Study On Presupposition,Semantic Entailment And Approach Of Discriminating Them

Semantic Presupposition and Semantic Entailment are two closely related concepts. To discriminate them will be helpful to understand and use the natural language. And the key of discrimination is defining perspicuous, making the relation clearly and discriminating the approach useful. But the original differentiations have some problems on the three ways. It brings some difficult for discriminating accurately. So, we should to research the things of Presupposition, Semantic Entailment and discriminating the approach and point out the essence on it and replenish the existential approach. For it, here discuss mainly the following questions:1. The definition of Semantic Presupposition and Semantic Entailment. Inthe part, we discuss the definition, kind and characteristic of the two fundamental concepts and give the fit definition. I think it is not perfect one the logic deflnition of Semantic Presupposition is used widely and the Semantic definition of Semantic Presupposition is the definition accurately for it. For the Semantic Entailment, we should exceed the view that the sentences are true and their Semantic Entailment is true. However, if thesentences exist, their Semantic Entailment exists.2. The relation of Semantic Presupposition and Semantic Entailment. Inthe part, we analyze the relation between the logic definition the Semantic Presupposition and Semantic Entailment and analyze the relation between the Semantic definition of it and Semantic Entailment. Then, we explain the relation of them: the extensive entailments include presupposition and the narrow one is different from presupposition. We think the essence of discrimination is to identify the Semantic Presupposition and discuss the errors in the process.3. The existential approach of discrimination of Semantic Presupposition and Semantic Entailment. In the part, we analyze detailed the foundations, essentials and limits about truth-value comparing, negationtest, conjunction test, embedding technique. By analyzing the problems, we think the essence of the preceding three approaches is same and they all on the basis of the truth-value characteristic of Semantic Presupposition and Semantic Entailment and they all discriminate the logic definition the Semantic Presupposition. So, the discriminating range are almost consistent and the approach isn't complemented each other. The Embedding technique isn't used widely for its complex conduct. It is helpful to choose them for using that we discuss the range and limit of the existential approach.On the basis of the above discussion, we give the initial conclusion: it is difficult to complete the discrimination between Semantic Presupposition and Semantic Entailment with a simple formula approach. And we should do it from various aspects. Firstly, it include that we can give an judgment according to the deep comprehension about the definition, kinds and characteristic of Semantic Presupposition and Semantic Entailment for some Semantic Presupposition, for example, Existential Presupposition, without the existential approach. Secondly, it include that we can discriminate some typical Semantic Presupposition with the existential approach. Thirdly, it include that we can discriminate them according to the preexistence of Semantic Presupposition and the analyzing the meanings of sentences as complements of the existential approach. In the discriminating process, we can improve the accuracy combining the preceding three aspects.