Search results for 'logical validity' (try it on Scholar)

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  1. Roy T. Cook (2014). There is No Paradox of Logical Validity. Logica Universalis 8 (3-4):447-467.score: 228.0
    A number of authors have argued that Peano Arithmetic supplemented with a logical validity predicate is inconsistent in much the same manner as is PA supplemented with an unrestricted truth predicate. In this paper I show that, on the contrary, there is no genuine paradox of logical validity—a completely general logical validity predicate can be coherently added to PA, and the resulting system is consistent. In addition, this observation lead to a number of novel, (...)
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  2. I. L. Janis & F. Frick (1943). The Relationship Between Attitudes Toward Conclusions and Errors in Judging Logical Validity of Syllogisms. Journal of Experimental Psychology 33 (1):73.score: 210.0
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  3. P. D. Welch (2011). Truth, Logical Validity and Determinateness: A Commentary on Field's Saving Truth From Paradox. Review of Symbolic Logic 4 (3):348-359.score: 182.0
    We consider notions of truth and logical validity defined in various recent constructions of Hartry Field. We try to explicate his notion of determinate truth by clarifying the path-dependent hierarchies of his determinateness operator.
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  4. Hartry Field (forthcoming). What Is Logical Validity? In Colin Caret & Ole Hjortland (eds.), Foundations of Logical Consequence.score: 180.0
    What are people who disagree about logic disagreeing about? The paper argues that (in a wide range of cases) they are primarily disagreeing about how to regulate their degrees of belief. An analogy is drawn between beliefs about validity and beliefs about chance: both sorts of belief serve primarily to regulate degrees of belief about other matters, but in both cases the concepts have a kind of objectivity nonetheless.
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  5. Stephan Körner (1979). On Logical Validity and Informal Appropriateness. Philosophy 54 (209):377 - 379.score: 150.0
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  6. Elton Mayo (1915). The Limits of Logical Validity. Mind 24 (93):70-74.score: 150.0
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  7. John L. Pollock (1967). Logical Validity in Modal Logic. The Monist 51 (1):128-135.score: 150.0
  8. Wolfgang Stegmüller (1964). Remarks on the Completeness of Logical Systems Relative to the Validity-Concepts of P. Lorenzen and K. Lorenz. Notre Dame Journal of Formal Logic 5 (2):81-112.score: 122.0
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  9. Gordon L. Brumm (1962). The Method of Possibility-Diagrams for Testing the Validity of Certain Types of Inferences, Based on Jevons' Logical Alphabet. Notre Dame Journal of Formal Logic 3 (4):209-233.score: 122.0
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  10. Christopher Gauker (2013). Logical Nihilism in Contemporary French Philosophy. Teorema 32 (2):65-79.score: 120.0
    Recanati takes for granted the conveyance conception of linguistic communica- tion, although it is not very clear exactly where he lies on the spectrum of possible variations. Even if we disavow all such conceptions of linguistic communication, there will be a place for semantic theory in articulating normative concepts such as logical consistency and logical validity. An approach to semantics focused on such normative concepts is illustrated using the example of ““It’’s raining””. It is argued that Recanati’’s (...)
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  11. J. P. Cleave (1970). The Notion of Validity in Logical Systems with Inexact Predicates. British Journal for the Philosophy of Science 21 (3):269-274.score: 120.0
  12. Stefan Nowak (1978). Logical and Empirical Assumptions of Validity of Inductions. Synthese 37 (3):321 - 349.score: 120.0
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  13. Stephan Leuenberger (2013). De Jure and De Facto Validity in the Logic of Time and Modality. Thought: A Journal of Philosophy 2 (2):196-205.score: 118.0
    What formulas are tense-logically valid depends on the structure of time, for example on whether it has a beginning. Logicians have investigated what formulas correspond to what physical hypotheses about time. Analogously, we can investigate what formulas of modal logic correspond to what metaphysical hypotheses about necessity. It is widely held that physical hypotheses about time may be contingent. If so, tense-logical validity may be contingent. In contrast, validity in modal logic is typically taken to be non-contingent, (...)
