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University of Calgary

Department of Philosophy

2500 University Drive NW

Calgary, Alberta T2N 1N4

Canada

Web: richardzach.org

EMail: rzach@ucalgary.ca

Phone: +1 (403) 220 3170

Twitter: rrrichardzach

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Philpapers

ORCID: 0000-0003-1633-8324

PhD, **University of California, Berkeley**, Logic and the Methodology of Science, 2001

- Thesis: "Hilberts Finitism: Historical, Philosophical, and Metamathematical Perspectives." Supervisors: Paolo Mancosu, Jack H. Silver

MA, **University of California, Berkeley**, Mathematics, 1997

CPhil, **University of California, Berkeley**, Logic and the Methodology of Science, 1997

Diplom-Ingenieur, **Technische Universität Wien**, Computational Logic, 1993

- Thesis: "Proof Theory of Finite-Valued Logics." Supervisor: Matthias Baaz

Logic: Proof Theory, Non-classical Logics

History of Logic: Hilbert, Gödel, Carnap

Philosophy of Mathematics: Hilbert's Program

History of Analytic Philosophy: Carnap

Metaphysics, Philosophy of Language, Philosophy of Science

Professor. 2009-.

Associate Professor. 2004-2009.

Assistant Professor. 2001-2004.

Visiting Professor. 2014-2015.

Visiting Associate Researcher. 2004-2004.

Lecturer. 2001-2001.

Graduate Student Instructor. 1996-2000.

Erasmus Mundus Scholar. 2009-2009.

Lecturer. 1995-2000.

*Journal for the History of Analytic Philosophy*, Founding Editor. 2010-.

*Open Logic Project*, Main Instigator. 2013-.

*The Collected Works of Rudolf Carnap*, Editor. 2006-.

*Studia Logica*, Associate Editor. 2006-.

*Stanford Encyclopedia of Philosophy*, Subject Editor, History of Logic. 2005-.

*Hilbert-Bernays Project*, Advisory Board Member. 2008-.

*Paul Bernays Project*, Editorial Board Member. 2000-.

*The Review of Symbolic Logic*, Founding Editor. 2007-2013.

Scholarship of Teaching and Learning Grant, University of Calgary, "Logic for the 21st Century," CAD 36,820, 2016–2017 (Co-applicants: Nicole Wyatt and Aaron Thomas-Bolduc).

Teaching and Learning Practice Grant, University of Calgary, "The Open Logic Project," CAD 7,500, 2015–2016 (Co-applicant: Nicole Wyatt).

Alberta Open Educational Resources Intitiative, "The Open Logic Project," CAD 43,000, 2015.

Annual Fellowship, "Calgary Institute for the Humanities," , 2013–2014.

Insight Grant, Social Sciences and Humanities Research Council of Canada (SSHRC), "The Collected Works of Rudolf Carnap (Phase 2)," CAD 133,680, 2012–2017 (Co-applicant: Dirk Schlimm, McGill University).

Visiting Scholar Grant, University of Calgary Research Grants Committee, "Nuel Belnap, University of Pittsburgh," CAD 1,275, 2009.

Standard Research Grant, Social Sciences and Humanities Research Council of Canada (SSHRC), "The Collected Works of Rudolf Carnap," CAD 64,900, 2008–2011 (Co-applicant: Dirk Schlimm, McGill University).

Discovery Grant, Natural Sciences and Engineering Research Council of Canada (NSERC), "Computational Aspects of the Epsilon Calculus," CAD 70,000, 2007–2012.

Conference Grant, University of Calgary Research Grants Committee, "Mathematical Methods in Philosophy," CAD 6,000, 2006.

Calgary Institute for the Humanities Annual Fellowship, teaching release, 2006–2007.

Short Term Project Grant, University of Calgary Research Grants Committee, "The Essential Carnap," CAD 5,940, 2006.

Travel Grant, University of Calgary Research Grants Committee,, "International Symposium on Multiple Valued Logic, Singapore," CAD 1,500, 2006.

Visiting Scholar Grant, University of Calgary Research Grants Committee, "John P. Burgess, Princeton University," CAD 1,300, 2004.

