Functional Studies On Theory-constitutive Metaphors In Science Discourse

Metaphor plays an extremely important role in our lives. As a phenomenon whereby we talk and, potentially, think about something in terms of something else, metaphor serves as the vital means in our everyday communication. Ever since Aristotle more than 2000 years ago, there has been a vast amount of theoretical discussion on metaphor from various perspectives. But these studies more often than not took metaphor as a means of rhetoric. In 1980s, Lakoff and Johnson proposed conceptual metaphor in their famous book Metaphors We Live By, which brought metaphor study into a new epoch, triggering its cognitive revolution. Lakoff and Johson believe that metaphor is pervasive in everyday life, not just in language but in thought and action. Our ordinary conceptual system, in which we both think and act, is fundamentally metaphorical in nature (Lakoff & Johnson 1980).Within the cognitive framework, metaphor studies have been successfully done concerning its nature, structure, and properties. However, the studies on the functions of metaphor in terms of discourse are comparatively inadequate. In recent years, there has appeared a necessity of the turn of metaphor study to the discourse level. Many scholars (Kittay, 1987, Cameron, 1996, Brown 2003, Semino 2008) have claimed that metaphorical language is encountered, not in isolated sentences, but in contexts of use which can influence discourse goals and also support the demands of discourse processing. Many scholars at home (Wei Zaijiang 2006; Wei Jidong 2005, 2006a, 2006b, 2006c; Wang Wenbin 2007; Liu Guohui, Yu Weishen 2007; Chai Tongwen 2008; Wang Shaohua, Fan Xin 2009; Liao Meizhen 2007) also start to focus on the functions of metaphor within discourse. The thesis will further explore the functions of conceptual metaphors in science discourse.Within the traditional view of science as a neutral and objective activity, metaphor tends to be regarded as irrelevant to science. Recent research, however, suggests that metaphors, especially theory-constitutive metaphors play an important role in scientific research. To some extent theory-constitutive metaphors can be regarded as the engine in scientific theory development. The studies on the functions of metaphor in science discourse mainly concentrate on a certain specific point which is not systematic. Brown (2003) illustrates the function of metaphor from the perspective of history of the development of science and technology and Semino (2008) puts the focus on the ideational function of metaphor in science discourse. Neither of them makes a systematic study in terms of the three functions of language in discourse proposed by Halliday. The thesis will try to explore the theory-constitutive metaphor in science discourse from the perspective of the three functions of language, namely"ideational"function,"textual"function and"interpersonal"function so as to shed some light on the mechanism of metaphors in scientific research and activities.