Volume 2, Issue 1 , Winter and Spring 2011, , Pages 1-23
Abstract
The current paper is an attempt to analyze the the Avicennian Cogent conditional quantifier based on Second-order Logic. Contemporary researchers have provided various formalizations of Avicennian conditionals to the Modern Logic language. A major difference between these formalizations is the analysis ...
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The current paper is an attempt to analyze the the Avicennian Cogent conditional quantifier based on Second-order Logic. Contemporary researchers have provided various formalizations of Avicennian conditionals to the Modern Logic language. A major difference between these formalizations is the analysis of conditional quantifier. In the most recent studies, Khajeh Nasir al-Din Toosi views about conditional quantifier, is used for analysis. His analysis of conditional quantifier can be formalized by Second-order Logic language. Therefore, some analyses are proposed to show using the Second-order Logic, the Avicennian cogent conditional finally could be formalized by Relevant Logic and Modal Logic. In this paper, it is shown this analysis is true assuming atemporal consequent and antecedent. Because of this assumption, the analysis has some difficulties. In order to solve this issue, we based the analysis on the assumption of temporal consequent and antecedent then analyzed the cogent conditional using Second-order Logic, Temporal Logic, Relevant Logic, and Modal Logic. The resulting formalization is a combination of Relevant Logic, Temporal Logic and Modal Logic.
Mojtaba Amirkhanlou
Volume 2, Issue 2 , Summer and Autumn 2011, , Pages 1-21
Abstract
In the present article, I try to study, analyze, and criticize some definitions of the concept of conceivability. In this relatively historical study, I have put particular importance on Descartes as the representative of definitions involving "conceiving". Then, I have discussed definitions involving ...
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In the present article, I try to study, analyze, and criticize some definitions of the concept of conceivability. In this relatively historical study, I have put particular importance on Descartes as the representative of definitions involving "conceiving". Then, I have discussed definitions involving "belief" and criticized them. After that, I have gone to definitions involving imaging (of a situation). In the conclusion, I have discussed definitions involving verification in the consistent, coherent, and possible worlds.
ali Akbar Ahmadi Afremjani; Ali Sadeghi Sadeghi
Volume 3, Issue 1 , Winter and Spring 2012, , Pages 1-25
Abstract
We in this article beside of explaining Quine’s most well-known criticisms of modal logic, try to show that Quine’s rejection of modal logic, and his opposition with essentialism, which he maintains that results from modal logic, could be founded on his epistemology and his treatment of objects. ...
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We in this article beside of explaining Quine’s most well-known criticisms of modal logic, try to show that Quine’s rejection of modal logic, and his opposition with essentialism, which he maintains that results from modal logic, could be founded on his epistemology and his treatment of objects. Meanwhile, we have mentioned Kripke’s point of view, as one of the most important defenders of modal logic. We are to show that Quine’s rejection of modal logic could be realized better if we consider it as opposing to Kripke’s ideas.
Zinat Ayatollahi
Volume 3, Issue 2 , Summer and Autumn 2012, , Pages 1-20
Abstract
This research examines the relation between logic and ethics and tries to investigate logically the corresponding dilemmas. Standard Deontic Logic which is initially appeared for studying ethical propositions cannot offer a suitable and accurate solution for conflict between duties. Therefore some new ...
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This research examines the relation between logic and ethics and tries to investigate logically the corresponding dilemmas. Standard Deontic Logic which is initially appeared for studying ethical propositions cannot offer a suitable and accurate solution for conflict between duties. Therefore some new deontic logics are made to represent this situation formally. For example Defeasible Deontic Logic and specially Reiter's Default Logic has a new approach to these moral dilemmas and offers an acceptable explanation of them.
Mahdi Assadi
Volume 4, Issue 1 , Winter and Spring 2013, , Pages 1-43
Abstract
The main purpose of this essay is to review and criticize the paper published earlier in this journal, Logical Study, titled ‘the Paradox of the informing from Absolute Unknown: Analyzing the Concept of information’ written by Sharifzadeh and Hodjati. In spite of having some useful points, ...
