Assessing the modality particles of the Yi group in fuzzy possible-worlds semantics

Of late, evidentiality has received great attention in formal semantics. In this paper I develop 'evidentiality-informed' truth conditions for modal operators such as must and may. With language data drawn from Luoping Nase (a Tibeto-Burman language spoken in the P.R. of China and belonging to the Yi Nationality), I illustrate that epistemic modals clash with clauses articulating first-hand information. I then demonstrate that existing models such as Kratzer's graded possible-worlds semantics fail to provide accurate truth conditions for modals tagging clauses with first-hand information. As a remedy I propose a fuzzy version of possible-worlds semantics with various grades of belief and knowledge. In addition to preserving the expressive power of graded possible-worlds semantics, the fuzzy model will be shown to supply appropriate truth conditions for epistemic modals appended to evidential clauses (i.e. clauses expressing first-hand information). © Springer Science+Business Media B.V. 2009.