Talk by Robert R. Westmoreland
Epistemic {\em Must\/} as Evidential
Possible-world semantic and Update Semantic accounts of epistemic {\em must\/} fail
to make the proper distinction between MUST P and simply P. The behavior of
epistemic {\em must\/}, which distinguishes it from might on the one hand and from
non-epistemic {\em must\/} on the other, indicates that it is not the dual of might
as commonly thought, or even a true modal. Rather, it is an evidential,
labeling a proposition as being a (non-logical) inference. Evidentials are a
widespread class of morphemes cross-linguistically, and do not contribute to
propositional content or context change potential, but rather indicate source
of information.
Paul Dekker, November 2, 1995