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  14. Michael Baumgartner (2013). Exhibiting Interpretational and Representational Validity. Synthese:1-25.score: 114.0
    A natural language argument may be valid in at least two nonequivalent senses: it may be interpretationally or representationally valid (Etchemendy in The concept of logical consequence. Harvard University Press, Cambridge, 1990). Interpretational and representational validity can both be formally exhibited by classical first-order logic. However, as these two notions of informal validity differ extensionally and first-order logic fixes one determinate extension for the notion of formal validity (or consequence), some arguments must be formalized by unrelated (...)
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  15. Mario Gómez-Torrente (2000). A Note on Formality and Logical Consequence. Journal of Philosophical Logic 29 (5):529-539.score: 106.0
    Logic is formal in the sense that all arguments of the same form as logically valid arguments are also logically valid and hence truth-preserving. However, it is not known whether all arguments that are valid in the usual model-theoretic sense are truthpreserving. Tarski claimed that it could be proved that all arguments that are valid (in the sense of validity he contemplated in his 1936 paper on logical consequence) are truthpreserving. But he did not offer the proof. The (...)
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  16. William H. Hanson (2006). Actuality, Necessity, and Logical Truth. Philosophical Studies 130 (3):437 - 459.score: 102.0
    The traditional view that all logical truths are metaphysically necessary has come under attack in recent years. The contrary claim is prominent in David Kaplan’s work on demonstratives, and Edward Zalta has argued that logical truths that are not necessary appear in modal languages supplemented only with some device for making reference to the actual world (and thus independently of whether demonstratives like ‘I’, ‘here’, and ‘now’ are present). If this latter claim can be sustained, it strikes close (...)
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  17. William H. Hanson (2014). Logical Truth in Modal Languages: Reply to Nelson and Zalta. [REVIEW] Philosophical Studies 167 (2):327-339.score: 102.0
    Does general validity or real world validity better represent the intuitive notion of logical truth for sentential modal languages with an actuality connective? In (Philosophical Studies 130:436–459, 2006) I argued in favor of general validity, and I criticized the arguments of Zalta (Journal of Philosophy 85:57–74, 1988) for real world validity. But in Nelson and Zalta (Philosophical Studies 157:153–162, 2012) Michael Nelson and Edward Zalta criticize my arguments and claim to have established the superiority of (...)
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  18. Charlie Kurth (2011). Logic for Morals, Morals From Logic. Philosophical Studies 155 (2):161-180.score: 94.0
    The need to distinguish between logical and extra-logical varieties of inference, entailment, validity, and consistency has played a prominent role in meta-ethical debates between expressivists and descriptivists. But, to date, the importance that matters of logical form play in these distinctions has been overlooked. That’s a mistake given the foundational place that logical form plays in our understanding of the difference between the logical and the extra-logical. This essay argues that descriptivists are better (...)
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  19. Christopher Gauker (1990). Semantics Without Reference. Notre Dame Journal of Formal Logic 31 (3):437-461.score: 92.0
    A theory of reference may be either an analysis of reference or merely an account of the correct use of the verb "refer". If we define the validity of arguments in the standard way, in terms of assignments of individuals and sets to the nonlogical vocabulary of the language, then we will be committed to seeking an analysis of reference. Those who prefer a metalinguistic account, therefore, will desire an alternative to standard semantics. One alternative is the Quinean conception (...)
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  20. Peter Pagin (2012). Assertion, Inference, and Consequence. Synthese 187 (3):869 - 885.score: 90.0
    In this paper the informativeness account of assertion (Pagin in Assertion. Oxford University Press, Oxford, 2011) is extended to account for inference. I characterize the conclusion of an inference as asserted conditionally on the assertion of the premises. This gives a notion of conditional assertion (distinct from the standard notion related to the affirmation of conditionals). Validity and logical validity of an inference is characterized in terms of the application of method that preserves informativeness, and contrasted with (...)
