Strict Comparison and Weak Necessity: The Case of Epistemic Yao in Mandarin Chinese

摘要

The epistemic use of yao in Mandarin Chinese, often translated as 'should' in English, shows certain interesting peculiarities. In this paper, I first describe the empirical properties of epistemic yao. The occurrence of epistemic yao is restricted only to certain comparative constructions, but forbidden in other degree constructions or non-degree constructions. It cannot appear above or below negation. It has a quantificational force stronger than that of existential modals, yet weaker than that of strong necessity modals. It can appear with another epistemic modal yinggai, which has a very similar modal flavor and an identical quantificational force. When co-occurring, however, the two epistemic modals have to follow a strict word order. Next, I examine whether the above empirical properties of epistemic yao arise as lexical idiosyncrasies, from syntax, semantics, or their interface. Wherever relevant in the discussion, I compare epistemic yao to the (near-)synonymous yinggai. The epistemic use of yao in Mandarin Chinese may constitute an interesting case of inter- and cross-linguistic variation in natural language modality.