A Study Of Metaphor In EST Discourse

Language, as German philosopher Ernest Cassirer argues, is by its very nature and essence, metaphorical. In this sense, metaphor not only occurs in literary language, but also occurs in daily language as well as in scientific language. In terms of cognitive linguistics, metaphor has become a major cognitive tool and help people describe the various phenomenon or discoveries in scientific and technologic field in concise and appropriate language. However, much of the discussion is undertaken with regard to the metaphor occurring in literary texts and daily conversation, therefore, the study of metaphor in scientific language is quite necessary. Considering the hegemonic status of English in scientific field, this thesis attempts to explore the functions of both lexical and grammatical metaphors in English discourse for Science and Technology(EST discourse) under the guidance of cognitive linguistics and Halliday's theory of grammatical metaphor.Metaphor has engaged the attention of many researchers since ancient times. The earliest study on metaphor can be traced back to the ancient Greek Philosopher Aristotle. In traditional rhetorical approach, metaphor is regarded as a rhetorical device to achieve certain effects or even a kind of decorative addition to ordinary plain language. However, modern cognitivists such as Richards (1936), and Lakoff and Johnson (1980) view metaphor as a cognitive mechanism whereby more abstract and intangible areas of experience can be conceptualized in terms of the familiar and concrete. Metaphor in this sense is not just a matter of language, but of thought and action. What's more, M.A.K .Halliday put forward the theory of grammatical metaphor, which greatly broadens the view of traditional study of metaphor and the concept of grammatical metaphor deepens our understanding of metaphor.As a cognitive mechanism, metaphor occurs in abundance in EST discourse at both lexical level and grammatical level. Lexical metaphor refers to the word used for something similar to what it refers to. Ontological, cultural and creative metaphors are analyzed by means of instantiation. Through the analysis, the author holds that similarity is a crucial feature of lexical metaphor and the lexical metaphors in EST discourse are either similarity-based or similarity-creating in nature. Grammatical metaphor refers to the variation in grammatical forms to express a given meaning. The author adopts quantitative method to count the occurrence frequency of lexical metaphor and each type of grammatical metaphor in EST discourse. The statistic results show that the number of lexical metaphors is much less than that of grammatical metaphors and the frequency of grammatical metaphor in EST discourse is affected by its professionality and complexity. The author further compares lexical metaphor and grammatical metaphor and argues that although lexical metaphor and grammatical metaphor operate in different manners, they have at least three similarities. Then, the author borrows Halliday's terms for metafunctions of language to analyze the ideational function, interpersonal function and textual function of metaphor respectively. It is found that both lexical metaphor and grammatical metaphor are important linguistic resources to create technical terms and constitute scientific theories. By borrowing the familiar terms, lexical metaphor renders the scientific discourse more comprehensible so that the intimacy between the writers and the public readers is reinforced; while grammatical metaphor keeps the formality and technicality of scientific discourse, and thus maintains the authoritativeness of scientific language in the minds of the public on the one hand and strengthens the sense of belongingness of the scientist and his peers on the other hand. Both lexical metaphor and grammatical metaphor contribute to the composing of a coherent scientific discourse. The author further demonstrates the study results of this thesis by choosing a scientific article as a study case.In all, this thesis finds that metaphor, especially grammatical metaphor is widely used in EST discourse, and both lexical metaphor and grammatical metaphor play important roles in the perfection of scientific discourse. It is believed that the study of this thesis will help readers get a better understanding of metaphorical phenomenon in scientific English.