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  21. Christopher Gauker (2014). How Many Bare Demonstratives Are There in English? Linguistics and Philosophy 37 (4):291-314.score: 90.0
    In order to capture our intuitions about the logical consistency of sentences and the logical validity of arguments, a semantics for a natural language has to allow for the fact that different occurrences of a single bare demonstrative, such as “this”, may refer to different objects. But it is not obvious how to formulate a semantic theory in order to achieve this result. This paper first criticizes several proposals: that we should formulate our semantics as a semantics (...)
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  22. Pablo Cobreros (2011). Varzi on Supervaluationism and Logical Consequence. Mind 120 (479):833-43.score: 84.0
    Though it is standardly assumed that supervaluationism applied to vagueness is committed to global validity, Achille Varzi (2007) argues that the supervaluationist should take seriously the idea of adopting local validity instead. Varzi’s motivation for the adoption of local validity is largely based on two objections against the global notion: that it brings some counterexamples to classically valid rules of inference and that it is inconsistent with unrestricted higher-order vagueness. In this discussion I review these objections and (...)
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  23. Richard B. Angell (2001). The 'Most Important and Fundamental' Distinction in Logic. Informal Logic 21 (1).score: 84.0
    Personal reflections on the philosophical career of Henry Johnstone, B.S. Haverford College, 1942, and Ph.D. Harvard, 1950, professor at Williams College 1948-1952 and Pennsylvania State University, 1952 - 2000. Founder and editor of Philosophy and Rhetoric, Johnstone wrote eight books, including two logic texts, three monographs, and over 150 articles or reviews. The focus is on his efforts to resolve problems stemming from the conflict between the logical empiricism Johnstone embraced in his dissertation, and the arguments of his absolute (...)
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  24. Author unknown, Validity and Soundness. Internet Encyclopedia of Philosophy.score: 78.0
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  25. Mark T. Nelson (1995). Is It Always Fallacious to Derive Values From Facts? Argumentation 9 (4):553-562.score: 74.0
    Charles Pigden has argued for a logical Is/Ought gap on the grounds of the conservativeness of logic. I offer a counter-example which shows that Pigden’s argument is unsound and that there need be no logical gap between Is-premises and an Ought-conclusion. My counter-example is an argument which is logically valid, has only Is-premises and an Ought-conclusion, does not purport to violate the conservativeness of logic, and does not rely on controversial assumptions about Aristotelian biology or 'institutional facts.'.
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  26. Julien Murzi (2014). The Inexpressibility of Validity. Analysis 74 (1):65-81.score: 72.0
    Tarski's Undefinability of Truth Theorem comes in two versions: that no consistent theory which interprets Robinson's Arithmetic (Q) can prove all instances of the T-Scheme and hence define truth; and that no such theory, if sound, can even express truth. In this note, I prove corresponding limitative results for validity. While Peano Arithmetic already has the resources to define a predicate expressing logical validity, as Jeff Ketland has recently pointed out (2012, Validity as a primitive. Analysis (...)
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  27. Gil Sagi (forthcoming). Formality in Logic: From Logical Terms to Semantic Constraints. Logique Et Analyse.score: 72.0
    In the paper I discuss a prevailing view by which logical terms determine forms of sentences and arguments and therefore the logical validity of arguments. This view is common to those who hold that there is a principled distinction between logical and nonlogical terms and those holding relativistic accounts. I adopt the Tarskian tradition by which logical validity is determined by form, but reject the centrality of logical terms. I propose an alternative framework (...)
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  28. Yukio Iwakuma (1987). Instantiae: An Introduction to a Twelfth Century Technique of Argumentation. [REVIEW] Argumentation 1 (4):437-453.score: 72.0
    An instantia is a technique to refute other's arguments, found in many tracts from the latter half of the twelfth century. An instantia has (or appears to have) the same form as the argument to be refuted and its falsity is more evident than that of the argument.Precursors of instantiae are among the teachings of masters active in the first half of the century. These masters produce counter-arguments against various inferential forms in order to examine their validity. But the (...)