Visiting Scholar Grant, University of Calgary Research Grants Committee, "William W. Tait, University of Chicago," CAD 1,150, 2004.

Standard Research Grant, Social Sciences and Humanities Research Council of Canada (SSHRC), "The History of Logical Metatheory, 1900–1940," CAD 68,200, 2004–2007.

Discovery Grant, Natural Sciences and Engineering Research Council of Canada (NSERC), "Gödel Logics: Foundations and Applications in Computer Science," CAD 38,000, 2003–2007.

Canadian Hunter Young Innovator Award, University of Calgary, "Gödel Logics: Foundations and Applications in Computer Science," CAD 20,000, 2003.

Travel Grant, University of Calgary Research Grants Committee, "International Symposium on Multiple Valued Logic, Tokyo, May 2003," CAD 1,500, .

Professional Development Grant, Faculty of Humanities, CAD 2,000, 2003.

Visiting Scholar Grant, University of Calgary Research Grants Committee, "Matthias Baaz, Technische Universität Wien," CAD 1,850, 2002.

Professional Development Grant, Faculty of Humanities, CAD 2,000, 2002.

Starter Grant, University of Calgary Research Grants Committee, "The Golden Age of Logic: The Development of Logical Metatheory," CAD 10,000, 2002–2003.

Professional Development Grant, Faculty of Humanities, CAD 2,000, 2001.

Research Excellence Envelope Grant, University of Calgary, CAD 15,000., 2001–2002.

Graduate Program Director. 2015-.

Committee on Diversity and Climate, Member. 2015–.

Head's Advisory Committee, Member. 2013–2014, 2015–.

Graduate Studies Committee, Member. 2002–2004, 2005–2006, 2009–2013.

Hiring Committee (Logic and Philosophy of Science), Member. 2012.

Speaker's Committe, Chair. 2008–2011.

Hiring Committee (Logic and Philosophy of Science Postdoc), Member. 2010.

Speaker's Committee, Member. 2005.

Preliminary Exam Standing Committee (Logic and Language), Chair. 2003–2004, 2008–2014.

Field of Study Exam Standing Committee (Logic and Language), Member. 2015–.

Hiring Committee (Logic), Member. 2005–2006.

Placement Director. 2002–2004, 2005, 2009.

History and Philosophy of Science Programs, Co-Director. 2003–2004, 2005–2006.

Hiring Committee (Epistemology), Member. 2005–2006.

Webmaster. 2001–2008.

Hiring Committee (Philosophy of Science), Member. 2004.

Ad Hoc Committee on History and Philosophy of Science Undergraduate Programs, Chair. 2002–2003.

Ad Hoc Committee on Department Self-Assessment Exercise, Member. 2002.

Faculty of Graduate Studies, Awards Oversight Committee. 2016–.

Faculty of Arts, Tenure and Promotion Committee, Dean's Appointee. 2016-2017.

Pacific Institute for the Mathematical Sciences, Calgary Site Steering Committee. 2016-.

Taylor Institute for Teaching and Learning, Advisory Board to the Academic Director. 2016-.

VP Teaching and Learning, Open Educational Resources Working Group. 2016–.

Calgary Mathematics and Philosophy Lecture Series, Department of Philosophy and Pacific Institute for the Mathematical Sciences, Organizer. 2015–.

Calgary Institute for the Humanities, Executive Council. 2016-2018.

Institute for Quantum Science and Technology, Council. 2010-.

Calgary Peripatetic Research Group on Logic and Category Theory, Co-organizer. 2001-.

Faculty of Arts, Executive Committee. 2011-2013.

Faculty of Humanities, Sabbatical Fellowship Committee. 2008-2009.

Faculty of Graduate Studies, Graduate Scholarships Committee. 2004-2005.

Department of Religious Studies, Headship Selection Committee. 2004.

Faculty of Humanities, Representative to Faculty of Science. 2003-2005.

Faculty of Humanities, Promotions Committee, Observer (Dean's Appointee). 2004.

Faculty of Humanities, Executive Committee, Member. 2001-2004.

History and Philosophy of Logic, Mathematics, and Science Townsend Center Working Group, Organizer. 1998-2001.

Graduate Council, Advisory Committee on Graduate Student Instructor Affairs, Student Representative. 1997-1999.

