Welcome to Susumu CATO's website

Professor, Institute of Social Science, University of Tokyo

Email: susumu.cato[at]gmail.com (replace [at] with @)

Correspondence Address

Institute of Social Science, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033

Research Fields

• Social Choice Theory

• Political Philosophy (distributive justice & population ethics)

• Politics, Philosophy, and Economics (PPE)

• Welfare Economics

• Organizational Economics

• Industrial Organization

News

• Jan 21, 2025: Co-organizing an international workshop

  • Title: Inclusiveness and Sustainable Development

  • Venue: Venue: Sanjō Conference Hall, University of Tokyo

    • 11:50 PM - 12:50 PM: Ayako Ozawa (DBJ) and Tatsufumi Aoyama (DBJ)

    • 12:50 PM - 1:00 PM: Welcoming and Opening Remarks

      • Susumu Cato (UTokyo) and Jungmin Park (SNU, Department of Social Welfare & PPE)

    • 1:00 PM - 2:20 PM: Session 1 (Sanjō Conference Hall, Two speakers, 40 minutes each)

      • Eric Weese (UTokyo, Institute of Social Science): Creative Destruction in the European State System: 1000-1850 (With David Schonholzer)

      • Hyunwoo Hong (CNU, Department of Economics): Climate Justice: Historical Accountability vs. International Paretianism

    • 2:20 PM - 2:40 PM: Coffee/Tea Break

    • 2:40 PM - 4:00 PM: Session 2 (Sanjō Conference Hall, Two speakers, 40 minutes each)

      • Biung-Ghi Ju SNU, Department of Economics & PPE): Adam Smith Theorem: Justice Leads Prosperity

      • Ayumi Igarashi (UTokyo): Fair allocation of indivisible items under category constraints

    • 4:00 PM - 4:10 PM: Closing Remarks

  • Hosted by

    • Economics Program in Seoul National University (main organizer) 

    • "Methodology of Social Sciences" project of Institute of Social Science, University of Tokyo (co-organizer) 

    • Research Institute of Capital Formation, Development Bank of Japan. (co-organizer)

• Jan 28, 2025: A new paper has been accepted.

  • Title: Rational Incompetence of Voters

  • Journal: Journal of Ethics and Social Philosophy

• Jan 30, 2025: 2nd Workshop on Social Choice Theory 

• Feb 7, 2025: A new paper has been accepted.

  • Title: Positional Conditional Egalitarianism 

  • Journal: Inquiry: An Interdisciplinary Journal of Philosophy

  • Co-author: Ken Oshitani

• Feb 13: A paper has been accepted: 

  • Title: Ex-post approaches to prioritarianism and sufficientarianism

  • Journal: Theoretical Economics

  • Co-authors: Matthew D. Adler, Walter Bossert, and Kohei Kamaga

• March 6, 2025: ISS Analytical Philosophy Workshop

Program：
10:00-10:15 Opening Remarks

10:15-11:15 Kumie Hattori (University of Tokyo)

• Title Retroactive Blame in Law

• Chair Kiichi Inarimori

11:15-12:15 Joel A. Van Fossen (Hosei University)

• Title Appreciation, Inquiry, and Deliberation: Exploring the Structure of Three Processes [joint work with Daniel Star]

• Chair Ken Oshitani

12:15-13:45 Lunch Break

13:45-14:45 Jeroen Hopster (Utrecht University)

• Title: Climate Disruption, Legitimate Expectations, and the Value of Stability

• Chair Arata Matsuda

14:45-15:00 Coffee Break

15:00-16:00 Susumu Cato (University of Tokyo)

• Title: What the Demands of Sustainability Can(not) Be. [joint work with Katie Steele]

• Chair Clara Brigitta Riegler

16:00-17:00 Kengo Miyazono (Hokkaido University)

• Title A Non-Cognitivist Account of Moral Responsibility and Free Will [joint work with Kiichi Inarimori]

• Chair Susumu Cato

• May 4: A paper has been accepted: 

  • Title: Effects of Sanctions on Criminalized Prostitution Markets

  • Journal: Review of Law & Economics

  • Co-author: Ken Yahagi

• June 12, 2025: ISS Analytic Philosophy Workshop

  • • 13:00-14:00: Tatsuya Yoshii (Kyoto University) & Jun Otsuka (Zen University) “A Categorical Solution to the Grue Paradox” Chair: TBA

    • 14:10-14:50: Susumu Cato (University of Tokyo) “Revisiting the Okasha-Morreau Problem of Theory Choice” Chair: TBA

    • 15:20-16:20: Eddy Keming Chen (University of California, San Diego) “Exchangeability and Algorithmic Randomness: A New Proof of the Principal Principle” Chair: TBA

    • 16:30-17:30: Alan Hájek (Australian National University) “A Chancy Theory of Counterfactuals” Chair: Masaki Ichinose (Musashino University)

• June 26, 2025: A paper has been accepted: 

  • Title: An axiomatic characterization of the proportional threshold methods: A geometric approach

