On Implicit Coherence In Discourse

'Coherence' is not only an important concept in linguistics but also an important part of discourse study. It is much more concerned with connectivity, acceptability, and unity of discourse. Its process involves both linguistic and non-linguistic factors. It can be divided into explicit coherence and implicit coherence. Explicit coherence is supported by cohesive devices, namely reference, substitution, ellipsis, lexical cohesion and conjunction. The presentation of implicit coherence is based on the doubts cast on the Halliday's Cohesive Theory. As opposed to explicit coherence, it is put forward and referred to unified semantic relations supported by non-linguistic factors. It has three features: 1.it is covert; 2.it is exophoric; 3.it is cognitive.The emergency of implicit coherence is not arbitrary. In a sense, it is attributed to language evolution. Language is socially developed and becomes diversified and complicated. During the evolution, people employ various forms of language to perform social functions and convey their feelings. As a result, the diversity of linguistic forms makes it possible that 'implicitness' and 'explicitness' of language can coexist. The distinction between implicit coherence and explicit coherence is not absolutely clear-cut so it is necessary to make further clarification about implicit coherence. In fact, implicit coherence is a matter of degree in semantic connectivity of discourse. Usually in a discourse, explicit coherence has the strongest cohesive force, and implicit coherence ranks the second and non-coherence is the weakest for it has hardly any cohesive force. In terms of the relation between implicit coherence and implicit conjunction, they are both correlative and differential. Mere implicit conjunction can lead to implicit coherence but it is neither necessary nor sufficient to the emergency of implicit coherence.Utterances are conceived as the main channel available to the nature of language so it is our foremost concern to give a reasonable interpretation of implicit coherence. Fortunately, the development of relevance theory (RT) has contributed sufficiently to the interpretation of implicit coherence. Compared with implicatures and schemata, optimal relevance is the fundamental rationale to reveal the truth of implicit coherence.As a literary genre, poetry is unique in form, deep in thought and delicate in emotion and becomes the source of the creation of implicit coherence. Besides, it is also a kind of discourse and of course becomes our concern. The interpretation about implicit coherence in English poetry is a special case complementary to the study in utterances. It is suggested that there should be surface reasons and deep reasons for the emergency of implicit coherence. Surface reasons include image, metaphor and deviation of the poem; deep reasons include poet's extreme idiosyncrasies, inconsistent register of the poem and its recreational function. The study of implicit coherence reveals the duality of coherence: explicitness and implicitness, and at the same time it further proves the dialectic unity of language development—implicitness and explicitness coexist and equally develop. The further study of implicit coherence will shed light on discourse analysis and drive the study of discourse coherence toward a higher level.