Semantic and Mathematical Foundations for Intuitionism
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NSP4 Pragmatist Kant
Nordic NSP Studies in Pragmatism Helsinki — 2019 Giovanni Maddalena “Anti-Kantianism as a Necessary Characteristic of Pragmatism” In: Krzysztof Piotr Skowronski´ and Sami Pihlstrom¨ (Eds.) (2019). Pragmatist Kant—Pragmatism, Kant, and Kantianism in the Twenty-first Century (pp. 43–59). Nordic Studies in Pragmatism 4. Helsinki: Nordic Pragmatism Network. issn-l 1799-3954 issn 1799-3954 isbn 978-952-67497-3-0 Copyright c 2019 The Authors and the Nordic Pragmatism Network. This work is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported License. CC BY NC For more information, see http://creativecommons.org/licenses/by-nc/3.0/ Nordic Pragmatism Network, NPN Helsinki 2019 www.nordprag.org Anti-Kantianism as a Necessary Characteristic of Pragmatism Giovanni Maddalena Universit`adel Molise 1. Introduction Pragmatists declared their anti-Cartesianism at the first appearance of the movement, in Peirce’s series on cognition written for the Journal of Specu- lative Philosophy (1867–8). As is well known, the brilliant young scientist characterized Cartesian doubt as a “paper doubt”, by opposing it to sci- entists’ true “living doubt” (Peirce 1998 [1868], 115).1 Some readers have not understood the powerful novelty that his opposition to Cartesianism implies. According to Peirce, research does not proceed from skeptical, “paper” doubt. For Peirce, doubt is possible because of a previous cer- tainty, a position which is similar to the one held by Augustine (Augustine 1970). Research moves from one certainty to another; the abandonment of an initial certainty is only reasonable in the presence of a real and surprising phenomenon that alters one of the pillars on which it stands. -
Constructivity in Homotopy Type Theory
Ludwig Maximilian University of Munich Munich Center for Mathematical Philosophy Constructivity in Homotopy Type Theory Author: Supervisors: Maximilian Doré Prof. Dr. Dr. Hannes Leitgeb Prof. Steve Awodey, PhD Munich, August 2019 Thesis submitted in partial fulfillment of the requirements for the degree of Master of Arts in Logic and Philosophy of Science contents Contents 1 Introduction1 1.1 Outline................................ 3 1.2 Open Problems ........................... 4 2 Judgements and Propositions6 2.1 Judgements ............................. 7 2.2 Propositions............................. 9 2.2.1 Dependent types...................... 10 2.2.2 The logical constants in HoTT .............. 11 2.3 Natural Numbers.......................... 13 2.4 Propositional Equality....................... 14 2.5 Equality, Revisited ......................... 17 2.6 Mere Propositions and Propositional Truncation . 18 2.7 Universes and Univalence..................... 19 3 Constructive Logic 22 3.1 Brouwer and the Advent of Intuitionism ............ 22 3.2 Heyting and Kolmogorov, and the Formalization of Intuitionism 23 3.3 The Lambda Calculus and Propositions-as-types . 26 3.4 Bishop’s Constructive Mathematics................ 27 4 Computational Content 29 4.1 BHK in Homotopy Type Theory ................. 30 4.2 Martin-Löf’s Meaning Explanations ............... 31 4.2.1 The meaning of the judgments.............. 32 4.2.2 The theory of expressions................. 34 4.2.3 Canonical forms ...................... 35 4.2.4 The validity of the types.................. 37 4.3 Breaking Canonicity and Propositional Canonicity . 38 4.3.1 Breaking canonicity .................... 39 4.3.2 Propositional canonicity.................. 40 4.4 Proof-theoretic Semantics and the Meaning Explanations . 40 5 Constructive Identity 44 5.1 Identity in Martin-Löf’s Meaning Explanations......... 45 ii contents 5.1.1 Intensional type theory and the meaning explanations 46 5.1.2 Extensional type theory and the meaning explanations 47 5.2 Homotopical Interpretation of Identity ............ -
The Proper Explanation of Intuitionistic Logic: on Brouwer's Demonstration
