Degree

• PhD (Philosophy)（Keio University 2010-03）

Research History

Education

Awards

• Special Committee Award, the 29th Annual Meeting of The Association for Natural Language Processing（2023-03）
• The Japan Association for Philosophy of Science Research Award（2014-11）
• The Japan Association for Philosophy of Science Research Award（2009-10）

Others

• Workshop: “Self and Infinity” (Kyoto University) (co-organizer)
• Workshop: “Self and Infinity” (Husserl Archive, Paris) (co-organizer)
• Second Workshop on Mathematical Logic and its Applications (Kanazawa, the JSPS Core-to-Core Program "Mathematical Logic and its Applications") (co-organizer and program committe)
• WIAS Seminar "Type Theory and Proof Theory" (Waseda University)(co-organizer)
• WIAS Top Runners' Lecture Collection "Proof Theory and Computation (1) and (2)" (Waseda University) (co-organizer)
• WIAS "Philosophy of Logic" Workshop: Meaning, Proof, and Inference （Waseda University）(organizer)
• Workshop “Logic and Philosophy of Mathematics" (Keio University and Waseda University) (co-organizer)
• 高等研究所セミナー 「Logic and Game Theory」(Waseda University) (co-organizer)
• Workshop “Philosophy of logic and Mathematics -- Towards Philosophy of Proofs" (Keio University) (co-organizer)
• WIAS Workshop ``Philosophy of Logic Workshop: Kant, Husserl, and Linear Logic" (Waseda University) (organizer)
• WIAS Seminar "Reverse Mathematics in Commutative Ring Theory" (Waseda Univeristy) (organizer)
• WIAS Philosophy of Mathematics and Logic Seminar (Waseda University) (organizer)
• "Philosophy of Mathematics and Proof Theory" Workshop (Keio University) (co-organizer)
• WIAS Top Runners’ Lecture Collection "Computations, Proofs, and Intuitions: A Workshop on Philosophy of Mathematics" (Waseda University) (organizer)
• WIAS Seminar "Phase transitions in logic: combinatorics and provability" (Waseda University) (organizer)
• GCOE Logic Seminar Naohi Eguchi (Keio University) (co-organizer)
• Philosophy of Mathematics Seminar: Hiroshi Kaneko and Yuta Takahashi (Keio University) (co-organizer)
• Lecture by Professor Richard Zach : "The Epsilon Calculus" (Keio University) (co-organizer)
• Internaional Workshop "Proof Theory and Philosophy" (Keio University) (co-organizer)
• Philosophy of Logic and Mathematics Seminar: Ryo Ito and Takuro Ohnishi (Keio Univeristy) (co-organizer))
• Lecture by Professor Bob Hale "What is absolute Necessity?" (Keio University) (co-organizer)
• Arguing for contradictions: dialectical gamesi n Plato's dialogues (Keio University) (co-organizer)
• Lectures by Professor Akihiro Kanamori and Professor Juliet Floyd (Keio University) (co-organizer)
• Lecture by Dr. Shunsuke Yatabe (Keio University) (co-organizer)
• A Proof Theory Workshop with Lecture Series by Grigori Mints (Keio University) (co-organizer)

Papers

• Schwichtenberg’s Style Analysis of Parameter-Free Fragments of Girard’s System F（2025-04）
• A Note on Feferman and Takeuti II: Philosophical Perspectives on Inductive Definitions（2025-03）
• Annotation of Japanese Discourse Relations Focusing on Concessive Inferences（2024-05）
• A Note on Feferman and Takeuti: Their Thoughts on Predicativity and Finitism（2024-03）
• Annotations of Discourse Relations in Japanese Focusing on Inferential Relations of Contradictory Conjunction (in Japanese)（2023-03） [Othres link]
• Foundations of Mathematics a la Kyoto School: from Nishida to Takeuti via Suetsuna（2023-03） [Othres link]
• Logic of Alternative-I（2022-11） [DOI] [Othres link]
• Takeuti's well-odering proofs revisited（2021-03） [Othres link]
• Takeuti’s proof-theory in the context of the Kyoto school（2019-10） [Othres link]
• A Formalization of Brouwer's Argument for Bar Induction（2018-07） [DOI]
• An Interpretation of Brouwer’s Argument for Bar Induction via Infinitary Proof Theory（2018） [DOI]
• Contentual and Formal Aspects of Gentzen's Consistency Proofs（2017-12） [Othres link]
• An Ordinal-Free Proof of the Complete Cut-Elimination Theorem for Π11-CA + BI with the ω-rule（2017-05） [Othres link]
• Strong normalization for the parameter-free polymorphic lambda calculus based on the Omega-rule（2016-06） [DOI]
• An Extension of the Omega-Rule（2016-05） [DOI]
• Some Remarks on Toshihiro Suzuki's "Phänomenologie der Mathematik" (in Japanese)（2015-04） [Othres link]
• Brouwer’s Argument for the Bar Induction Revisited（2014）
• Towards understanding Brouwer's fundamental assumption（2013） [CiNii Research (CiNii Articles)] [CiNii Books] [Othres link]
• Reading Gentzen’s Three Consistency Proofs Uniformly（2013） [DOI] [CiNii Research (CiNii Articles)] [CiNii Books] [Othres link]
• Proof Theory as an Analysis of Impredicativity(New Developments in Logic: Proof-Theoretic Ordinals and Set-Theoretic Ordinals)（2012） [DOI] [CiNii Research (CiNii Articles)] [CiNii Books] [Othres link]
• An Extension of the Iterated Omega-Rule（2011）
• Gentzen's First Consistency Proof Revisited（2010）
• Tait's Conservative Extension Theorem Revisited（2010） [DOI]
• An Ordinal-Free Proof of the Cut-elimination Theorem for a Subsystem of \Pi^1_1-Analysis with omega-rule（2009） [CiNii Research (CiNii Articles)] [CiNii Books] [Othres link] [Othres link]
• Proof-Theoretic Investigations of Type Theory and Subsystems of Second-Order Arithmetic（2009） [Othres link]
• Takeuti's Reduction and Impredicativity（2009）
• On a Relationship between Goedel's Second Incompleteness Theorem and Hilbert's Program（2009） [DOI] [CiNii Research (CiNii Articles)] [CiNii Books] [Othres link]
• Hilbert and Goedel（2004）