Graduate Assembly, Committee on the Educational Improvement Grant Program, Member. 1997-1998.

Logic and Methodology of Science Graduate Student Association, President. 1995-1998.

Logic and Methodology of Science Graduate Student Association, Graduate Assembly Delegate. 1995-1998.

Academic Senate, Advisory Committee to the on International Education, Student Representative. 1995-1996.

Association for Symbolic Logic, Membership Committee, Member. 2016–.

Society for the Study of the History of Analytic Philosophy, Secretary. 2015–.

Special Interest Group on Logic and Computation of the ACM, Education Committee, Member. 2014–.

Association for Symbolic Logic, Website Committee, Member. 2014–.

Kurt Gödel Society, Executive Board, Member. 1992–94, 2005–.

Association for Symbolic Logic, Nominating Committee, Member. 2015–2016.

Philosophy of Mathematics Association, Executive Board, Member. 2015–2016.

Philosophy of Mathematics Association, Nominating Committee, Member. 2014–2016.

Society for the Study of the History of Analytic Philosophy, Board Member. 2009–2015.

Association for Symbolic Logic, Committee on Logic Education, Chair. 2009–2011.

Canadian Society for the History and Philosophy of Science, Advisory Board, Member. 2008–2011.

Association for Symbolic Logic, Council, Elected Member. 2008–2010.

Association for Symbolic Logic, Committee on Logic Education, Member. 2002–2008.

Quantifiers and Determiners QUAD 2017, ESSLLI, Program Committee Member. 2017.

Annual Meeting of the Society for the History of Analytic Philosophy, University of Calgary, Organizer. 2017.

Spring Meeting of the Association for Symbolic Logic, Seattle, Program Committee Chair. 2017.

Annual Meeting of the Canadian Society for History and Philosophy of Mathematics, University of Calgary, Local Organizer. 2016.

Annual Meeting of the Association for Symbolic Logic, University of Connecticut, Special Session Organizer. 2016.

Summer Program for Diversity in Logic, University of Massachussetts, Dartmouth, Advisory Board Member.

Epsilon 2015: Hilbert's Epsilon and Tau in Logic, Informatics and Linguistics, Program Committee Member. 2015.

Pacific Division of the American Philosophical Association, Program Committee Member. 2012-2015.

Vienna Summer of Logic, Organizing Committee Member. 2014.

Logic, Algebra, and Truth Degrees LATD 2014, Program Committee Member. 2014.

Logic Colloquium: European Summer Meeting of the Association for Symbolic Logic, Vienna, Program Committee Member. 2014.

Logic, Algebra, and Truth Degrees LATD 2013, Program Committee Member. 2013.

Third International Congress on Tools for Teaching Logic, Program Committee Member. 2011.

Carnap and the Legacy of Logical Empiricism, Institute Vienna Circle, Vienna, Organizer. 2010.

Computability in Europe CiE, Program Committee Member. 2009.

Logic Miniconference (Aldo Antonelli, Nuel Belnap, Krister Segerberg), University of Calgary, Organizer. 2009.

Mathematical Applications in Philosophy, Banff International Research Station, Organizer. 2007.

Uncertainty: Reasoning about Vagueness and Probability, Program Committee, Member. 2006.

Logic Miniconference (John Burgess, Kit Fine, Alasdair Urquhart), University of Calgary, Organizer. 2005.

Annual Congress of the Canadian Philosophical Association, Program Committee Member. 2005.

Spring Meeting of the Association for Symbolic Logic, Program Committee Member. 2005.

Stanford-Berkeley Graduate Philosophy Conference, Organizing Committee Member. 1996–1998.

Fifth Kurt Gödel Colloquium, Vienna, Organizing Committee Member. 1997.

Lecture Series "Collegium Logicum", Organizing Committee Chair. 1992–1994.

Workshop on Proof Theory, Complexity, Metamathematics, Vienna, Organizing Committee Chair. 1994.

Third Kurt Gödel Colloquium, Brno, Organizing Committee Member. 1993.

Presses: Blackwell, Cambridge University Press, Oxford University Press, Princeton University Press.

