On the structural properties of paradoxes: the distinction between formal language and natural language that comes with the use of the liar paradox


Murat Kelikli


This study delves into the intriguing realm of paradoxes that have long fascinated philosophers and logicians throughout history. It begins by discussing the nature and purpose of paradoxes, ranging from their role in entertainment to their capacity to reveal flaws within logical systems. This work emphasizes the challenge paradoxes pose to the completeness of systems and the subsequent development of axiomatic systems that aim to eliminate paradoxes. Rather than providing definitive solutions to paradoxes, the primary aim of this study is to defend the idea that systems containing paradoxes can coexist with completeness. The focus is on categorizing paradoxes, with special attention given to the group known as liar paradoxes, including Russell’s famous variation. The text demonstrates how these paradoxes are intrinsically linked to the principle of non-contradiction and argues that the truth and contradiction of propositions are both the cause and consequence of these paradoxes, presenting a dilemma within the system. The work introduces the concept of Aristotelian Sets (A-Sets) and Empty Sets as potential solutions to these paradoxes. It explores the idea that these sets, when carefully defined, can provide a meaningful representation of individual substances and predicates without violating the principle of non-contradiction. By proposing the inclusion of non-existents within a naive set theory and introducing A-Sets, this work seeks to contribute to the ongoing discourse surrounding paradoxes and their resolution. Ultimately, this study offers a fresh perspective on the handling of paradoxes, emphasizing the importance of reevaluating the foundations of formal and natural languages in the pursuit of a more comprehensive understanding of logic and philosophy.




Philosophy and Logic


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