liar.pdf

in A. Gupta and A. Chapuis (eds.), Circularity, Definition, and Truth, New Delhi, Indian Council of Philosophical Research, 2000

Notre Dame Journal of Formal Logic, 1977

The argument presented here purports to be a defense of material implication. The authors do not think that the argument is correct because, among other things, material implication does not seem to be in general equivalent to other types of ordinary-language ...

2019

History and Philosophy of Logic , 2021

In Formale Logik, published in 1956, J. M. Bocheński presented his first proposal for the solution to the liar paradox, which he related to Paul of Venice's argumentation from Logica Magna. A formalized version of this solution was then presented in Formalisierung einer scholastischen Lösung der Paradoxie des 'Lügners' in 1959. The historical references of the resulting formalism turn out to be closer to Albert de Saxon's argument and the later solution by John Buridan. Bocheński did not pose the question of the consistency of his theory. The case was taken up by B. Sobociński in his private letter to Bocheński from August 12, 1954. Sobociński used a smart translation of the language of Bocheński's theory into the classical propositional language with the notions of truth and falsehood inverted. The translation preserves the structure of the formalized solution. We explore Sobociński's idea and reconstruct his original proof.

Vivarium, 2002

Philosophical Studies

Tarski's hierarchical solution to the Liar paradox is widely viewed as ad hoc. In this paper I show that, on the contrary, Tarski's solution is justified by a sound philosophical principle that concerns the inner structure of truth. This principle provides a common philosophical basis to a number of solutions to the Liar paradox, including Tarski's and Kripke's. Tarski himself may not have been aware of this principle, but by providing a philosophical basis to his hierarchical solution to the paradox, it undermines the ad-hocness objection to this solution. Indeed, it contributes to the defense of Tarski's theory against other objections as well.

The True and the False Frege's basic distinction between sense and reference for singular terms (proper names and definite descriptions) is that the sense of a singular term contains a mode of presentation, whereas its reference is the object presented. Although each singular term has (or expresses) a sense, it does not necessarily refer to anything; senses are (or contain) manners of presentation, which may or may not present something. 1 After distinguishing sense and reference for singular terms, Frege raises the question whether there is a similar distinction for declarative sentences. 2 He states that a sentence contains a thought and argues that this thought cannot be the reference of the sentence, if any. The argument, based on the principle (R) The reference of a composite expression depends only on the reference of the parts and not on their sense, is essentially that whereas substitution of co-referential terms in a sentence would not change its reference (if any), it may change the thought contained in the sentence. 3 It is natural for Frege to argue thus, because one motivation for the distinction between sense and reference for singular terms is that the sentences (1) The morning star = the morning star, and (2) The morning star = the evening star, express different thoughts even though corresponding parts have the same reference. But in a way Frege's argument begs the question, because if sentences referred to thoughts, principle (R) would be false for sentences. For the argument to be conclusive Frege would need an independent justification for (R) that makes it plausible for reference in general.

Erkenntnis, 1994