Journals: *Archive for Mathematical Logic*, *American Philosophical Quarterly*, *Bulletin of Symbolic Logic*, *Dialectica*, *Ergo*, *Erkenntnis*, *European Journal for Philosophy of Science*, *Historia Mathematica*, *History and Philosophy of Logic*, *Journal of Philosophical Logic*, *Journal of Symbolic Logic*, *Journal of Applied Non-Classical Logics*, *Journal of Logic and Computation*, *Journal of Logic, Language, and Information*, *Logic Journal of the IGPL*, *Journal for the History of Analytic Philosophy*, *Mathematical Logic Quarterly*, *Mind*, *Notre Dame Journal of Formal Logic*, *Philosopher's Imprint*, *Philosophia Mathematica*, *Review of Symbolic Logic*, *Studia Logica*, *Studies in History and Philosophy of Science*, *Synthese*, *Theoretical Computer Science*.

Conferences: Canadian Philosophical Association 2003, 2006, 2008, 2017; Workshops on Computer Science Logic 1994, 1995, 2002, 2017;Western Canadian Philosophy Association 2002, 2004, 2016; Computability in Europe 2008; Logic for Programming and Automated Reasoning 1992, 2005, 2007; World Congress on Universal Logic 2005; Society for Exact Philosophy 2005; International Joint Conference on Automated Reasoning 2004; International Symposia on Multiple Valued Logic 1994, 1998; Kurt Gödel Colloquia 1993, 1997; International Conference on Automated Deduction 1994, 2004; European Conference on Artificial Intelligence 1994; Workshop on Tableau-based Deduction, 1993.

Granting Agencies: Austrian Science Fund, Fonds Québéquois de Recherche sur la Société et Culture, Natural Sciences and Engineering Research Council of Canada NSERC, Research Foundation Flanders, Social Sciences and Humanities Research Council of Canada SSHRC, Deutsche Forschungsgemeinschaft, Canada Council for the Arts, Nederlands Organization for Scientific Research.

The Decision Problem and Logical Metatheory. SoMLaFS Colloquium, The Ohio State University, 2017.

Substitution, Consequence, and Proof, or: How Many Consequence Relations Can One Logic Have?. Department of Philosophy, University of British Columbia, Okanagan, 2016.

Derivation and Consequence. Philosophy Workshop, McGill University, 2015.

The Decision Problem and Logical Metatheory. Townsend Center Working Group in History and Philosophy of Logic, Mathematics, and Science, University of California, Berkeley, 2014.

Carnap and Logic in the 1920s and 1930s. Minnesota Center for Philosophy of Science, University of Minnesota, 2014.

The Decision Problem and Logical Metatheory. Foundations Interest Group, Department of Philosophy, University of Minnesota, 2014.

The Decision Problem and the Development of Metalogic. Logic and Philosophy of Science Group, University of Toronto, 2012.

Gödel's First Incompleteness Theorem and Mathematical Instrumentalism. Keio University, Tokyo, 2011.

Proof Interpretations and the Constructive Content of Mathematical Theories. Kyoto University, 2011.

The Epsilon Calculus. Keio University, Tokyo, 2011.

The Decision Problem and the Development of Metalogic. Department of Philosophy, McGill University, 2009.

Proof Interpretations and the Constructive Content of Mathematical Theories. Wissenschaftstheoretisches Kolloquium, University of Vienna, Austria, 2009.

The Decision Problem and the Development of Metalogic. Department of Philosophy, Utrecht University, 2008.

Proof Construction, and Computation: Interactions between Philosophy of Mathematics and Mathematical Foundations. Scuola Normale Superiore, Pisa, 2008.

The Epsilon Calculus. Logic Group, University of Melbourne, 2006.

Logic and Cagueness. Department of Philosophy, University of Melbourne, 2006.

Gödel's First Incompleteness Theorem and Mathematical Instrumentalism. Gödel Seminar, University of Notre Dame, 2006.

Algebraic Semantics for Logics of Vagueness. Kurt Gödel Society, University of Technology, Vienna, 2005.

What Should a Logic of Vagueness Be and Do?. Philosophy Department, Stanford University, 2005.

How to Argue for and against a Logic of Vagueness. Logic and Philosophy of Science Colloquium, University of California, Irvine, 2004.

