Philosophy of Logic
Siavash Ahmadzadeh; Lotfollah Nabavi
Abstract
Naïve truth, T(x), is a predicate that applies to all of the sentences of the language and also for every sentence A of the language, T(˹A˺)↔A holds. Tarski for avoiding the liar paradox and trivializing of the language (theory) forced to withdraw from defining the naïve notion of truth ...
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Naïve truth, T(x), is a predicate that applies to all of the sentences of the language and also for every sentence A of the language, T(˹A˺)↔A holds. Tarski for avoiding the liar paradox and trivializing of the language (theory) forced to withdraw from defining the naïve notion of truth and he defined truth of every language in a metalanguage. Proponents of paraconsistency claim that by accepting paraconsistent logics we can retain the naïve truth predicate. A logic would be called paraconsistent if contradiction does not entail everything. But there is another paradox, the Curry paradox, which is related to conditionals and without using EFQ can trivialize naïve theories of truth. In this paper I will argue that although if we add arithmetic and naïve truth predicate to paraconsistent logics we would have a non-trivial theory, but for low deductive power, losing some prospected properties of naïve truth predicate and leaking of inconsistency to pure arithmetic parts, these logics will be unjustifiable.
Seyyed Mohammad Ali Hodjati; Hassan Hamtaii; Lotfollah Nabavi
Abstract
According to Priest’s Modal Meinongianism, every condition expressible in language, characterizes some object(s) satisfying the very condition, either in the actual world or in some other world(s). Similar commitments of other Meinongians, to such an unrestricted principle of characterization (CP), ...
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According to Priest’s Modal Meinongianism, every condition expressible in language, characterizes some object(s) satisfying the very condition, either in the actual world or in some other world(s). Similar commitments of other Meinongians, to such an unrestricted principle of characterization (CP), provokes the emergence of the Clark paradox. We argue that the inter-world bleed of information within Priest’s system of logic may ground similar complications. We demonstrate how to secure the possibility of world-shift by employing internal resources of the noneist semantics. This results in triviality; far beyond contradiction. Priest has to put restrictions on the CP.According to Priest’s Modal Meinongianism, every condition expressible in language, characterizes some object(s) satisfying the very condition, either in the actual world or in some other world(s). Similar commitments of other Meinongians, to such an unrestricted principle of characterization (CP), provokes the emergence of the Clark paradox. We argue that the inter-world bleed of information within Priest’s system of logic may ground similar complications. We demonstrate how to secure the possibility of world-shift by employing internal resources of the noneist semantics. This results in triviality; far beyond contradiction. Priest has to put restrictions on the CP.
Hassan Hamtaii; Seyyed Mohammad Ali Hodjati; Lotfollah Nabavi
Abstract
The Unity of the Encoding PropositionAbstract: There is a family of problems under the rubric of “the unity of the proposition”. They ask how is it that (ordinary) propositions are unit wholes over and above their constituting parts, how is it that they are representational and have truth values. ...
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The Unity of the Encoding PropositionAbstract: There is a family of problems under the rubric of “the unity of the proposition”. They ask how is it that (ordinary) propositions are unit wholes over and above their constituting parts, how is it that they are representational and have truth values. In this paper, we propose the very same concern regarding the Meinongian encoding propositions; those propositions that contain the encoding mode of predication rather than the ordinary exemplificational predication. Embracing such a dual mode of predication lets us interpret propositions such as “the round square is round” not only as meaningful but also as true propositions. We demonstrate how to reduce exemplification to encoding. This should dissolve the classical problem of the propositional unity, yet providing a rather new formulation of it.
Amer Amikhteh; Lotfollah Nabavi
Abstract
The uninorm logic UL is a fuzzy, substructural and semi-relevant logic. The Gentzen-style system for UL is obtained by removing the contraction rules and weakening from the Gentzen-style system of Godel fuzzy logic. The UL lacks "excluded middle", "positive paradox" and "negative paradox". The truth ...
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The uninorm logic UL is a fuzzy, substructural and semi-relevant logic. The Gentzen-style system for UL is obtained by removing the contraction rules and weakening from the Gentzen-style system of Godel fuzzy logic. The UL lacks "excluded middle", "positive paradox" and "negative paradox". The truth function of uninorm is a relevance weakening of the t-norm function. In this article, we introduce the new logic ULΔ. ULΔ is obtained by adding Δ to UL. ULΔ, an expansion of classical logic, is a normal semilinear modal logic; i.e. it is strongly sound and complete w.r.t. a linearly ordered algebra. And with the theorem of (p→q)∨Δ(q→p) it is distinguished from other standard systems of modal logic. Δφ is intuitively interpreted as "true that φ" or more precisely "classically true that φ". In this paper, we introduce the semi-classical logic ULΔ with four approaches, axiomatizations, hypersequent calculi, algebraic semantics and standard semantics. metatheorems we are considering include Delta deduction, strong soundness, strong standard completeness and definability of classical logic.