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The main purpose of this essay is to review and criticize the paper published earlier in this journal, Logical Study, titled ‘the Paradox of the informing from Absolute Unknown: Analyzing the Concept of information’ written by Sharifzadeh and Hodjati. In spite of having some useful points, the paper is, in several aspects, problematic. We review and criticize respectively such problematic points as: the expression of non-judgeability (ukmnāpadhīrī) in the absolute unknown (majhūl muṭlaq) debate; the invalidity of refer to Qaramaleki and Jahed in the criticism of the previous solutions; absolute non-existent division (ma‘dūm muṭlaq) into ontological and epistemological non-existent; the relationship between the absolute unknown and the absolute non-existent, and their solutions; neglecting the rule of far‘īyah and the predecessors’ strong definitions of the absolute non-existent; the solutions of the paper and its frequent inconsistencies; the successfulness of the paper in showing the indefensibility of the previous solutions; criticism of the analysis of the paper of ‘information’ (khabar) and probably of speech (sukhan); and misunderstanding the predecessors’ purpose; neglecting the definition of absolute unknown and the reason why it couldn’t be informed and spoken.
Hamed Bastin
Volume 4, Issue 2 , Summer and Autumn 2013, , Pages 1-17
Abstract
One of the crucial problems concerning Aristotle's modal logic is the incompatibility of his claims about the necessity and his teachings in the case of absolute syllogism. This problem has led to many controversies since Aristotle time, and most researchers have come to the conclusion that Aristotle’s ...
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One of the crucial problems concerning Aristotle's modal logic is the incompatibility of his claims about the necessity and his teachings in the case of absolute syllogism. This problem has led to many controversies since Aristotle time, and most researchers have come to the conclusion that Aristotle’s modal logic is contradictory. This article attempts through a new reading, which is as compatible as possible with Aristotle's claims, and based on his works and also his closer interpreters’ works such as Alexander of Aphrodisias, explains transferring necessity from a necessary premise to the conclusion and shows how Aristotle's viewpoint makes our argument possible and sound.
Mehdi Asadi
Volume 5, Issue 1 , Winter and Spring 2014, , Pages 1-30
Abstract
For Different thinkers, throughout history, ‘The unknowable non-existent’ has had different meanings. However, despite these differences, the ordinary absolute non-existent in Muslim philosophy (ma‘dūm muṭlaq; non-existent in both the external world and in the mind), can be ...
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For Different thinkers, throughout history, ‘The unknowable non-existent’ has had different meanings. However, despite these differences, the ordinary absolute non-existent in Muslim philosophy (ma‘dūm muṭlaq; non-existent in both the external world and in the mind), can be expressed in this way: absolute non-existent is never existed in external world or in mind (rather it is impossible to be conceived in the mind), neither detailedly nor un-detailedly, neither in perception nor in imagination and intellect. ‘The absolute non-existent’ leads us to a paradox which is usually called the paradox of informing from absolute non-existent; suppose that (P) is ‘The absolute nonexistent is unknowable’, since the very P is a kind of knowledge or information about the absolute nonexistent, so we are encountered to a paradox. In this paper I explore the roots of the ‘absolute nonexistent’ and the paradox in Greek philosophy; actually in Parmenides and Plato.
Mahdi Assadi
Volume 5, Issue 2 , Summer and Autumn 2014, , Pages 1-30
Abstract
external world and in the mind as well) paradox, so many solutions have been suggested: The difference in the intension and extension and its equivalent; the difference in the battī and lā–battī and its equivalent; and so forth. Having a glance at the incorrectness of these resolutions, the ...
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external world and in the mind as well) paradox, so many solutions have been suggested: The difference in the intension and extension and its equivalent; the difference in the battī and lā–battī and its equivalent; and so forth. Having a glance at the incorrectness of these resolutions, the essay shows the knowability of the absolute non–existent. Although here a few of thinkers previously have tried to show the knowability, we will show that their resolutions, due to not paying attention to the exact and strong definition of the unknowable and un-declarable absolute non–existent, are problematic. By summing up the different versions of the meaning in question, we will argue for the knowability of the absolute non–existent by means of four proofs: 1. the principle of non–contradiction; 2. non–existence qua non–existence; 3. the non–existentiality of the subject; 4. proof by reductio ad absurdum.
