What Is Truth?

In the academic field of philosophy and logic, the "truth" is one of the core concepts, which becomes more prominent after Frege propses mathematical logic. Tarski put forwards the Convention T from the perspective of formal language,and give the truth a formal definition.Davidson agrees with it, but he doesn’t satisfy that the Convention T is limited in formal language and he insist the Convention T extend into the natural language. Therefore, Davidson revises the Convention T and tries to contact it with the theory of truth.This paper will attempt to explain the develoption from the Tarski’s definition to Davidson’s theory of truth,discover the logic relation between the two of them, and finally integrate them.The thesis can be devided into the following five parts:first, The introduction introduces the reason and significance of the article, the relevant study of the topic in academic world. The second part gathers up the Tarski’s theory of truth via five parts. The third part points how Davidson evaluate and modify the Tarski’s theory of truth. The fourth part mainly discusses Davidson’s theory of truth. In the last part, some further discussions.