Definability and Undefinability of Truth

This thesis will focus on Tarski’s work, so the Section 2 starts with him, giving an overview of the elements of his theory of truth, leading to a presentation of his theorem in 2.3. In the rest of the paper, proposals for solving the problem of internalization of the concept of truth and the paradoxes arising from this problem with some of the proposed solution are considered. Section 3. will quickly introduce the Liar paradox and once more explicitly state Tarski’s solution, followed by the so called “revenge of the liar”; a liar type sentence which cannot be avoided even by using Tarski’s solution to the original liar. After that, Section 4. will introduce Kripke’s Theory of Truth and his take on truth and solving t he Liar paradox using paracomplete logic, while Section 5. will examine some further attempts in answering the aforementioned problems in the context of paraconsistent logic