evidence, I propose a new account of differential subject marking in terms of an efficiency principle of negative correlation between length/complexity and cue reliability. I argue that the association of caseless subjects with seemingly unrelated features such as grounding in the here and now, nonstativity, and definiteness follows from speakers’ efficient use of case marking motivated by the availability of strong situational cues to the intended role interpretation of a subject referent.