Misc

• Towards proof-theoretic semantics for second-order logic（2024-10）
• Intuition in philosophy of mathematics（2024-10）
• The logic of presence（2024-05）
• Husserl and Schroeder（2023-10）
• Toward an Alternative to the Master-Slave Model: A View from East Asia（2022-11）
• On Gaisi Takeuti's Philosophy of Mathematics (abstract)（2019-12）
• "Proofs as Programs" Revisited (abstract)（2019-07）
• The Upperbound of the Length of the Reductions in a Subsystem of Girard's F（2018）
• A uniform idea behind Gentzen’s three consistency proofs (abstract)（2016-09）
• Proof-Theoretic Analysis of Brouwer's Argument of the Bar Induction (abstract)（2015-03）
• An Interpretation of Brouwer's Argument for Bar Theorem via Infinitary Proof Theory (abstract)（2013）
• Complete Cut-Elimination Theorem for Ω-Rule (abstract)（2012）
• これからの数学・論理学の哲学に向けて（2012）
• An Ordinal-Free Proof of the Cut-elimination Theorem for Π11-CA with ω-rule (abstract)（2011）
• 書評：『ゲーデルの２０世紀の論理学③不完全性定理と算術の体系』（田中一之編，東京大学出版会）（2009） [CiNii Research (CiNii Articles)] [CiNii Books] [Othres link]