Meysam Mohammad Amini
Volume 6, Issue 1 , Winter and Spring 2015, , Pages 1-19
Abstract
In 1899, David Hilbert offers an articulated axiomatic system for Euclidean geometry and, demonstrating conditionally the meta-theorems of compatibility and independence for this system, proposes a solution to one of the enduring problems of mathematics (known as the problem of parallel lines). ...
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In 1899, David Hilbert offers an articulated axiomatic system for Euclidean geometry and, demonstrating conditionally the meta-theorems of compatibility and independence for this system, proposes a solution to one of the enduring problems of mathematics (known as the problem of parallel lines). Gottlob Frege, the founder of new formal logic, fundamentally disagreed with Hilbert’s formalistic approach and his proofs for the meta-theorems of compatibility and independence. The reasons for the opposition show that Frege's view on formality of logic and meta-theorems of compatibility and independence is very different from today's point of view. In this paper, after briefly discussing Hilbert’s method in demonstrating meta-theorems of compatibility and independence, and also the main Frege’s objections toward it, I will indicate to Frege’s own method dealing with these issues, and then discuss why eventually mathematicians and logicians, following Hilbert, ignored Frege’s remarks and modern logic, proposing a model theory, stepped on a road which was for Frege a wrong way.
Mahdi Assadi
Volume 6, Issue 2 , Summer and Autumn 2015, , Pages 1-36
Abstract
In Islamic logic and philosophy usually is said, as a rule, that the attribution of logical secondary inteligibles is totally subjective. This paper shows that sometimes some Muslim thinkers, in practice, have violated this rule unintentionally, in the discussion of absolute non–existent paradox, ...
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In Islamic logic and philosophy usually is said, as a rule, that the attribution of logical secondary inteligibles is totally subjective. This paper shows that sometimes some Muslim thinkers, in practice, have violated this rule unintentionally, in the discussion of absolute non–existent paradox, for example. We will reinforce this violation and will present stronger arguments for the external and objective attribution of at least some logical secondary intelligibles, i.e. matters that are tied with intentionality and signification such as ‘cognition’, ‘information’, ‘describility’, ‘non-describility’, ‘knowability’. In this way the generality of this rule is violated.
Traditional Logic
Davoud Heydari
Volume 7, Issue 1 , Summer and Autumn 2016, , Pages 1-29
Abstract
Some logicians earlier logicians, especially as long as the correlation provided or paid for. And even an independent treatises have been written on the subject. In contrast, others argue considered useless or less useful. Unfortunately, this issue has been raised in later works or abbreviated or omitted ...
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Some logicians earlier logicians, especially as long as the correlation provided or paid for. And even an independent treatises have been written on the subject. In contrast, others argue considered useless or less useful. Unfortunately, this issue has been raised in later works or abbreviated or omitted entirely. In many ways, provided the correlation is important in this debate as well as an understanding of the views of Muslim logicians was provided in the case and the arguments of the vote in comparison with the views of other ill-judged logicians. In this paper, counting and how to explain and prove they are connected Tlazmhay cases in the works presented logicians The review examines these issues, using the coding categories to see if there are other cases of correlation.
Philosophy of Language
Hamed Bastin; Seyyed Mohammad Ali Hodjati
Volume 7, Issue 2 , Summer and Autumn 2016, , Pages 1-28
Abstract
In answer to the Putnam problem about extensional non-determination of language terms, Millikan asks if this problem exists by a new definition of representation according to biological evidences, especially the principle of natural selection. The Millikan’s answer to this question is negative ...
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In answer to the Putnam problem about extensional non-determination of language terms, Millikan asks if this problem exists by a new definition of representation according to biological evidences, especially the principle of natural selection. The Millikan’s answer to this question is negative and she believes that the question should be changed to what is that feature, which turns a relation to representation-represented among numerous possible relations between words and objects? Her answer to this question is accorded to a hypothesis that is also the place of disputations and arguments in biology and has its supporters and opponents. Millikan is in the group, which has a historical view to the function and believes that the function of each entity must be defined regarding to what it supposed to do in its appearance history and dedicates the “proper” adjective to such function. The alternative hypothesis believes that the function must be defined regarding to what an entity do at the moment in equivalence to the current status. The key point of presenting the concept of “proper function” by Millikan is a redefinition of representation. In this article, we want to show that the new definition of representation is accorded to the concept of “Functure” as something completely objective, in opposed to the common view of philosophy to the representation, which take it as mental.