Gödel's First Incompleteness Theorem and Mathematical Instrumentalism. Department of Philosophy, University of Lethbridge, 2004.

Completeness and Decidability in the Context of Hilbert's Philosophy. Department of Philosophy, University of Alberta, 2003.

The Early History of the Epsilon Calculus. Townsend Center Working Group in History and Philosophy of Logic, Mathematics, and Science, University of California, Berkeley, 2002.

Logic and Metalogic in Hilbert's School. Seminari de Lògica, Universitat de Barcelona, 2002.

Finitism and Mathematical Intuition. Department of Philosophy, Oxford University, 20008.

Finitism and Mathematical Intuition. Department of Philosophy, University of Chicago, 2000.

Finitism and Mathematical Intuition. Department of Philosophy, Stanford University, 2000.

Completeness before Post: Hilbert and Bernays on Propositional Logic, 1917–18. Logic Lunch, Stanford University, 1999.

The Debate between Kreisel and Tait on Finitism. Colloquium Logico-Philosophicum, Universität Erlangen-Nürnberg, 1998.

Finitism. Kurt Gödel Society, Vienna, 1997.

Generalization of Theorems and Proofs: Kreisel's Conjecture for Algebraic Theories. Logic Lunch, Stanford University, 1997.

Axiomatizability Issues in Temporal and Infinite-Valued First-Order Logics. Equipe de Logique, Université Paris 7 Denis Diderot, 1995.

Adventures in Many-Valued Logic. Kurt Gödel Society, Vienna, 1995.

Semantics and Proof Theory of the Epsilon Calculus. *Indian Conference on Logic and its Applications*, Indian Institute of Technology, Kanpur, 2017.

Carnap on Models. *Spring Meeting of the Association for Symbolic Logic, Symposium on Metalogic and Early Analytic Philosophy*, San Diego, 20147.

The Epsilon Calculus: An Undervalued Logical Formalism. *Annual Meeting of the Society for Exact Philosophy*, Montréal, 2013.

Carnap, Logic, and Analytic Philosophy. *200 Years of Analytic Philosophy*, University of Latvia, Rīga, 2008.

The decision problem and the development of metalogic. *Annual Meeting of the Association for Symbolic Logic*, University of Florida, Gainesville, FL, 20072.

Kurt Gödel and computability theory. *Computability in Europe CiE 2006: Logical Approaches to Computational Barriers*, Swansea, Wales, 2006.

The Epsilon Calculus. *Kurt Gödel Colloquium/Conference on Computer Science Logic CSL'03*, University of Technology Vienna, 2003.

The Open Logic Project. *Spring Meeting of the Association for Symbolic Logic, Special Session on Diversity in Logic Education*, Seattle, 2017.

General Rules for Sequent Calculus and Natural Deduction. *OSU/UConn Workshop on Truth*, The Ohio State University, 2017.

The Fruitfulness of Philosophy of Mathematics. *Workshop on Mathematics and Culture*, Indian Institute of Engineering Science and Technology, Shibpur, 2017.

Carnap as a Logician. *Carnap on Logic Conference*, Munich Center for Mathematical Philosophy, 2013.

Carnap and Logic. *Workshop on Formal Epistemology and the Legacy of Logical Empiricism*, University of Texas, Austin, 2013.

"Principia Mathematica" and the development of logic. _PM@100_, McMaster University, Hamilton, 20103.

Bernays and the Decision Problem in Hilbert's School. *Bernaysfest*, Carnegie Mellon University, 2008.

Carnap's Logic in the 1930s. *Annual Meeting of the Association for Symbolic Logic, Special Session on Logic and Logical Empiricism*, University of California, Irvine, 2008.

Analytic Systems for the *ε*-Calculus. *Analytic Systems/LPAR 2007*, Yerevan, Armenia, 2007.

The Decision Problem in the 1920s. *Moscow-Vienna Workshop on Logic and Computation*, Technical University Vienna, Vienna, Austria, 2007.

Algorithms and decision problems in Hilbert's school. *Hilbert Workshop*, Kyoto University, 2006.

