On Alfred Tarski’s Semantic Theory Of Truth

Alfred Tarski was one of the greatest logicians of all time. Along with his contemporary, Kurt Godel, he changed the face of logic in the twentieth century, especially through his work on the concept of truth and the theory of models. Tarski’s Semantic Theory of Truth and Godel’s Incompleteness Theorem, Turing Machines known as the three major achievements of modern logic. The greatness of Tarski’s semantic of truth theory not only lies in it grounds the basis of modern logical semantics,but also lies in it arouses people thinking some important philosophical problems. Therefore, my paper is mainly research Tarski’s semantic theory of truth and some philosophical problems that caused by this theory.Frege had put forward some thoughts of semantics before Tarski constructed a semantics theory. Frege strictly distinguished sentence’s sense and meaning, he hold that a sentence’s sense is thought, but a sentence’s meaning is truth value. And thought is the content of a sentence, sometimes it also can be called as propositions; while truth value is refers to true or false of a sentence. Compared to the sense of a sentence, we concerned more about a sentence’s meaning, because sentence’s meaning is truth value and asking for the true of a sentence makes us transform to the thinking of science. Although Frege put forward some thoughts of semantics, he neither constructed a systematic semantics theory, nor did he answer clearly what’s semantics. Tarski constructed a systematic semantic theory when he was explaining the definition of a true sentence in a given language, which grounds the basis of modern logical semantics.In1933, Tarski published an article The Concept of Truth in Formalized Languages, in which Tarski firstly negated the possibility of defining truth in natural language, then he made a distinction between meta-language and object-language and offered a materially adequate and formally correct definition of the’true sentence’by using the satisfaction concept, and finally formed Tarski’s semantic theory of truth. Tarski’s semantic theory of truth established the foundation of modern logic semantics, promoted the development of truth theory and meaning theory, improved the development of empirical science and deductive science.Though Tarski have given the definition of a true sentence in formalized language, whether he completely explained the concept of true when "true" was applied to the definition of a true sentence that formed by sentence? There are well-known words in Aristotle’s Metaphysics:To say of what is that it is not or of what is not that it is, is false, while to say of what is that it is, or of what is not that it is not, is true. According to Tarski, the old famous saying of Aristotle expressed the intuition of this concept "true" very well.And such an intuition is a correspondence of statement and fact. The carrier of concept "true" is statement, and a statement is not only express a sentence, but also maybe a judgment or proposition. So to explain the concept "true’", we have to consider a statement is a judgment or a proposition. But Tarski see statement as only a sentence, and whether statement is a judgment or a proposition is beyond his consideration. Therefore, we believe that Tarski have not completely explained the concept "true", he just gives an epitaxial truth’s definition of a statement is a sentence. But it is possible to give the definition of truth’s judgment or truth’s proposition in the sense of statement. Tarski’s definition of truth’s sentence grounds the basis of realizing the definition of truth’s judgment or truth’s proposition in the sense of statement. A statement is true, if and only if the sentence、judgment or proposition expressed by this statement is true.Now that the intuition of grasping the concept true lies in grasping the correspondence relationship between statement and fact, whether a true statement can make us realize the correspondence between statement and fact? To answer this question, our strategy is return to Tarski’s theory of the semantic of truth. Because Tarski’s definition of true sentence is the basis of explaining the statement of truth, so that if Tarski’s theory of the semantic of truth is a correspondence theory, then naturally we can conclude that the truth of a statement means this statement conforms to fact.Whether Tarski’s theory of the semantic of truth is a correspondence theory? Those who believe Tarski’s theory of the semantic of truth is a correspondence theory seem to always insist that Tarski’s condition of truth have given an explanation of true conforms to fact; But for those who don’t believe it and even think that Tarski’s theory is not a correspondence theory but a deflation theory, they seem to always think that we can use a sentence perfectly instead the sentence that have quotation marks and following "is true" behind, so the predicate "true" can be eliminated. Certainly there are some other people to judge whether Tarski is a correspondence theorist based on Tarski’s arguments of his articles.According to the analysis of redundancy theory and deflation theory, we think that we can find the difficulties of the two theories facing by the aid of Tarski’s theory of truth. Among typically is using the relevant sentences or relevant words such as "conclude"、"determine" etc.To eliminate the predicate "true" will encounter kinds of difficulties, even leads to some contradictory or anti-intuition conclusions. Therefore, as for the predicate"true", our position is predicate "true" cannot be eliminated, and consider Tarski’s theory of truth as a deflation theory or redundancy theory is not proper.As for the correspondence theory, we think if Tarski’s theory of truth explained some problems that correspondence theory encountered, his theory ought to be a correspondence theory. Correspondence theory facing the problem of needing to explain fact concept and correspondence concept, also facing the problem of explaining the correspondence relationship between proposition and fact is one-to-one relationship or other relationship. But in Tarski’s theory of truth,Tarski’s definition of truth explained what is fact.and through Davidson’s view of being able to explain concept "true" in the passage of natural language.we hold that Tarski’s condition of truth explained what is conform to fact. And because what Tarski defined is a sentence’s definition of truth, therefore, we think that what he explained is correspondence relationship between sentence and fact, and it’s a many-to-one relationship. So we believe Tarski’s theory of truth explained some problems that correspondence theory encountered, and his theory is a kind of correspondence theory. Besides, based on one of Tarski’s views, that is, he is only want to grasp classical concept of truth that true conforms to fact, but not concept of truth that true plays role in a certain aspect, we imagine it is seem to suggest the word "true" plays the role of making us understand a statement conforms to fact from the function of truth. Through the analysis above, we finally suggest Tarski’s theory of truth is a correspondence theory, predicate’true" cannot be eliminated, because predicate "true" guaranteed a sentence’s consistency epitaxial in a sentence, and make us understand the correspondence of a statement and fact.Since Tarski’s semantic of truth theory is a kind of correspondence theory, and because explanation of a true statement is based on Tarski’s definition of true sentence and the definition of judgment of truth and proposition of truth that formed by the definition of true sentence, so the truth of a statement means this statement conforms to fact, and grasped a true statement is grasp the intuition of concept "true"The reason why Tarski choose a formalized language to explain "true", that’s because he thinks explaining "true" in natural language will result in the appearance of semantic paradox, so he holds a pessimistic attitude towards explaining"true" in natural language. Tarski further put forward a thought of language stratified to explain semantic paradox. But such thought against people’s intuitive using the concept "true" in natural language. We use Kripke’s thought of returning natural language to explain semantic paradox for reference, and standing the basis of Davidson’s views, we think that we needn’t to be pessimistic as Tarski, but can discuss "true" in the passage of natural language. The advantage of this is that we can explain some semantic paradox in the passage of natural language, and such an explanation wills not against people’s intuitive using the concept "true" in natural language.