| Punning has experienced a long history in English. It is one of the most commonly used figures of speech and welcomed by many people both in the ancient and in the modern times, both in the literature works and in the daily communications. The traditional study of English puns focuses mainly on the structure, functions, types and scopes of puns, paying attention to the language phenomenon rather than the psychological mechanism of pun production and understanding. This thesis tries to talk about the mechanism from cognitive and pragmatic perspectives within the framework of Relevance Theory (RT for short).This thesis firstly introduces the definitions of pun from different sources and its features, and then reviews the literatures that studied puns from the rhetorical, semantic or pragmatic point of view, pointing out their contributions and shortcomings. After that we introduce the Relevance Theory, including its background and the main points.The main part of this thesis lies in the analysis of the psychological mechanism of the pun production and understanding from cognitive and pragmatic perspectives. As far as the producing mechanism is concerned, in the cognitive perspective, through analyzing, we find out that pun is a form of metaphor. By saying"metaphor"we do not mean the traditional point of view to regard metaphor as a figure of speech, we refer to the idea of Lakoff & Johnson that sees metaphor as a way of thinking and a method of cognition. As a pun involves two mental spaces just as a metaphor does, the psychological mechanism of a pun is same as that of a metaphor. As a kind of metaphor, the phonetic metaphor utilizes the similarity in phones to realize the metaphor. And the pun is a representation of phonetic metaphor. From the pragmatic perspective, the pragmatic effects are discussed. Since the pun is a violation to Grice's cooperative principle, in which the manner maxim states as"to avoid ambiguity", why dose it exist? Why does the speaker say so? Through discussion, we find out the pragmatic functions of puns, which make it obtain a better pragmatic effect than the normal use. The pragmatic functions are: to indicate the economy of language; to produce a humorous effect; to multiply the literature effect of the text; to attract the attentions. After that, RT is used as the framework. As RT holds, communication is an ostensive-inferential process. The production and interpretation of a pun follows this process. For the addresser, he intentionally uses the ambiguous words or similar sounds to make a pun, which violates the manner maxim. By intentionally using this marked form, the addresser tries to show his intentions, and the addressee tries to work out the intentions by inferring from the context and complete his cognitive task of finding out the connections between the two senses of the pun. As for the interpretation of a pun, there are five steps for the hearer to understand a pun in the framework of RT.Finally, the thesis points out limitations of the study and gives some suggestions for further studies. |