A Functional Analysis Of Ideational Metaphor In Scientific Discourse

Because of its high abstraction and complexity, scientific discourse often acts as an obstacle for the foreign language learners in the process of learning English. Therefore, this thesis attempts to analyze samples of scientific discourse on the basis of grammatical metaphor theory.Grammatical metaphor is initiated by M.A.K. Halliday in 1985. He interprets metaphor from two perspectives: lexical metaphor and grammatical metaphor. In this thesis, the explanation of grammatical metaphor involves two aspects. First, Halliday considers language as a tri-stratal system: semantics, lexicogrammar and phonology. And the one-to-many relationship between semantics and lexciogrammar makes grammatical metaphor possible. Second, according to the metafunctions of language, grammatical metaphor can be classified into ideational metaphor, interpersonal metaphor and textual metaphor.Thirteen types of ideational metaphor are applied to analyze six scientific texts. Through the statistic analysis, we find that nominalizations occupy a central role in each of them. Nominalizations can pack the clauses into nominal groups and perform powerful cohesive function in the discourse, but give rise to the abstraction and complexity of the discourse. So in the writing of scientific discourse, the employment of nominalizations should be emphasized. While in the reading of scientific discourse, nominalizations can be unpacked and restored, which will be very helpful to our understanding.