The liar paradox is a famous and ancient paradox related to logic and philosophy. It shows it is perfectly possible to construct sentences that are correct grammatically and semantically but that cannot be true or false in the traditional sense. In this paper the authors show four approaches to interpreting paradoxes that illustrate the influence of: the levels of language, their belonging to indeterminate compatible propositions or indeterminate propositions, being based on universal antinomy and the theory of dialetheism.

This paper aims to describe and examine Alfred Tarski's famous semantic conception of truth as well as some of the critiques presented against it. The first part of this paper is divided into five segments: criteria imposed upon every adequate definition of truth are discussed in the first segment; the second is dedicated to Tarski’s Convention T; distinction between object language and metalanguage, as well as Tarski’s attitude toward formalized and colloquial languages, is described in the third segment; fourth segment (...) is devoted to Tarski’s definition of truth using the notion of “satisfaction”; the last segment is the evaluation of Tarski’s solution of paradoxes. In the second part of this paper the selected objections against Tarski’s conception are presented with emphasis on their diversity. (shrink)

In diesem Aufsatz wird ein neues Paradoxon vorgestellt, der Super-Lügner. Er ist stärker als alle bekannten Lügner-Sätze, nicht mehr eindeutig selbstreferentiell und läßt sich darüber hinaus in eindeutig in die Tarski-Hierarchie einordnen. Eine unendlich große Familie von Super-Lügnern auf Metaebenen ist konstruierbar. Schließlich widersetzt sich der Super-Lügner der Auflösung durch die neue vielversprechende Reflexionslogik LR von U. Blau.

In diesem Aufsatz wird ein neues Paradoxon vorgestellt, der Super-Lügner. Er ist stärker als alle bekannten Lügner-Sätze, nicht mehr eindeutig selbstreferentiell und läßt sich darüber hinaus in eindeutig in die Tarski-Hierarchie einordnen. Eine unendlich große Familie von Super-Lügnern auf Metaebenen ist konstruierbar. Schließlich widersetzt sich der Super-Lügner der Auflösung durch die neue vielversprechende Reflexionslogik LR von U. Blau.

This paper argues for tlie claims that a) a natural language such as English is semanticaly closed b) semantic closure implies inconsistency. A corollary of these is that the semantics of English must be paraconsistent. The first part of the paper formulates a definition of semantic closure which applies to natural languages and shows that this implies inconsistency. The second section argues that English is semeantically closed. The preceding discussion is predicated on the assumption that there are no truth value (...) gaps. The next section of the paper considers whether the possibility of these makes any difference to the substantive conclusions of the previous sections, and argues that it does not. The crux of the preceding arguments is that none of the consistent semantical accounts that have been offered for solving the semantical paradoxes is a semantic ofEnglish. The final section of the paper produces a general argument as to why this must always be the case. (shrink)

The Surprise Exam Paradox continues to perplex and torment despite the many solutions that have been offered. This paper proposes to end the intrigue once and for all by refuting one of the central pillars of the Surprise Exam Paradox, the 'No Friday Argument,' which concludes that an exam given on the last day of the testing period cannot be a surprise. This refutation consists of three arguments, all of which are borrowed from the literature: the 'Unprojectible Announcement Argument,' the (...) 'Wright & Sudbury Argument,' and the 'Epistemic Blindspot Argument.' The reason that the Surprise Exam Paradox has persisted this long is not because any of these arguments is problematic. On the contrary, each of them is correct. The reason that it has persisted so long is because each argument is only part of the solution. The correct solution requires all three of them to be combined together. Once they are, we may see exactly why the No Friday Argument fails and therefore why we have a solution to the Surprise Exam Paradox that should stick. (shrink)

The paper argues that the liar paradox teaches us these lessons about English. First, the paradox-yielding sentence is a sentence of English that is neither true nor false in English. Second, there is no English name for any such thing as a set of all and only true sentences of English. Third, ‘is true in English’ does not satisfy the axiom of comprehension.

In a series of papers R. L. Martin propounds a theory for dealing with the semantical paradoxes. This paper is a criticism of that theory.

Since universal language systems are confronted with serious paradoxical consequences, a semantic approach is developed in whichpartial worlds form the ontological basis. This approach shares withsituation semantics the basic idea that statements always refer to certain partial worlds, and it agrees with the extensional and model-theoretic character ofpossible worlds semantics. Within the framework of the partial worlds conception a satisfactory solution to theLiar paradox can be formulated. In particular, one advantage of this approach over those theories that are based on (...) the totality of possible worlds semantics can be found in the fact that the so-called Strengthened Liar problem is avoided. (shrink)

From the Editor’s Introduction: "The Internal Limitations of Human Understanding." We carry, unavoidably, the limits of our understanding with us. We are perpetually confined within the horizons of our conceptual structure. When this structure grows or expands, the breadth of our comprehensions enlarges, but we are forever barred from the wished-for glimpse beyond its boundaries, no matter how hard we try, no matter how much credence we invest in the substance of our learning and mist of speculation. -/- The limitations (...) in view here are not due to the mere finitude of our understanding of ourselves and of the world in which we live. They are limitations that come automatically and necessarily with any form of understanding. They are, as we shall see, part and parcel of any organization or ordering of data that we call information. -/- The consequences of these limitations are varied: As a result of them, hermeneutics cannot help but be hermetic; scientific theories of necessity are circumscribed by the boundaries of the ideas that define them; formal systems must choose between consistency and comprehensiveness; philosophical study, because it includes itself within its own proper subject matter, is forced to be reflexive in its self-enclosure. The fundamental dynamic shared by all forms of understanding testifies to an internal limitative keystone. (shrink)

A dialetheia is a sentence, A, such that both it and its negation, A, are true (we shall talk of sentences throughout this entry; but one could run the definition in terms of propositions, statements, or whatever one takes as her favourite truth bearer: this would make little difference in the context). Assuming the fairly uncontroversial view that falsity just is the truth of negation, it can equally be claimed that a dialetheia is a sentence which is both true and (...) false. (shrink)

A dialetheia is a sentence, A, such that both it and its negation, ¬A, are true (we shall talk of sentences throughout this entry; but one could run the definition in terms of propositions, statements, or whatever one takes as her favourite truth-bearer: this would make little difference in the context). Assuming the fairly uncontroversial view that falsity just is the truth of negation, it can equally be claimed that a dialetheia is a sentence which is both true and false.

I first discuss Chihara's claim that the presence of Liar-paradoxical sentences presents no problem for our understanding of natural languages, and argue that this cannot be held as easily as he suggests. I then consider the theories advanced by Martin, van Fraassen, Kripke and Burge which attempt to meet some of the problems involved. I argue that the claim in the first two theories that Liar sentences are ill-formed cannot be maintained, and that Burge's theory is methodologically unsound and seriously (...) incomplete. Kripke's theory, though it gives implausible truth-values to some sentences, is more satisfactory. Finally, I discuss Gupta's revision theory, and provide my own alternative which has the following advantages. First, it facilitates our understanding of Kripke's and Gupta's theories, and of their relationship. Second, it provides a third theory in which we can understand how the presence of the Liar does not radically infect a language. (shrink)