Discourse Topic in Anaphora Resolution and Discourse Construction

Performing the function of encapsulating the whole discourse, discourse topic is usually considered as the center of the discourse. However, the representation form of discourse topic has not been agreed upon due to the elusive nature of the notion per se. Some people view discourse topic as an entity; others regard it as a question; still others as a proposition or even as an unnecessary form. This paper points out that discourse entity cannot be used in event anaphora if it is considered as discourse topic; that if a discourse topic takes the form of question, anaphora resolution may not be realized because of the uncertainty in the question and in the components of the question; and that if a discourse topic takes null form, the global coherence and the relevance of a discourse might be undermined. The paper also proves that comparatively propositional discourse topics conform to human beings' cognitive psychology, contribute to event anaphora resolution and facilitate discourse construction.