Vagueness and Fuzzy Logics. *Uncertainty: Reasoning about Probability and Vagueness*, Prague, 2006.

Gödel's First Incompleteness Theorem and Mathematical Instrumentalism. *Truth and Proof: Kurt Gödel and the Foundations of Mathematics*, University of Edinburgh, 2006.

Semantics for Vagueness vs. Logics for Vagueness: The Case of Fuzzy Logics. *The Challenge of Semantics (European Science Foundation Exploratory Workshop)*, Vienna, 2004.

Hilbert's Epsilon Calculus and Epsilon-Substitution Method. *Hilbert Workshop, Japanese Society for the Philosophy of Science*, Keio University, Tokyo, 2002.

Hilbert's Project of Consistency Proofs in the 1920s. *Logic and the Foundations of the Exact Sciences: Hilbert's Heritage*, Berne, Switzerland, 2001.

The Practice of Finitism. *Hilbert Workshop*, Institut d'Histoire et Philosophie des Sciences et Techniques, CNRS/Université Paris I, 2000.

The Practice of Finitism. *History of Logic*, University of Helsinki, 2000.

The Reach of Finitism. *Collegium Logicum: Proof Theory*, Vienna, 1999.

The Historical Significance of Consistency Proofs. *The Development of the Foundations of Mathematics in the 1920s and 30s*, Institute Vienna Circle, Vienna, 1999.

Bernays' Early Contributions to Logic. *The Development of Modern Logic*, University of Helsinki, 1998.

Uniform Deduction Systems for Finite-valued First-Order Logics. *Eighth European Summer School in Language, Logic, and Information*, Prague, 1996.

A Software Package for Axiomatizing Finite-Valued First-Order Logics. *Seventh European Summer School in Language, Logic, and Information*, Barcelona, 1995.

Steinhardt on Variables. *Society for the Study of the History of Analytic Philosophy Annual Meeting*, Denver, 2016.

General Natural Deduction Rules and General Lambda Calculi. *Annual Meeting of the Association for Symbolic Logic*, University of Connecticut, Storrs, 2016.

Substitution, Consequence, and Proof. *Society for Exact Philosophy*, Hamilton, ON, 2015.

The Epsilon Calculus and Non-Classical Logics. *Nonclassical Proofs: Theory, Applications, and Tools*, Vienna, 2014.

The Place of Logic in Computer Science Education. *Logic Colloquium*, Vienna, 2014.

Carnap and Logic in the 1920s and 1930s. Montréal, 2014.

The Epsilon Calculus and Non-Classical Logics. *Winter Meeting of the Association for Symbolic Logic*, New Orleans, 2013.

Carnap, Tolerance, and the Foundational Debate in Mathematics. *International Congress on Logic, Philosophy, and Methodology of Science*, Nancy, France, 2011.

Ayer and the Vienna Circle. *Western Canadian Philosophy Association*, University of Calgary, 2010.

Carnap between Logicism and Formalism. *History of Philosophy of Science 2006*, Paris, 2006.

Complexity of Elimination Procedures in the Epsilon Calculus. *Logic Colloquium*, Athens, Greece, 2005.

Algebraic Semantics for Logics of Vagueness. *Society for Exact Philosophy*, University of Toronto, 2005.

Logic Instruction and Philosophy Graduate Training. *Spring Meeting of the Association for Symbolic Logic*, San Francisco, 2005.

Gödel's First Incompleteness Theorem and Detlefsen's Hilbertian Instrumentalism. *Logic Colloquium*, Turin, Italy, 2004.

Axiomatizability of First-Order Gödel Logics. *Logic Colloquium*, Turin, Italy, 2004.

Finite-Valued Approximations of Propositional Logics. *Foundational Methods in Computer Science*, Kananaskis Field Station, University of Calgary, 2004.

Gödel's First Incompleteness Theorem and Mathematical Instrumentalism. *Midwest Philosophy of Mathematics Workshop*, University of Notre Dame, 2003.

Characterization of the Axiomatizable Prenex Fragments of First-Order Gödel Logics. *33rd International Symposium on Multiple Valued Logic*, Tokyo, 2003.

Hilbert's `Verunglückter Beweis' and the Epsilon Theorem. *Spring Meeting of the Association for Symbolic Logic*, Seattle, 2002.