Philosophy of Logic
Volume 8, Issue 1 , Winter and Spring 2017, , Pages 1-13
Abstract
Cobreros et al. (2012) developed a theory of vagueness in order to model tolerance principles coherently, in the sense that not everything falls under a vague predicate and no sorites paradox is valid. It is argued in this paper that their characterization of tolerance principles does not match with ...
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Cobreros et al. (2012) developed a theory of vagueness in order to model tolerance principles coherently, in the sense that not everything falls under a vague predicate and no sorites paradox is valid. It is argued in this paper that their characterization of tolerance principles does not match with the standard conception of tolerance in the literature. In addition, their theory validates a stronger version of tolerance which suffers from clear counter examples. Furthermore, their theory validates tolerance just in a weak sense. That assimilates their theory with dominant theories of vagueness, those which accommodate tolerance principles not as true.
Philosophy of Logic
Nima Ahmadi; Lotfollah Nabavi; Seyyed Mohammad Ali Hodjati
Volume 8, Issue 2 , Summer and Autumn 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.
Masoud Alvand
Volume 9, Issue 1 , Summer and Autumn 2018, , Pages 1-17
Abstract
The incompatibility between the connectives of natural language and the language of classical logic in the truth-functionality has led some to think that the language of classical logic is incapable of representing the natural language sentences and formulating the arguments of this language. This paper ...
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The incompatibility between the connectives of natural language and the language of classical logic in the truth-functionality has led some to think that the language of classical logic is incapable of representing the natural language sentences and formulating the arguments of this language. This paper tries to show that the language of classical logic is not entirely incapable of that formulation, and the opposition's claim to the ability of the language of logic in representing the sentences and the arguments of the natural language is not complete. The defenses in this area are divided into two categories of direct and indirect defense. Although Grice's theory is a turning point for indirect defense, this paper deals with some of direct defense against defenders of the incompatibility of formalized arguments in the language of classical logic with natural language: first, with Strawson's arguments in opposition to the representation of natural language sentences by classical logic, we propound Clark's defense, and then we will see young's challenges against Clarke and Clarke's responses.
Mohammad Hafi; Mahin Bagheri; Mehdi Mirzapour; Gholamreza Zakiani
Volume 9, Issue 2 , Summer and Autumn 2018, , Pages 1-19
Abstract
The purpose of this research is to provide a new concept in Aristotelian categorical syllogism which is called groundability. A valid mood is called groundable if one would derive all the 24 valid moods in the Aristotelian’s syllogism by assuming only the valid mood and applying a chain of the ...
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The purpose of this research is to provide a new concept in Aristotelian categorical syllogism which is called groundability. A valid mood is called groundable if one would derive all the 24 valid moods in the Aristotelian’s syllogism by assuming only the valid mood and applying a chain of the following rules: simple conversion, reduction-ad-absurdum, sub-alternation, obversion and quantification negation. In this paper, we will prove that only the fifteen valid moods have the groundability property. Because Aristotle proves all the valid moods of other figures based on the four moods in the first figure, he considers these moods of the first figure as moods having the groundability property. We show that the groundability is not restricted to the first valid moods of the first figure--they are fifteen moods as stated. Thus, it can be shown that Aristotle's purpose from the self-evidence of the first figure is not the groundability of the four moods in the first figure. This important logical result in Aristotle's system is gained through the introducing the concept of the groundability of the moods in syllogism. We show that unlike the common view in the Aristotelian tradition, it is not the case that the groundability of the first figure must be the basis for explaining of being self-evidence of the four moods of the first figure. Regardless of what lies behind the evidence of the first figure valid moods, this paper will eliminate one of the options which is somehow a common wrong interpretation for answering the problem
Ruhollah Ebrahimpouresfahani; meghdad ghari
Abstract
Moore’s sentences are sentences of the form “p but I don't believe that p” or “p but I believe that not-p”. These sentences are called the omissive and the commissive form of Moorean sentence, respectively. These sentences might be true, yet they are ‘absurd’ ...