The proper explanation of intuitionistic logic: on Brouwer’s demonstration of the Bar Theorem Göran Sundholm, Mark van Atten To cite this version: Göran Sundholm, Mark van Atten. The proper explanation of intuitionistic logic: on Brouwer’s demonstration of the Bar Theorem. van Atten, Mark Heinzmann, Gerhard Boldini, Pascal Bourdeau, Michel. One Hundred Years of Intuitionism (1907-2007). The Cerisy Conference, Birkhäuser, pp.60- 77, 2008, 978-3-7643-8652-8. halshs-00791550 HAL Id: halshs-00791550 https://halshs.archives-ouvertes.fr/halshs-00791550 Submitted on 24 Jan 2017 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Distributed under a Creative Commons Attribution - NonCommercial| 4.0 International License The proper explanation of intuitionistic logic: on Brouwer’s demonstration of the Bar Theorem Göran Sundholm Philosophical Institute, Leiden University, P.O. Box 2315, 2300 RA Leiden, The Netherlands. [email protected] Mark van Atten SND (CNRS / Paris IV), 1 rue Victor Cousin, 75005 Paris, France. [email protected] Der … geführte Beweis scheint mir aber trotzdem . Basel: Birkhäuser, 2008, 60–77. wegen der in seinem Gedankengange enthaltenen Aussagen Interesse zu besitzen. (Brouwer 1927B, n. 7)1 Brouwer’s demonstration of his Bar Theorem gives rise to provocative ques- tions regarding the proper explanation of the logical connectives within intu- itionistic and constructivist frameworks, respectively, and, more generally, re- garding the role of logic within intuitionism. -
THE LOOICAL ATOMISM J. D. MACKENZIE Date Submitted Thesis
THE LOOICAL ATOMISM OF F. P. RAMSEY J. D. MACKENZIE Date submitted Thesis submitted for the Degree of Master of Arts in the School of Philosophy University of New South Wales (i) SYNOPSIS The first Chapter sets Ramsey in histor:iealperspective as a Logical Atomist. Chapter Two is concerned with the impasse in which Russell found himself ,d.th general propositions, Wittgenstein's putative solution in terms of his Doctrine of Showing, and Ramsey's "Wittgensteinian" solution, which is not satisfactory. An attempt is then ma.de to describe a Ramseian solution on the basis of what he says about the Axiom of Infi- nity, and to criticize this solution. In Chapter Three Ramsay's objections to the Pl4 definition of identity are considered, and consequences of his rejection of that definition for the Theory of Classes and the Axiom of Choice are drawn. In Chapter Four, Ramsey•s modifications to Russell's Theory of Types are discussed. His division of the Paradoxes into two groups is defended, but his redefinition of 'predicative' is rejected. Chapter Five deals with Ra.msey's analysis of propositional attitudes and negative propositions, and Chapter Six considers the dispute between Russell and Ramsey over the nature and status of universals. In Chapter Seven, the conclusions are summarized, and Ramsay's contribution to Logical Atom.ism are assessed. His main fail ing is found to be his lack of understanding of impossibility, especially with regard to the concept of infinity. (ii) PREFACE The thesis is divided into chapters, which are in turn divided into sections. -
Understanding Intuitionism
Understanding Intuitionism by Edward Nelson Department of Mathematics Princeton University http:==www.math.princeton.edu= nelson=papers.html ∼ Intuitionism was the creation of L. E. J. Brouwer [Br], and I like to think that classical mathematics was the creation of Pythagoras. Imag- ine a conversation between a classical mathematician and an intuitionist, say a woman and a man respectively. She speaks first: I have just proved xA. Congratulations! What9 is it? I don't know. I assumed x A and derived a contradiction. Oh. You proved x A.8 : That's what I said.:8 : Or another: I have proved A B. Good. Which did_ you prove? What? You said you proved A or B; which did you prove? Neither; I assumed A & B and derived a contradiction. Oh, you proved [ :A & :B]. That's right. It's: another: : way of putting the same thing. But he does not agree with her last statement; they have a different semantics and a different notion of proof. This paper is an attempt to understand the differences between them. I am grateful to Mitsuru Yasuhara for stimulating discussions of this material and for pinpointing errors and obscurities in earlier drafts. I also wish to thank Simon Kochen and Per Martin-L¨offor helpful comments. 1. Incomplete communications For a classical mathematician, a closed formula, true in a given structure, is a complete communication. It expresses an objective state of affairs in the universe of discourse; it is an ontological assertion. But 1 2 1. INCOMPLETE COMMUNICATIONS to an intuitionist, a closed true formula may be an incomplete communi- cation. -