  • Journal: Social Choice and Welfare

  • Co-authors: Stéphane Gonzalez, Eric Rémila, Philippe Solal

• July 5, 2025: Organizing a session at Society for the Advancement of Economic Theory（SAET） 

  • Session Title: Well-Being and Collective Decision- Making 

  • Vanue: Ischia, Italy at the Hotel Continental Terme

  • Speakers: 

    • Gregory Ponthiere: Stoicism and the Value of Life

    • Kohei Kamaga [With Walter Bossert and Susumu Cato]: Population ethics with thresholds

    • Stéphane Zuber [With Johan E. Gustafsson and Dean Spears]: New Characterization of Expected TotalUtilitarianism

    • Susumu Cato [With Walter Bossert and Kohei Kamaga]: Decisive coalitions and scoring rules

• July 9, 2025: A paper has been accepted:

  • Title: Welfarism and Continuity in Ethical Theory: A Formal Comparision of Prospect Utilitarianism vs. Sufficientarianism

  • Journal: Economics and Philosophy

  • Co-author: Hun Chung 

• Sept 2:  A talk at Komaba, UTokyo 

  • Title: A crash course in formal axiology

  • Date & Time: Tuesday, September 2, 15:00–17:00

  • Venue: Collaboration Room 1, 4th Floor, Building 18, Komaba I Campus, University of Tokyo

  • Organizer: Akira Inoue

  • Language: Japanese

• Sept 8: Tokyo Social Choice Workshop

  • Venue: Sophia University, Yotsuya Campus. 2nd floor, Bldg. 6, Room 203.10:35–10:40 

  • Program

    • Opening Remarks

    • 10:40–11:20 Noriaki Kiguchi (Kyoto University, JSPS) "Collective State Spaces" (joint with Takashi Hayashi and Norio Takeoka)

    • 11:30–12:10  Shinpei Noguchi (Hitotsubashi University) "An Axiomatization of Inequality Averse Preferences with Egalitarian Concerns"

    • 14:00–14:40  Keisuke Bando (Keio University) "Stable matching under inconsistent choice functions"

    • 14:50–15:30  Ken Oshitani (Waseda University)"Contractualism, Aggregation, and Impersonal Value"

    • 16:15–16:55  Kazuya Kikuchi (Tokyo University of Foreign Studies)“Self-Stable Weighted Majority Rule”

    • 16:55–17:10  Discussion session for future workshops

• Sept 17, 2025: A paper has been accepted:

  • Title: The structure of critical sets 

  • Journal: Philosophical Studies

  • Co-authors: Walter Bossert and Kohei Kamaga

• Sept 19-20, 2025: A talk at Axiology Workshop in Montreal

  • Title: Population ethics with thresholds

  • Date: September 19

  • Venue: Room 160, Arts Building, McGill University

  • Organizer: Iwao Hirose

• Oct 10, 2025: A talk at Paris 1

  • Title: "What the Demands of Sustainability Can(not) Be" (joint work with Katie Steele)

  • Date: October 19

• Oct 28, 2025: Annual John Stuart Mill 2025: VU Amsterdam, John Stuart Mill College

  • Title: Social Choice and Moral Dilemmas: An Axiomatic Exploration

  • Venue: VU Amsterdam, John Stuart Mill College

• Nov 4, 2025: Tokyo Axiology Workshop

  • Venue: Institute of Social Science, University of Tokyo

  • Program

    • Yoshiki Yoshimura

    • Ken Oshitani

    • Andrew Reisner

  • Organizers: Susumu Cato and Ken Oshitani

• Nov 15, 2025: A paper has been accepted: 

  • Title: A formal theory of Robert Nozick's framework for utopia

  • Journal: Noûs

  • Coauthor: Hun Chung

• Nov 19, 2025: the 9th Spain-Japan Meeting on Economic Theory 

  • Title: Decisive Coalitions and Scoring Rules

  • Venue:  Waseda University

  • Co-author: Walter Bossert and Kohei Kamaga)

• Nov 21, 2025: the 172nd meeting of the Osaka Workshop on Economics of Institutions and Organizations

  • Title: Long-run Evolution of Gini Inequality in Japan, 1722–1840

  • Venue: Online

  • Co-author: Masaki Nakabayashi

• Dec 11, 2025: ISS Analytic Philosophy Workshop: The Current Issues in Metaethics

  • Venue: Institute of Social Science, University of Tokyo

  • Program

    • 13:00-14:00 Ryo Chonabayashi (Soka University) “Moral Abductivism: Some Worries and Response to Them”  Chair: Susumu Cato (University of Tokyo) 

    • 14:10-15:10 Peter Shiu-Hwa Tsu (National Chung Cheng University) “Rationality, Embeddedness, and Imaginary Cases in Ethics” Chair: TBA 

    • 15:20-16:20 Bart Streumer (Groningen University) “How to Be a Self-Effacing Consequentializing Quasi-Realist” Chair: Iwao Hirose (McGill University)