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Moore’s sentences are sentences of the form “p but I don't believe that p” or “p but I believe that not-p”. These sentences are called the omissive and the commissive form of Moorean sentence, respectively. These sentences might be true, yet they are ‘absurd’ to believe. It is usually claimed that absurdity only occurs when these sentences are formulated in the present tense, but if they are expressed in the past tenses or future tenses they would not be absurd. In this paper, we will analyze the Moore’s sentences in various tenses: past, present, and future. In this respect we employ a logic which is a combination of hybrid tense logic and doxastic logic. Then by formalizing the Moore’s sentences in various tenses we show that, contrary to popular belief, the past and future versions are not necessarily absurd. Finally, we give a necessary and sufficient condition for determining the absurdity of the Moore’s sentences
Hamidreza Badr
Abstract
Allameh Tabatabai, in the definition of predication , considers predication an existential union between the subject and the predicate. In this union, the subject is an existence by itself and the predicate is a connective existence (towards the subject). Then on the division of prediction, he divides ...
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Allameh Tabatabai, in the definition of predication , considers predication an existential union between the subject and the predicate. In this union, the subject is an existence by itself and the predicate is a connective existence (towards the subject). Then on the division of prediction, he divides prediction to 1. Primary and essential predication 2. Common technical predication 3. Realty and attenuate prediction. In the first predication, an essence predicates on itself, in the second predication, an accident predicates on an underlying subject. In third predication, a caused predicates on its cause. With a reflection on the topic of properties in analytical metaphysics and its relation to the philosophical foundations of Allameh Tabatabai, a serious conflict is established between the second predication and third predication. This conflict is resolved by providing a solution, but a second conflict arises. Finally, for the second conflict, the definition of predication must be changed. Therefore the “connective existence” must be changed to “relative existence”.
Davood Hosseini
Volume 1, Issue 1 , Winter and Spring 2010, , Pages 3-26
Abstract
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The present paper attempts to introduce vagueness and Sorites paradox. First, the observational adequacy of the issue and then its logical form are presented. Later on, the philosophical matters concerning the theoretical framework of vagueness and its philosophy are discussed. Finally, the present ...
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The present paper attempts to introduce vagueness and Sorites paradox. First, the observational adequacy of the issue and then its logical form are presented. Later on, the philosophical matters concerning the theoretical framework of vagueness and its philosophy are discussed. Finally, the present theories regarding vagueness are classified on the basis of various criteria and brief explanations are provided for each of them.
Ali Akbar Ahmadi Aframjani
Volume 1, Issue 2 , Summer and Autumn 2010, , Pages 3-15
Abstract
In this article we investigate the relation between two Hegel’s books “The Phenomenology of the Spirit [or Mind]” and “The Science of Logic”. We try to answer this question that which of these books is conceptually prior to and a basis for understanding the other? Does “The ...
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In this article we investigate the relation between two Hegel’s books “The Phenomenology of the Spirit [or Mind]” and “The Science of Logic”. We try to answer this question that which of these books is conceptually prior to and a basis for understanding the other? Does “The Phenomenology of the Spirit” makes clear Hegel’s claims in “The Science of Logic” or does the latter form a frame for understanding the former’s content? We will show that what has been appeared in Hegel’s writings confirms none of these choices. Moreover, accepting each of them has some implausible consequences.
Traditional Logic
Muhammad Tajik Joobeh; Muhammad Rasaffi
Abstract
Self-evident propositions as the foundation of Philosophy possess a significant position, but due to various reasons, they have been discussed only in margins. To explain the validity and inerrancy of these propositions, philosophers come up with different ideas. One of these Ideas was suggested by Misbah ...
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Self-evident propositions as the foundation of Philosophy possess a significant position, but due to various reasons, they have been discussed only in margins. To explain the validity and inerrancy of these propositions, philosophers come up with different ideas. One of these Ideas was suggested by Misbah Yazdi in which he refers them to immediate(presential) knowledge in order to benefit from the unerring feature of this kind of knowledge. Among all self-evident propositions in formal logic, he only considers the inner experience and prime knowledge(Awwaliyat) as two true and eligible instances of self-evident, because among all only these two meet the criteria of being self-evident, and because He believes that sensory knowledge is the source of the mistake, thus he tries to separate self-evident propositions from sensory perception and tie them up to immediate knowledge in order to guarantee the truth of these propositions. But this theory seems to have some errors, in this article we try to explain his theory and then elaborate on the features of immediate knowledge to discover some objections to this novel but apparently incomplete theory.