Intuition As Evidence in Philosophical Analysis: Taking Connectionism Seriously
Intuition as Evidence in Philosophical Analysis: Taking Connectionism Seriously by Tom Rand A thesis submitted in conformity with the requirements for the degree of Ph.D. Graduate Department of Philosophy University of Toronto (c) Copyright by Tom Rand 2008 Intuition as Evidence in Philosophical Analysis: Taking Connectionism Seriously Ph.D. Degree, 2008, by Tom Rand, Graduate Department of Philosophy, University of Toronto ABSTRACT 1. Intuitions are often treated in philosophy as a basic evidential source to confirm/discredit a proposed definition or theory; e.g. intuitions about Gettier cases are taken to deny a justified-true-belief analysis of ‘knowledge’. Recently, Weinberg, Nichols & Stitch (WN&S) provided evidence that epistemic intuitions vary across persons and cultures. In- so-far as philosophy of this type (Standard Philosophical Methodology – SPM) is committed to provide conceptual analyses, the use of intuition is suspect – it does not exhibit the requisite normativity. I provide an analysis of intuition, with an emphasis on its neural – or connectionist – cognitive backbone; the analysis provides insight into its epistemic status and proper role within SPM. Intuition is initially characterized as the recognition of a pattern. 2. The metaphysics of ‘pattern’ is analyzed for the purpose of denying that traditional symbolic computation is capable of differentiating the patterns of interest. 3. The epistemology of ‘recognition’ is analyzed, again, to deny that traditional computation is capable of capturing human acts of recognition. 4. Fodor’s informational semantics, his Language of Thought and his Representational Theory of Mind are analyzed and his arguments denied. Again, the purpose is to deny traditional computational theories of mind. -
The Oberlin Colloquium in Philosophy: Program History
The Oberlin Colloquium in Philosophy: Program History 1960 FIRST COLLOQUIUM Wilfrid Sellars, "On Looking at Something and Seeing it" Ronald Hepburn, "God and Ambiguity" Comments: Dennis O'Brien Kurt Baier, "Itching and Scratching" Comments: David Falk/Bruce Aune Annette Baier, "Motives" Comments: Jerome Schneewind 1961 SECOND COLLOQUIUM W.D. Falk, "Hegel, Hare and the Existential Malady" Richard Cartwright, "Propositions" Comments: Ruth Barcan Marcus D.A.T. Casking, "Avowals" Comments: Martin Lean Zeno Vendler, "Consequences, Effects and Results" Comments: William Dray/Sylvan Bromberger PUBLISHED: Analytical Philosophy, First Series, R.J. Butler (ed.), Oxford, Blackwell's, 1962. 1962 THIRD COLLOQUIUM C.J. Warnock, "Truth" Arthur Prior, "Some Exercises in Epistemic Logic" Newton Garver, "Criteria" Comments: Carl Ginet/Paul Ziff Hector-Neri Castenada, "The Private Language Argument" Comments: Vere Chappell/James Thomson John Searle, "Meaning and Speech Acts" Comments: Paul Benacerraf/Zeno Vendler PUBLISHED: Knowledge and Experience, C.D. Rollins (ed.), University of Pittsburgh Press, 1964. 1963 FOURTH COLLOQUIUM Michael Scriven, "Insanity" Frederick Will, "The Preferability of Probable Beliefs" Norman Malcolm, "Criteria" Comments: Peter Geach/George Pitcher Terrence Penelhum, "Pleasure and Falsity" Comments: William Kennick/Arnold Isenberg 1964 FIFTH COLLOQUIUM Stephen Korner, "Some Remarks on Deductivism" J.J.C. Smart, "Nonsense" Joel Feinberg, "Causing Voluntary Actions" Comments: Keith Donnellan/Keith Lehrer Nicholas Rescher, "Evaluative Metaphysics" Comments: Lewis W. Beck/Thomas E. Patton Herbert Hochberg, "Qualities" Comments: Richard Severens/J.M. Shorter PUBLISHED: Metaphysics and Explanation, W.H. Capitan and D.D. Merrill (eds.), University of Pittsburgh Press, 1966. 1965 SIXTH COLLOQUIUM Patrick Nowell-Smith, "Acts and Locutions" George Nakhnikian, "St. Anselm's Four Ontological Arguments" Hilary Putnam, "Psychological Predicates" Comments: Bruce Aune/U.T. -
Constructive Logic for All