Mohsen Shabani Samghabadi; Lotfollah Nabavi; Seyyed Mohammad Ali Hodjati
Philosophy of Logic
Nima Ahmadi; Lotfollah Nabavi; Seyyed Mohammad Ali Hodjati
Volume 8, Issue 2 , November 2017, , Pages 1-23
Abstract
Contextualism is the main opponent of minimalism. The debate between these two semantical approaches, stem in an old fashion dispute to determine the border between semantics and pragmatics. Contextualists claim that the sentences in the natural language are not truth-evaluable before being enriched ...
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Contextualism is the main opponent of minimalism. The debate between these two semantical approaches, stem in an old fashion dispute to determine the border between semantics and pragmatics. Contextualists claim that the sentences in the natural language are not truth-evaluable before being enriched pragmatically. In contrast, in minimalists’ viewpoint, there is a minimal semantic content that provides the truth-evaluable meaning of sentences in a way that context of utterance has limited effects on it. This contrast is based on the way and extent to which context affects semantic content. In this paper, after introducing these two approaches, the main arguments of contextualists against minimalist are discussed, then we show that minimalistic semantics like Kaplan's LD with objective interpretation of context cannot present any proper model even for sentences containing first-person reference, and on the basis of a subjective interpretation of context, the indexical/non-indexical distinction is not clear and other expressions of natural languages can be indexical, in a broad sense.
Seied Mohammad Ali Hodjati; Homan Mohammad Ghorbanian; Lotfollah Nabavi; Arsalan Golfam
Volume 4, Issue 1 , March 2013, , Pages 44-64
Abstract
Many philosophers claim that semantic content of language is normative, which means that meaning of a term prescribes the pattern of use or determines which pattern of use can be described as ‘correct’. The most important arguments for normativity, made by Kripke, Boghossian and others, are ...
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Many philosophers claim that semantic content of language is normative, which means that meaning of a term prescribes the pattern of use or determines which pattern of use can be described as ‘correct’. The most important arguments for normativity, made by Kripke, Boghossian and others, are based on the concepts of ‘regularities’, ‘correct uses’ and ‘possibility of semantic mistakes’. But some philosophers have scrutinized the slogan ‘meaning is normative’ and have found some flaws in pro arguments. There are good reasons to consider the normativity of meaning as a side effect of ‘being public ’; that is, meaning, as itself, is neutral to correct or incorrect uses, but the moral or social laws of society impose several norms on language.
Lotfollah Nabavi; Amirhossein Yaraghchi
Volume 3, Issue 2 , September 2012, , Pages 83-103
Abstract
From the very beginning up to now the concept of existence has been one of the most controversial ones among the philosophers. Such discussions can be divided into two main parts. The first one refers to the ontological aspects of existence for which one is involved with two schools namely Possibilism ...
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From the very beginning up to now the concept of existence has been one of the most controversial ones among the philosophers. Such discussions can be divided into two main parts. The first one refers to the ontological aspects of existence for which one is involved with two schools namely Possibilism and Actualism anyone of which tries to talk of the scope and limit of things within their own metaphysical principles. The second part includes the issues about existence as a predicate. For these discussions and because we want to consider existence as a first or a second order predicate, we can either talk about the possible existence or its counterpart i.e., the necessary existence of the things. The necessary existence is one of the formula which, in the simplest quantified modal logic of S5 and just like those formula such as BF and CBF, is provable and valid. Although talking of the validity of necessary existence things needs to provide a second degree concept of existence but discussing the validity of Barcan formula needs an existential commitment to the possible things which the possibilists believe are not among the existent things. Following Linsky and Zalta and for defending BF and NE formula, Timotty Williamson has excluded the validity issue of Barcan formula from the first part and he has transferred it to the second part. Thus using the modal properties he provides a new definition of possible things through which one can defend the validity of Barcan formula as well as the necessary existence of things without having any existential commitment to the possibilia. Afterwards, Williamson provides the conditions for talking of the logical existence for things by providing a second-order concept of existence in unrestricted quantification theory and in this way one can have a better understanding of necessary existence.