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  29. Edgar Andrade-Lotero & Catarina Dutilh Novaes (2012). Validity, the Squeezing Argument and Alternative Semantic Systems: The Case of Aristotelian Syllogistic. [REVIEW] Journal of Philosophical Logic 41 (2):387-418.score: 68.0
    We investigate the philosophical significance of the existence of different semantic systems with respect to which a given deductive system is sound and complete. Our case study will be Corcoran’s deductive system D for Aristotelian syllogistic and some of the different semantic systems for syllogistic that have been proposed in the literature. We shall prove that they are not equivalent, in spite of D being sound and complete with respect to each of them. Beyond the specific case of syllogistic, the (...)
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  30. Edgar Andrade-Lotero & Catarina Dutilh Novaes (2012). Validity, the Squeezing Argument and Alternative Semantic Systems: The Case of Aristotelian Syllogistic. [REVIEW] Journal of Philosophical Logic 41 (2):387 - 418.score: 68.0
    We investigate the philosophical significance of the existence of different semantic systems with respect to which a given deductive system is sound and complete. Our case study will be Corcoran's deductive system D for Aristotelian syllogistic and some of the different semantic systems for syllogistic that have been proposed in the literature. We shall prove that they are not equivalent, in spite of D being sound and complete with respect to each of them. Beyond the specific case of syllogistic, the (...)
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  31. Phil Corkum, Aristotle on Logical Consequence.score: 66.0
    Compare two conceptions of validity: under an example of a modal conception, an argument is valid just in case it is impossible for the premises to be true and the conclusion false; under an example of a topic-neutral conception, an argument is valid just in case there are no arguments of the same logical form with true premises and a false conclusion. This taxonomy of positions suggests a project in the philosophy of logic: the reductive analysis of the (...)
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  32. Mark T. Nelson (2007). More Bad News for the Logical Autonomy of Ethics. Canadian Journal of Philosophy 37 (2):203-216.score: 66.0
    Are there good arguments from Is to Ought? Toomas Karmo has claimed that there are trivially valid arguments from Is to Ought, but no sound ones. I call into question some key elements of Karmo’s argument for the “logical autonomy of ethics”, and show that attempts to use it as part of an overall case for moral skepticism would be self-defeating.
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  33. Gillian Russell (2008). One True Logic? Journal of Philosophical Logic 37 (6):593 - 611.score: 66.0
    This is a paper about the constituents of arguments. It argues that several different kinds of truth-bearer may be taken to compose arguments, but that none of the obvious candidates—sentences, propositions, sentence/truth-value pairs etc.—make sense of logic as it is actually practiced. The paper goes on to argue that by answering the question in different ways, we can generate different logics, thus ensuring a kind of logical pluralism that is different from that of J. Beall and Greg Restall.
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  34. Matthew William McKeon (2009). A Plea for Logical Objects. Synthese 167 (1):163 - 182.score: 66.0
    An account of validity that makes what is invalid conditional on how many individuals there are is what I call a conditional account of validity. Here I defend conditional accounts against a criticism derived from Etchemendy’s well-known criticism of the model-theoretic analysis of validity. The criticism is essentially that knowledge of the size of the universe is non-logical and so by making knowledge of the extension of validity depend on knowledge of how many individuals there (...)
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  35. Arnon Avron, Furio Honsell, Marino Miculan & Cristian Paravano (1998). Encoding Modal Logics in Logical Frameworks. Studia Logica 60 (1):161-208.score: 66.0
    We present and discuss various formalizations of Modal Logics in Logical Frameworks based on Type Theories. We consider both Hilbert- and Natural Deduction-style proof systems for representing both truth (local) and validity (global) consequence relations for various Modal Logics. We introduce several techniques for encoding the structural peculiarities of necessitation rules, in the typed -calculus metalanguage of the Logical Frameworks. These formalizations yield readily proof-editors for Modal Logics when implemented in Proof Development Environments, such as Coq or (...)
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  36. Dag Prawitz (2012). The Epistemic Significance of Valid Inference. Synthese 187 (3):887-898.score: 64.0
    The traditional picture of logic takes it for granted that "valid arguments have a fundamental epistemic significance", but neither model theory nor traditional proof theory dealing with formal system has been able to give an account of this significance. Since valid arguments as usually understood do not in general have any epistemic significance, the problem is to explain how and why we can nevertheless use them sometimes to acquire knowledge. It is suggested that we should distinguish between arguments and acts (...)