Constructive Logic for All Greg Restall∗ Philosophy Department Macquarie University June 14, 2000 Abstract It is a commonplace in recent metaphysics that one's logical commit- ments go hand in hand with one's metaphysics. Brouwer, Heyting and Dummett have each championed the move to constructive (intuitionistic) reasoning on the grounds of anti-realism. I hope to break this close connec- tion, to explain why a realist ought to reason constructively. 1 Introduction Let me start by explaining the terms of the discussion. In this area of philo- sophical logic there seems to be some confusion in the use of terms such as “intuitionistic” and “constructive.” It will help to get the use of these terms somewhat fixed before I start to argue my case. 1.1 Logic First, logic. The subject Logic is the study of logical consequence. Logical con- sequence is a matter of the validity and invalidity of arguments. An argument is valid just when in any case in which the premises of the argument are true, so is the conclusion. It is often helpful, in discussing logical consequence, to have a formal language in which to express the premises and conclusions of ar- guments. One such language is the language of first-order logic, with primitive expressions for the connectives and quantifiers ^ conjunction _ disjunction conditional ⊃ ∼ negation x universal quantifier 8 (with x a variable) x existential quantifier 9 (with x a variable) For some, logic is at heart the study of the behaviour of these connectives. For others, the singling out of particular parts of the language is an incidental mat- ter. -
Paraconsistency and Duality
Paraconsistency and duality: between ontological and 1 epistemological views 1 2 WALTER CARNIELLI AND ABILIO RODRIGUES 2 Abstract: The aim of this paper is to show how an epistemic approach to paraconsistency may be philosophically justified based on the duality be- tween paraconsistency and paracompleteness. The invalidity of excluded middle in intuitionistic logic may be understood as expressing that no con- 3 structive proof of a pair of propositions A and :A is available. Analogously, in order to explain the invalidity of the principle of explosion in paraconsis- tent logics, it is not necessary to consider that A and :A are true, but rather that there are conflicting and non-conclusive evidence for both. Keywords: Paraconsistent logic, Philosophy of paraconsistency, Evidence, Intuitionistic logic 4 1 Introduction 5 Paraconsistent logics have been assuming an increasingly important place 6 in contemporary philosophical debate. Although from the strictly techni- 7 cal point of view paraconsistent formal systems have reached a point of 8 remarkable development, there are still some aspects of their philosophi- 9 cal significance that have not been fully explored yet. The distinctive fea- 10 ture of paraconsistent logics is that the principle of explosion, according to 11 which anything follows from a contradiction, does not hold, thus allowing 12 for the presence of contradictions without deductive triviality. Dialetheism 13 is the view according to which there are true contradictions (cf. e.g. Priest 14 1The first author acknowledges support from FAPESP (Fundação de Amparo à Pesquisa do Estado de São Paulo, thematic project LogCons) and from a CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico) research grant. -
How to Cite Complete Issue More Information About This Article
THEORIA. Revista de Teoría, Historia y Fundamentos de la Ciencia ISSN: 0495-4548 ISSN: 2171-679X [email protected] Universidad del País Vasco/Euskal Herriko Unibertsitatea España Miguel Sagüillo, José Hilary Putnam on the philosophy of logic and mathematics* [1] THEORIA. Revista de Teoría, Historia y Fundamentos de la Ciencia, vol. 33, no. 2, 2018, pp. 183-200 Universidad del País Vasco/Euskal Herriko Unibertsitatea España DOI: https://doi.org/10.1387/theoria.17626 Available in: https://www.redalyc.org/articulo.oa?id=339755528003 How to cite Complete issue Scientific Information System Redalyc More information about this article Network of Scientific Journals from Latin America and the Caribbean, Spain and Journal's webpage in redalyc.org Portugal Project academic non-profit, developed under the open access