Direct Evidentials, Case, Tense and Aspect in Tibetan

The Tibetan evidential system seems to defy systematic analysis. Each evidential category comprises multiple morphemes, and the semantic distinctions that these morphemes encode are often so subtle that native speakers have difficulty explaining them and are often surprised when shown that pairs of morphemes are not intersubstitutable. Nonetheless, careful analysis of these subtle distinctions reveals a surprisingly coherent system, with implications beyond the description of Tibetan. In this paper we sketch that system, focusing on the multiple markers of direct evidentiality. Our account of the Tibetan direct evidential system provides striking support for a theory in which evidence is not a semantic primitive and evidentials encode not evidence type or information source per se, but relations between situations. The Tibetan evidential system comprises three categories: direct evidence, indirect evidence and ego evidence (immediate reflexive knowledge). Within each of these categories several different morphemes encode further subtle distinctions. For example, there are three direct evidential morphemes ( dug, shag and song), shown in (1), which are often, but not always, interchangeable1