Pragmatics Of Discourse Coherence

The present study, adopting the framework of Relevance Theory and mainly qualitative in nature, intends to investigate the mechanism of discourse coherence. That is, why people organize and interpret discourses the way they do. The issues addressed include the conditions of coherence, the criterion for judging coherence and its degree, and what means people employ to ensure and exploit coherence.The starting point is that discourse production and interpretation are subject to the general principle that governs human communication. Since communication is inferential and context-sensitive, it follows that discourse coherence is the result of the hearer's successful recovery of the implicated premises and conclusion by means of performing inferences. Following Sperber and Wilson (1986/1995), the inference adopted in the present study is non-demonstrative and non-trivial deductive inference and the context is a set of assumptions mutually manifest to the speaker and the hearer.After examining a large number of discourses widely discussed in both the coherence literature and the pragmatics literature, the present study comes up with the following findings.(1) Optimal relevance is the necessary and sufficient condition for achieving discourse coherence in the sense that the interpretation of one utterance yields the assumptions that constitute the context in which the next utterance can achieve adequate contextual effects in exchange for a minimum cost of processing effort. The criterion of coherence is: a) a discourse is coherent if and only if the most salient assumption constitutes, or contributes to, the main idea of the discourse; b) a discourse is coherent to the extent that it conforms to a). A well-organized extended discourse exhibits a hierarchy of assumptions, where sets of elementary assumptions jointly lead to their respective intermediate assumptions, which, in turn, jointly derive the major assumption of the whole discourse.(2)There are two constraints on the selection of contextual assumptions, namely, psychological constraint and linguistic constraint. On the one hand, the Communicative Principle of Relevance addresses both the human cognitive goal of maximally improving its overall representation of the world and the limited time available for instantaneous interpretation of on-going discourses in real-life communication, hence constraining the selection of context psychologically. On the other hand, discourse connectives constrain the selection of context by encoding procedural information about what role the propositions expressed by their home utterances play in an inference, and by reducing the number of possible interpretations that need to be considered.