Coherence, From A Cognitive Perspective

It has been decades long since coherence as a term was borrowed from Greek rhetoric into modern linguistics. During these decades, different scholars have carried out their studies from different perspectives. Some scholars (Halliday and Hasan, etc.) have studied coherence from cohesion; some (Danes and Fries, etc.) from thematic progression, some (de Beaugrande and Dressier, etc) from semantic relationships, and some (van Dijk and Kintsch, etc.) from "macro-structure and micro-structure" and proposition, while others (Widdowson, etc.) have studied coherence from adjacency pairs, the cooperative principle and speech acts, taking participants' interactions and interpretations into consideration. Though the studies of coherence have gained great achievements, they fail to explain the mental process of coherence. Some scholars (Zhang Ren-xian, Givon, etc.) have also studied the degree of coherence, but they take repetition as the basis of their analyses.This thesis makes an attempt to explain coherence in a relevance-based approach. Relevance Theory proposed by Sperber & Wilson has an explanatory power of the mental process of language. Sperber & Wilson hold the view that verbal communication is an ostensive-inferential communication in a chosen context made up of a set of contextual assumptions, abiding by the Optimal Relevance Principle. Coherence, derivable from relevance, is divided into two kinds: the coherence of propositional content and the coherence of contextual effect. When the succeeding sentence is understood with the help of the preceding one, it is coherent; when the succeeding sentence, combined with the contextual assumptions formed by the preceding one, produces contextual effects, it is coherent.Coherence is judged in a general way. Text with linguistic mistakes and interruptions are often judged as coherent. But sometimes these judgments on discourse coherence contradict the analysis of the relevance-based approach.This contradiction is connected with readers' (listeners') view of what is the basic unit of linguistic analysis. The relevance-based approach processes text from sentence tosentence. In fact, a text can be analyzed independently, but sometimes it can also be treated as a unit of a large text (super-text), sometimes it contains some smaller ones (sub-text). Therefore, a text will be treated as coherent on one level and incoherent on another level; the different evaluations are connected with readers' (listeners') view of the text and its contextual assumptions. From the analyses, the initial relevance-based to approach to coherence is modified. According to the modified approach, if the succeeding sub-text, combined with the contextual assumptions formed by the preceding sub-text, produces contextual effect in a text, the text is coherent. Coherence is also affected by the contents of contextual assumptions and the contents of text.