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  37. Susanne Bobzien (1999). Logic: The Stoics (Part One). In Keimpe Algra & et al (eds.), The Cambridge History of Hellenistic Philosophy. Cambridge University Press.score: 62.0
    ABSTRACT: A detailed presentation of Stoic logic, part one, including their theories of propositions (or assertibles, Greek: axiomata), demonstratives, temporal truth, simple propositions, non-simple propositions(conjunction, disjunction, conditional), quantified propositions, logical truths, modal logic, and general theory of arguments (including definition, validity, soundness, classification of invalid arguments).
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  38. Uwe Meixner (1995). Ontologically Minimal Logical Semantics. Notre Dame Journal of Formal Logic 36 (2):279-298.score: 62.0
    Ontologically minimal truth law semantics are provided for various branches of formal logic (classical propositional logic, S5 modal propositional logic, intuitionistic propositional logic, classical elementary predicate logic, free logic, and elementary arithmetic). For all of them logical validity/truth is defined in an ontologically minimal way, that is, not via truth value assignments or interpretations. Semantical soundness and completeness are proved (in an ontologically minimal way) for a calculus of classical elementary predicate logic.
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  39. Eli Dresner (2010). Logical Consequence and First-Order Soundness and Completeness: A Bottom Up Approach. Notre Dame Journal of Formal Logic 52 (1):75-93.score: 60.0
    What is the philosophical significance of the soundness and completeness theorems for first-order logic? In the first section of this paper I raise this question, which is closely tied to current debate over the nature of logical consequence. Following many contemporary authors' dissatisfaction with the view that these theorems ground deductive validity in model-theoretic validity, I turn to measurement theory as a source for an alternative view. For this purpose I present in the second section several of (...)
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  40. Paul Weingartner (2011). God's Existence: Can It Be Proven? A Logical Commentary on the Five Ways of Thomas Aquinas. European Journal for Philosophy of Religion 3 (1):243 - 248.score: 60.0
    The aim of the book is to show that the ’five ways’ of Thomas Aquinas, i.e., his five arguments to prove the existence of God, are logically correct arguments by the standards of modern predicate logic. In the first chapter this is done by commenting on the two preliminary articles preceding the five ways in which Thomas Aquinas points out that on the one hand the existence of God is not self-evident to us and on the other hand, that, similar (...)
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  41. Pablo Cobreros (2011). Supervaluationism and Classical Logic. In Rick Nouwen, Robert van Rooij, Hans-Christian Schmitz & Uli Sauerland (eds.), Vagueness in Communication, Lecture Notes in Computer Science, Vol. 6517. Springer.score: 58.0
    This paper is concerned with the claim that supervaluationist consequence is not classical for a language including an operator for definiteness. Although there is some sense in which this claim is uncontroversial, there is a sense in which the claim must be qualified. In particular I defend Keefe's position according to which supervaluationism is classical except when the inference from phi to Dphi is involved. The paper provides a precise content to this claim showing that we might provide complete (and (...)
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  42. Georg Spielthenner (2007). A Logic of Practical Reasoning. Acta Analytica 22 (2):139-153.score: 58.0
    In this paper my primary aim is to present a logical system of practical reasoning that can be used to assess the validity of practical arguments, that is, arguments with a practical judgment as conclusion. I begin with a critical evaluation of other approaches to this issue and argue that they are inadequate. On the basis of these considerations, I explain in Sect. 2 the informal conception of practical validity and introduce in Sect. 3 the logical (...)
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  43. Jonathan Lear (1980). Aristotle and Logical Theory. Cambridge University Press.score: 58.0
    Aristotle was the first and one of the greatest logicians. He not only devised the first system of formal logic, but also raised many fundamental problems in the philosophy of logic. In this book, Dr Lear shows how Aristotle's discussion of logical consequence, validity and proof can contribute to contemporary dabates in the philosophy of logic. No background knowledge of Aristotle is assumed.