Quantified Propositional Intuitionistic Logic on Trees is Decidable. *Logic Colloquium*, Vienna, 2001.

The Syntax-Semantics Distinction and Hilbert's `No Ignorabimus'. *History of Philosophy of Science*, Vienna, 2000.

Hilbert, Bernays, and some Fundamental Advances in Logic, 1918-1923. *New Orleans*, , 1999.

Infinite-valued Gödel Logics. *Annual Meeting of the Association for Symbolic Logic*, Unversity of California, San Diego, 1999.

Hilbert's Finitist Numbers. *1997 Stanford–Berkeley Philosophy Conference*, Stanford University, 1997.

Generalizing Theorems in Real Closed Fields. *Winter Meeting of the Association for Symbolic Logic*, San Francisco, 1995.

Approximating Propositional Calculi by Finite-Valued Logics. *24th International Symposium on Multiple-Valued Logic*, Boston, 1994.

Systematic Construction of Natural Deduction Systems for Many-Valued Logics. *23rd International Symposium on Multiple-Valued Logic*, Sacramento, 1993.

Comments on Patricia Blanchette: Models from Geometry to Logic. *50th Chapel Hill Philosophy Colloquium*, University of North Carolina, Chapel Hill, 2016.

Comments on Bryson Brown and Andrew Tedder: Multiple Conclusions. *Annual Meeting of the Western Canadian Philosophy Association*, University of Lethbridge, 2012.

Comments on Victor Rodych: Who is Wittgenstein's Worst Enemy?. *Annual Meeting of the Western Canadian Philosophy Association*, University of Lethbridge, 2003.

Comments on Jonathan Seldin: On Normalizing Disjunctive Intermediate Logics. *Annual Meeting of the Western Canadian Philosophy Association*, University of Calgary, 2002.

Comments on Thomas Hofweber: Proof-Theoretic Reduction as a Philosopher's Tool. *Stanford-Berkeley Philosophy Conference*, Stanford University, 1999.

Rudolf Carnap and the Logic of Tolerance. *Calgary Institute for the Humanities*, University of Calgary, 2016.

Hilbert's Program and the Foundations of Mathematics. *Department of Mathematics*, University of Calgary, 2002.

Rudolf Carnap and the Logic of Tolerance. *Calgary Institute for the Humanities Public Lecture*, University of Calgary, 2016.

Alan Turing and the Decision Probem. *Alan Turing Centenary Lecture Series*, University of Calgary, 2012.

The Decision Problem and the Development of Metalogic. *Calgary Peripatetic Research Group in Logic and Category Theory*, University of Calgary, 20084.

Logic, Paradox, and Misplaced Optimism: How Early 20th Century Philosophy of Mathematics Paved the Way for Modern Computer Science. *Calgary Institute for the Humanities Public Lecture*, University of Calgary, 2007.

What is a Logic of Vagueness? And How do we Figure Out Which One is Right?. *Vendler Research Group in Logic and Language,*, University of Calgary, 2005.

Mathematical Instrumentalism and Gödel's Incompleteness Theorems. *History and Philosophy of Science Research Group*, University of Calgary, 2004.

Introduction to the Epsilon Calculus II. *Calgary Peripatetic Research Group on Logic and Category Theory*, University of Calgary, 2003.

Introduction to the Epsilon Calculus I. *Calgary Peripatetic Research Group on Logic and Category Theory*, Unversity of Calgary, 2003.

Hilbert, Bernays, and the History of Logic. *History and Philosophy of Science Research Group*, University of Calgary, 2002.

Intuitionistic Fuzzy Logic and other Gödel Logics. *Calgary Peripatetic Research Group on Logic and Category Theory*, University of Calgary, 2002.

Instrumentalism in Mathematics. *Philosophy Colloquium*, University of California, Berkeley, 1999.

Finitistic Consistency Proofs. *Working Group on History and Philosophy of Mathematics and Logic*, University of California, Berkeley, 1998.

Completeness before Post: Hilbert and Bernays on Propositional Logic, 1917–18. *Working Group on History and Philosophy of Mathematics and Logic*, University of California, Berkeley, 1998.