It is obvious that CP can play a significant role in explaining how conversational implicature is generated. However, it is far from enough to explain why people always do not express what they think in their inner world in a direct way and why people prefer to tell things by violating some maxims so as to express in an indirect way. In order to know the answer, great efforts have been made, among which the Politeness Theories proposed by Leech and Brown are of great significance. Leech (1983) proposes PP in an attempt to rescue Grice’s CP. Leech suggests that speakers often violate the principle of cooperation out of politeness. It is out of consideration of politeness that people prefer to choose different pragmatic strategies to obey or violate CP.
As mass media gain increasing popularity, more and more people tend to watch a movie during their spare time. And superhero movies has been popular for quite a long time. But Chinese viewers sometimes fail to understand the movies due to the abundance of Conversational Implicature in them. Grice first put forward the hypothesis of Cooperative Principle when he gave a lecture at Harvard University in 1967. The hypothesis consists of four maxims, namely, Quantity Maxim, Quality Maxim, Relation Maxim and Manner Maxim. Cooperative Principle theorizes on the rules followed by people conducting their day-to-day communication. However, people constantly violate this principle for specific purposes. The present study conducts a case study of Iron Man 3 from the perspective of Cooperative Principle in order to reveal the conversational implicature in this movie. This paper attempts to analyze Iron Man 3 from the perspective of Cooperative Principle, providing a new angle for the study of characters’ utterances in audiovisual works.
1.2    Aim and Significance of the Study
This paper aims to analyze the Conversational Implicature in the superhero movie Iron Man 3 from the perspective of Cooperative Principle. It focuses on how Cooperative Principle influence the Conversational Implicature in this movie through the observance and violation of Quantity Maxim, Quality Maxim, Relation Maxim and Manner Maxim.
Conversational Implicature was first put forward by the well-known language philosopher Grice. Until now, Conversational Implicature analysis is gradually taking more proportion when doing research in linguistic area. This paper is based on the theory of pragmatics, using Cooperative Principle to analyze the conversation in Iron Man 3, so as to deepen our understanding of the American Superhero Culture and Values under the background of modern American society. At the same time, we could understand the whole plot and information of the communication. This theme has both theoretical and practical importance in foreign language teaching and learning.   
1.3    The Overall Structure of the Paper   
There are four parts in this paper. Part One is a brief introduction of the study, including the research background, the aim and significance of the study and the overall structure of the paper. Part Two is the literature review, explaining the key terms in the study and introducing previous studies on similar topics. Part Three presents a detailed analysis of conversational implicature in the movie Iron Man 3 from the perspective of Cooperative Principle. The last part is the conclusion. The limitation of this paper and some suggestions are given for further research on Iron Man 3. 合作原则视角下《钢铁侠3》中的会话含义分析(2):http://www.youerw.com/yingyu/lunwen_48074.html