Philosophical Logic
Volume 8, Issue 1 , Winter and Spring 2017, , Pages 15-38
Abstract
Ali Wahidiyan Kamyad claimed in an article named “Methodology of Usage of Fuzzy Logic in Islamic View” that fuzzy logic is a part of the logic of sacred Quran. This claim was supported by a group of researchers, while it seems that the evidences to prove it are incomplete. So it seems necessary ...
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Ali Wahidiyan Kamyad claimed in an article named “Methodology of Usage of Fuzzy Logic in Islamic View” that fuzzy logic is a part of the logic of sacred Quran. This claim was supported by a group of researchers, while it seems that the evidences to prove it are incomplete. So it seems necessary to study the main claim again. What will be come at the continuing contains some critiques to this claim with respect to the Quranic evidences for which has been given. Besides some partial critiques to the correspondence of the Quranic examples which are claimed to be corresponded to the fuzzy argument given, it will be shown that there is a main fault in the claim that Quran has used in some verses the fuzzy logic which is based on a confusion of what is explicitly occurred in the passage as an argument (Mansus argument) and what is in ascribed to the passage by the reader (Mustanbat argument).
Mahnaz Amirkhani
Volume 1, Issue 2 , Summer and Autumn 2010, , Pages 17-32
Abstract
Opponent of the quantified modal logics believe that one of the most important objections to these logics is that they entail essentialism. Saul Kripke tries to overcome this challenge by showing that according to his first system, essentialism is acceptable without any inconsistency. In his revised ...
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Opponent of the quantified modal logics believe that one of the most important objections to these logics is that they entail essentialism. Saul Kripke tries to overcome this challenge by showing that according to his first system, essentialism is acceptable without any inconsistency. In his revised system, Kripke leaves, to some extent, his previous interpretation of essentialism and tries to propose a more plausible justification in defense of quantified modal logic. In addition to explaining the meaning of essentialism, this article gives a detailed explanation of Kripke’s debate in his first and revised systems.
Javad Beigi
Volume 4, Issue 2 , Summer and Autumn 2013, , Pages 18-41
Abstract
To have an applied attitude to Aristotelian logic it is necessary to understand deeply and correctly his syllogism and hence its figures. In this paper, we will discuss syllogism carefully in more details; one of the most important topics in syllogism is the valid and invalid moods, but the problem is ...
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To have an applied attitude to Aristotelian logic it is necessary to understand deeply and correctly his syllogism and hence its figures. In this paper, we will discuss syllogism carefully in more details; one of the most important topics in syllogism is the valid and invalid moods, but the problem is that thinkers have not paid so much attention to invalid and sterile moods as they have paid to valid moods. Here we give an equal importance to these two kinds of moods, and will indicate their practical role in the Aristotelian logic.
Mahin Bagheri; Mehdi Mirzapour; Gholamreza Zakiani
Volume 9, Issue 1 , Summer and Autumn 2018, , Pages 19-52
Abstract
Supposition theory is one of the most important logical- semantic theories which is put forward by medieval logicians in their logical texts and commentaries usually under the discussion topic "Properties of Terms". Since this theory has important consequences and results in logic, philosophy and theology, ...
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Supposition theory is one of the most important logical- semantic theories which is put forward by medieval logicians in their logical texts and commentaries usually under the discussion topic "Properties of Terms". Since this theory has important consequences and results in logic, philosophy and theology, in this paper we will investigate its conceptual and historical origin. We claim that there is a significant and deep (historical and conceptual) bound between the medieval theory of supposition and Aristotle’s theory of fallacies as he has stated in his treatise “sophistical refutations”. The case-by-base study of Aristotle’s fallacy in comparison to the semantical analysis of medieval logicians support this idea that supposition theory is the implicit semantic of Aristotle’s “sophistical refutations” which has been reinterpreted as an explicit and dependent field of study by medieval logicians, and also it has been extended throughout the late medieval ages due to different semantical problems.