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  44. Keith Stenning & Michiel Lambalgen (2004). A Little Logic Goes a Long Way: Basing Experiment on Semantic Theory in the Cognitive Science of Conditional Reasoning. Cognitive Science 28 (4):481-529.score: 58.0
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  45. Hartry Field (forthcoming). Disarming a Paradox of Validity. Notre Dame Journal of Formal Logic.score: 56.0
    Abstract. Any theory of truth must find a way around Curry’s paradox, and there are well-known ways to do so. This paper concerns an apparently analogous paradox, about validity rather than truth, which JC Beall and Julien Murzi (“Two Flavor's of Curry's Paradox”) call the v-Curry. They argue that there are reasons to want a common solution to it and the standard Curry paradox, and that this rules out the solutions to the latter offered by most “naive truth theorists”. (...)
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  46. Robert Hanna (2008). Husserl's Arguments Against Logical Psychologism (Prolegomena, §§ 17–61). In Verena Mayer (ed.), Edmund Husserl: Logische Untersuchungen. 27-42.score: 56.0
    According to Edmund Husserl in the Prolegomena to Pure Logic,<span class='Hi'></span> which constitutes the preliminary rational foundation for <span class='Hi'></span>– and also the entire first volume of <span class='Hi'></span>– his Logical Investigations,<span class='Hi'></span> pure logic is the a priori theoretical,<span class='Hi'></span> nomological science of <span class='Hi'></span>„demonstration“<span class='Hi'></span> (LI 1,<span class='Hi'></span> 57;<span class='Hi'></span> Hua XVIII,<span class='Hi'></span> 23)<span class='Hi'></span>.1 For him,<span class='Hi'></span> demonstration includes both consequence and provability.<span class='Hi'></span> Consequence is the defining property of all and only formally valid arguments,<span class='Hi'></span> (...)
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  47. Timothy McCarthy (1987). Modality, Invariance, and Logical Truth. Journal of Philosophical Logic 16 (4):423 - 443.score: 56.0
    Let us sum up. We began with the question, “What is the interest of a model-theoretic definition of validity?” Model theoretic validity consists in truth under all reinterpretations of non-logical constants. In this paper, we have described for each necessity concept a corresponding modal invariance property. Exemplification of that property by the logical constants of a language leads to an explanation of the necessity, in the corresponding sense, of its valid sentences. I have fixed upon the (...)
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  48. Jose Saguillo (2009). Methodological Practice and Complementary Concepts of Logical Consequence: Tarski's Model-Theoretic Consequence and Corcoran's Information-Theoretic Consequence. History and Philosophy of Logic 30 (1):21-48.score: 56.0
    This article discusses two coextensive concepts of logical consequence that are implicit in the two fundamental logical practices of establishing validity and invalidity for premise-conclusion arguments. The premises and conclusion of an argument have information content (they ?say? something), and they have subject matter (they are ?about? something). The asymmetry between establishing validity and establishing invalidity has long been noted: validity is established through an information-processing procedure exhibiting a step-by-step deduction of the conclusion from the (...)
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  49. Luis M. Laita (1980). Boolean Algebra and its Extra-Logical Sources: The Testimony of Mary Everest Boole. History and Philosophy of Logic 1 (1-2):37-60.score: 56.0
    Mary Everest, Boole's wife, claimed after the death of her husband that his logic had a psychological, pedagogical, and religious origin and aim rather than the mathematico-logical ones assigned to it by critics and scientists. It is the purpose of this paper to examine the validity of such a claim. The first section consists of an exposition of the claim without discussing its truthfulness; the discussion is left for the sections 2?4, in which some arguments provided by the (...)
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  50. Max A. Freund (1996). Semantics for Two Second-Order Logical Systems: $\Equiv$ RRC* and Cocchiarella's RRC. Notre Dame Journal of Formal Logic 37 (3):483-505.score: 56.0
    We develop a set-theoretic semantics for Cocchiarella's second-order logical system . Such a semantics is a modification of the nonstandard sort of second-order semantics described, firstly, by Simms and later extended by Cocchiarella. We formulate a new second order logical system and prove its relative consistency. We call such a system and construct its set-theoretic semantics. Finally, we prove completeness theorems for proper normal extensions of the two systems with respect to certain notions of validity provided by (...)
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