initiative THEORIA ESTABLISH E D IN 1952 BY MIGU E L SÁNCH E Z -MAZAS Vol. 33/2 • May 2018 Second Series An International Journal for Theory, History and Foundations of Science CALIJ Centro de Análisis, Lógica e Informática Jurídica (CALIJ) http://www.ehu.eus/theoria T H E O R I A REVISTA DE TEORÍA, HISTORIA Y FUNDAMENTOS DE LA CIENCIA AN INTERNATIONAL JOURNAL FOR THEORY, HISTORY AND FOUNDATIONS OF SCIENCE ESTABLISH E D in 1952 by MIGUEL SÁNCHEZ-MAZAS Second Series EDITORIAL BOARD Editor-in-chief: Andoni IBARRA (University of the Basque Country, UPV/EHU) Editors: Cristina CORREDOR (Universidad de Valladolid), Antonio DIÉGUEZ (Universidad de Málaga) Logic and philosophy of logic and mathematics: José Luis ZALABARDO (University College -
Scott Soames, Philosophical Analysis in the Twentieth Century: Volume 1: the Dawn of Analysis Princeton University Press, 2003
Philos Stud (2006) 129:637–643 DOI 10.1007/s11098-006-0015-3 DISCUSSION Scott Soames, Philosophical Analysis in the Twentieth Century: Volume 1: The Dawn of Analysis Princeton University Press, 2003 R.M. Sainsbury Accepted: 27 March 2006 Ó Springer Science+Business Media B.V. 2006 The jacket of this first volume of the two volume work tells us that this is a history of analytic philosophy from 1900 to mid-century. Accordingly, we can properly eval- uate it under three heads: (1) the care and accuracy of the scholarship; (2) the light it throws on the relationships among the various activities it describes; and (3) the quality of the philosophical argumentation. Evaluated under the third, the book deserves high praise. It provides serious philosophy: arguments are carefully set out and taken to pieces, objections and possible responses are developed in an orderly way. Most readers will learn something of philosophical value, and even on the issues about which they disagree with Soames, they will find him a worthy and helpful opponent. In this respect the text provides a model to which students should aspire. Every page demonstrates one way in which philosophy can be done excel- lently, as will be no surprise to those familiar with Soames’s other work. Evaluated under the other two heads, however, the book in my judgement falls short. Not only are there historical inaccuracies, the approach to reading, evaluating and interpreting texts is one I find uncongenial; and the attempt to impose some kind of overall developmental themes on the material under discussion strikes me as unsuccessful. -
Intuitionism and Logical Revision
UNIVERSITY OF SHEFFIELD Intuitionism and Logical Revision Julien Murzi A thesis submitted in partial fulfillment for the degree of Doctor of Philosophy Faculty of Arts and Humanities Department of Philosophy Sheffield October 2010 To my parents. To Barbara. To Bob and Dam. Abstract The topic of this thesis is logical revision: should we revise the canons of classical reasoning in favour of a weaker logic, such as intuitionistic logic? In the first part of the thesis, I consider two metaphysical arguments against the classical Law of Excluded Middle-arguments whose main premise is the metaphysical claim that truth is knowable. I argue that the first argument, the Basic Revisionary Argument, validates a parallel argument for a conclusion that is unwelcome to classicists and intuitionists alike: that the dual of the Law of Excluded Middle, the Law of Non-Contradiction, is either unknown, or both known and not known to be true. As for the second argument, the Paradox of Knowability, I offer new reasons for thinking that adopting intuitionistic logic does not go to the heart of the matter. In the second part of the thesis, I motivate an inferentialist framework for assessing competing logics-one on which the meaning of the logical vocabulary is determined by the rules for its correct use. I defend the inferentialist account of understanding from the contention that it is inadequate in principle, and I offer reasons for thinking that the inferentialist approach to logic can help model- theorists and proof-theorists alike justify their logical choices. I then scrutinize the main meaning-theoretic principles on which the inferentialist approach to logic rests: the requirements of harmony and separability.