Reading method for grasping the main points of explanatory texts: extracting important sentences based on contextual effect

Abstract

  Sakuma (1989) has attracted attention as a theory for grasping the main points of explanatory texts. According to Sakuma (1989), it is possible to determine the degree of importance as topic sentence based on the concept of “Tokatsu(Unifying)”. However, its concept remains unclear, and there are cases in which it is not possible to appropriately measure the importance of topic sentences.

  In this paper, I focused on the contextual effect (i.e. improvement of cognitive environment) in relevance theory as the factor that determines the degree of importance of topic sentences. Relevance theory is a framework for understanding the interpretation of utterances/sentences. It was first proposed by Dan Sperber and Deirdre Wilson, and is used within cognitive linguistics and pragmatics. The cognitive effect normally discussed in relevance theory has three types: to support and strengthen an existing assumption, to contradict and rule out an existing assumption, to interact inferentially with existing assumptions to produce a new conclusion.

  By reading explanatory texts, readers can learn something new, become more persuasive, or correct incorrect knowledge (that is, contextual effects can be generated and then the cognitive environment can be improved). Based on this idea, I put forward a theory the degree of importance of sentences as key points in an explanatory text is determined by the degree of improvement in the reader’s cognitive environment. The reason why the reading comprehension method focusing on problem presentation/answer,summary, abstract/concrete, and adversative is effective is that these are related to contextual effect.