Presentations

• Annotation of Japanese Discourse Relations Focusing on Concessive Inferences（2024-05）
• Intuition in Kant, Fichte and Nishida（2024-04）
• Takeuti on finite and infinite sets（2023-03）
• Annotations of Discourse Relations in Japanese Focusing on Inferential Relations of Contradictory Conjunction (in Japanese)（2023-03）
• Towards Proof-Theoretic Semantics for Second-Order Logic（2023-03）
• Exploring the need for an alternative to the "master-slave" model in robot ethics inspired by Navon's standpoint (in Japanese)（2022-07）
• ELSI Research on Smart Cities: Focusing on Concrete Examples (in Japanese)（2022-05-30）
• From an East Asian View of the Self to a Society with Multi-Layered Values (in Japanese)（2022-03-13）
• Husserl and Schroeder (in Japanese)（2021-05）
• Takeuti’s finitism in the context of the Kyoto school（2020-03）
• Takeuti’s argument of the well-foundedness of ordinals up to the epsilon_0（2020-02）
• Takeuti’s finitism in the context of the Kyoto school（2020-02）
• Takeuti’s Finitism Revisited（2020-02）
• On Gaisi Takeuti's philosophy of mathematics（2019-08-12）
• On Gaisi Takeuti's philosophy of mathematics（2019-08-07）
• 飯田氏の論理学・数学の哲学をめぐって（2019-03）
• On Takeuti's Finitism（2019-02）
• Takeuti’s Finitism Revisited（2019-02）
• Disagreement on Brouwer’s Argument for Bar Induction（2019-01）
• Towards a new development of formalism: Gaisi Takeuti's philosophy（2018-11）
• Cut-elimination methods by Gentzen and Schuette（2018-09）
• "Proofs as Programs" Revisited（2018-07）
• "Proofs as Programs" Revisited（2018-02）
• "Proofs as Programs" Revisited（2018-01）
• Gentle Introduction to the Omega-Rule: Part II（2017-09）
• A Formalization of Brouwer's Argument for Bar Induction（2017-07）
• Gentle Introduction to the Omega-Rule: Part I（2017-03）
• Brouwer's Argument of Bar Induction Revisited（2017-02）
• Strong normalization for the parameter-free subsystem of System F based on the Omega-rule（2017-02）
• Opening Remarks（2017-01）
• On Brouwer’s argument of bar induction（2017-01）
• Strong normalization for the parameter-free polymorphic lambda calculus based on the Omega-rule（2016-11）
• Contentual and Formal Aspect of Gentzen's Consistency Proofs（2016-10）
• Strong normalization for the parameter-free polymorphic lambda calculus based on the Omega-rule（2016-09）
• Strong normalization for the parameter-free polymorphic lambda calculus based on the Omega-rule（2016-06）
• ヒルベルト，ブラウワーからゲンツェンへ（2015-11）
• Opening Remarks（2015-09）
• Some Results in Proof-Theory for Pi11-CA（2015-09）
• A Uniform Idea behind Gentzen's Three Consistency Proofs（2015-08）
• A Constructive Justification of Brouwer’s Bar Induction（2015-08）
• An Invitation to Intuitionism（2015-06）
• An Interpretation of Brouwer's Argument of the Bar Induction via Infinitary Proof Theory（2015-03）
• Brouwer's Argument of the Bar Induction Revisited（2015-02）
• Guest Commentator: “Logical Inference and Proofs” Franco- Japanese Workshop（2015-01）
• Extension and Application of the Ω-rule（2014-12）
• Reading Brouwer Proof-Theoretically（2014-12）
• Proof-Theoretic Analysis of the Bar Induction（2014-12）
• 特別企画 鈴木俊洋『数学の現象学』合評会におけるコメンテイター（2014-08） [Othres link]
• Proof-Theoretic Analysis of Brouwer’s Argument of the Bar Induction（2014-08）
• An Introduction to Proof Theory of First- Order Arithmetic（2014-08）
• Proof-Theoretic Analysis of Brouwer’s Argument of the Bar Induction（2014-07）
• ブラウワーの基本仮定について（2014-06） [Othres link]
• Invited Commentator at "Philosophy of Mathematics and Logic” Meeting（2014-02）
• Brouwer’s Proof of the Bar Induction Revisited（2014-02）
• An Interpretation of Brouwer’s Argument for the Bar Induction via Infinitary Proof Theory（2013-08） [Othres link]
• Proper Explanation of Brouwer's Fundamental Assumption（2013-03）
• Brouwer’s proof of the bar induction revisited（2013-03）
• Cut-Elimination for Pi^1_1-CA（2013-02）
• 余帰納法の証明論への応用：Ω 規則の観点から（2012-11）
• An extension of the Ωμ+1-rule（2012-07）
• 形式主義の再検討に向けて（2012-02）
• Ω 規則の拡張について（2011-11）
• Complete Cut-Elimination Theorem for Ω-Rule（2011-07）
• 非可述性の分析としての証明論（2011-06）
• 順序数を用いない証明論について（2011-02）
• ゲンツェンの無矛盾性証明再訪（2010-11）
• Finite Notations for Ωμ+1-rule（2010-07）
• Introduction to Proof Theory for Impredicative Systems (Tohoku University)（2010-06）
• An Interpretation of Takeuti’s Reduction（2010-03）
• Finite Notations for Ωμ-rule（2010-03）
• 証明論的手法による二階論理の論理哲学的研究（2010-02）
• 竹内の還元法と非可述性について（2009-11）
• An Ordinal-Free Proof of the Cut-Elimination Theorem for Pi^1_1-CA with ω-rule（2009-06）
• 証明論的手法による二階論理の論理哲学的探究（2009-03）
• An ordinal-free proof of the cut-elimination theorem for Pi^1_1-analysis with ω-rule（2009-02）
• 順序数を用いないカット消去定理の証明について（2008-11）
• An ordinal-free proof of the cut-elimination theorem for Pi^1_1-analysis with ω-rule（2008-11）
• 非可述な体系のカット消去定理の順序数を用いない証明について（2008-09）
• An ordinal-free proof of the cut-elimination theorem for Pi^1_1- analysis with ω-rule（2008-05）
• On a relationship between cut-elimination proofs by W. Tait and W. Buchholz（2008-05）
• テイトの保存拡大定理について（2007-12）
• テイトの保存拡大定理について（2007-11）
• 第二不完全性定理とヒルベルト・プログラム（2007-06）

Books and Other Publications

• Gendai Ronrigaku Jiten (Encyclopedia of Modern Logic)（2025）
• Doitsu Tetsugaku・Shiso Jiten (Encyclopedia of German Philosophy and Thoughts)（2025）
• Yokuwakaru Tetsugaku and Shisou (textbook on philosophy)（2019-04）

Works

Research Projects

Media Coverage

Industrial Property Rights

Professional Memberships

• Philosophy of Science Society, Japan
• Annals of the Japan Association for Philosophy of Science
• Association for Symbolic Logic

Committee Memberships

Teaching Experience

• Topics in History and Philosophy of Science
• 哲学特殊講義
• 論理学入門（文学部設置）
• Topics in Philosophy and Religion
• Introduction to Logic
• 論理的思考のすすめ
• ことばと論理Ａ・B
• 哲学倫理学特殊
• Symbolic Logic II
• 情報数理学続論
• 数学の哲学
• 哲学A
• Symbolic Logic I
• Introduction to Logic A・B
• Advanced Topics in Philosophy of Science
• 論理学
• 哲学専門講義（英米哲学／現代哲学）
• 論理学入門（理工学部設置）

Social Contribution

Academic Contribution