  • Organizers: Susumu Cato and Iwao Hirose

• Dec 14, 2025: CAPE Lecture at Kyoto University

  • Lecture 1: Binary Relations and Axiological Theories

  • Lecture 2: Uncertainty and Population Ethics

  • Lecture 3: How to Write Formal Papers

• January 8, 2026: A paper has been accepted: 

  • Title: What the demands of sustainability can(not) be

  • Journal: Ethics

  • Co-author: Katie Steele 

• February 8, 2026: A paper has been accepted: 

  • Title: Discounting Offenders' Private Benefits

  • Journal: American Law and Economics Review

  • Co-author: Ken Yahagi 

• March 31, 2026: A paper has been accepted

  • Title: Weak Independence is sufficient for making weak superiority collapse into strong superiority

  • Journal: Journal of Ethics and Social Philosophy

• April 29, 2026: A paper has been accepted

  • Title: The dilemma between repugnancy and sadism extends beyond Critical-Level Utilitarianism

  • Journal: Economics and Philosophy

  • Co-author: Geir B. Asheim

• May 6, 2026: A paper has been accepted: 

  • Title: Quasi-transitive and Suzumura consistent rationalizing relations

  • Journal: Theory and Decision

  • Co-authors: Walter Bossert, and Kohei Kamaga

• June 6, 2026: A paper has been accepted: 

  • Title: Do updates of group-level and individual-level information of ethnic minority applicants mitigate statistical discrimination in hiring?

  • Journal: Social Forces

  • Co-author: Akira Igarashi (first author)

• June 2026: 

  • "When Liberty Dominates Patterns: A Welfare Comparison of Political Regimes under Incomplete Contracts" (with Hun Chung & Jacob Watkins-Strand) (Won 1st Prize for the “Does Liberty Upset Patterns?” essay competition, University of Fribourg)

• June 19, 2026: A paper has been accepted: 

  • Title: Filters in abstract aggregation with infinite sequences of signals

  • Journal: Mathematical Social Sciences Mathematical Social Sciences

  • Co-authors: Stéphane Gonzalez, Eric Rémila, and Philippe Solal

• July 4, 2026: 

• July 11-12, 2026: Hitotsubashi Summer Institute (HSI) 2026

  • Title: A New Argument for the Sufficientarian Approach to Intergenerational Justice (July 11)

  • Co-author: Katie Steele

• July 17, 2026: A paper has been accepted:  

  • Title: Collective responsibility and individual compensation

  • Journal: Homo Oeconomicus

• July 23 to July 25, 2026: The 18th Conference of the International Society for Utilitarian Studies (ISUS 2026)

  • Title: A New Argument for the Sufficientarian Approach to Intergenerational Justice (my talk is day 1)

  • Location: the Faculty of Law of the University of Macau

  • Co-author: Katie Steele

• July 26, 2026: Symposium: What Can Liberalism Do? 

  • Celebrating the Publication of Liberalism (University of Tokyo Press) Edited by Shigeki Uno, Susumu Cato, and Akira Inoue 

  • To mark the publication of Liberalism, we are pleased to host a symposium exploring its relevance today. The world today faces pressing challenges, including war, social division, and widening inequality. When people are divided not only by conflicting interests but also by values that are difficult to reconcile, what role can liberalism play in political and social life? What did liberalism mean to John Rawls, one of the leading political philosophers of the twentieth century? And what questions does his work raise for us today? We will welcome Professor Iwao Hirose to join the book’s editors and contributors in discussing the significance of liberalism and the challenges it faces today. Drawing on the themes explored in the book, the symposium will offer an opportunity to reflect on liberalism’s possibilities and limits and deepen our understanding of it. 

  • Date and Time: Monday, July 27, 2026, 15:00–17:00 

  • Venue: Center Meeting Room (Room 549), 5th Floor, Akamon General Research Building, Hongo Campus, The University of Tokyo 

  • Language: Japanese Admission: 

  • Comments by Iwao Hirose (McGill University) 15:20–15:35 

  • Remarks by the editors: Shigeki Uno, Susumu Cato, and Akira Inoue

  • Panel discussion - General discussion, audience Q&A, and closing remarks

• August 7, 2026: A paper has been published: 

  • Title: Sustained social mobility and the Kemeny rule, 

  • Edited Volume: F. Busetto, S. Ghosal, L.A. Julien and S. Tonin (eds.), Recent Developments in General Equilibrium, Game Theory, and Social Choice: A festschrift for Giulio Codognato, Springer, Cham.

  • Co-authors: Walter Bossert, and Kohei Kamaga

• August 8, 2026: A book will be forthcoming: 

  • Title: Arrow's Impossibility Theorem

  • Publisher: Cambridge University Press (Cambridge Elements in Decision Theory and Philosophy).

• September 13, 2026: A paper has been accepted: 

  • Title: Periodic Equity Prioritarianism

  • Journal: Utilitas:

  • Co-author: Anders Herlitz

• October 15, 2026: A seminer talk at Maastricht University

  • Title: A New Argument for the Sufficientarian Approach to Intergenerational Justice

  • Co-author: Katie Steele