Sharif Digital Repository

This dissertation consists of five parts. In the fist part we draw a scheme of Logical Paradoxes: What is a paradox, what are logical paradoxes, different versions of logical paradoxes, etc. The three next parts are respectively about: Tarski’s Hierarchy Approach, Kripke’s Fixed Point Theory and Herzberger and Gupta’s Revision Theory of Truth. In the end of each of these three parts, we consider some critics. In the last part, we introduce our new approach. This is based on a new concept called Pseudo-Contradiction. Relative to a (consistent) set S of axioms, a sentence φ is a Pseudo-contradiction if and only if both φ and ¬φ are inconsistent with S. We try to show the Liar sentence can be...