Research

Understanding the logical structure of "agency" has long been my main interest. I study rational behavior by looking at how information and inference combine with the logical structure of an agent's preferences, reasons for these, and their dynamic changes. I also believe that rationality unfolds at its most vivid in multi-agent settings, and so I study the formal properties of social relations and social influence as these affect agents' belief formation, changing and convergence of opinions. In particular, I am also fascinated by agents' strategic interactions, and study them in the context of various concrete games. Finally, I am excited about differences and similarities across cultures, comparing patterns of reasoning from a logical and historical point of view. Through my research, I have the privilege of collaborating with colleagues and students from philosophy, mathematics, linguistics, computer science and AI, game theory and economics.

Preference Logic

Main themes: developing a reason-based approach to preferences; exploring the dynamics of preference change through various events of changing information, evaluation, or goals.

Books

Fenrong Liu: Reasoning about Preference Dynamics, Springer-Verlag, 2011. Series: Synthese Library, Vol. 354.
Fenrong Liu: Dynamic Preference Logic, Science Press: Beijing, 2010 (in Chinese)
Fenrong Liu: Changing for the Better: Preference Dynamics and Agent Diversity, Ph.D dissertation, ILLC, University of Amsterdam, 2008.

Selected Papers

Fenrong Liu and Leendert van der Torre: Preference Logic. Stanford Encyclopedia of Philosophy, to appear, 2025.
Natasha Alechina, Fenrong Liu, and Brian Logan: Efficient Minimal Preference Change. Journal of Logic and Computation, 28(8): 1715-1733, 2018.
Sven Ove Hansson and Fenrong Liu: From Good to Better. Using contextual shifts to define preference in terms of monadic value. In Alexandru Baltag and Sonja Smets eds., Trends in Logic, Outstanding Contributions: Johan F. A. K. van Benthem on Logical and Informational Dynamics, Springer, 2014.
Johan van Benthem, Davide Grossi and Fenrong Liu: Priority Structures in Deontic Logic. Theoria, Volume 80, Issue 2, pages 116-152, May 2014.
Fenrong Liu: A Two-Level Perspective on Preference. Journal of Philosophical Logic, 40(3): 421-439, 2011.
Fenrong Liu: Von Wright's "The Logic of Preference" Revisited. Synthese, 175(1): 69-88, 2010.
Dick de Jongh and Fenrong Liu Preference, Priorities and Belief, in T.Grune-Yanoff and S.O. Hansson eds, Preference Change: Approaches from Philosophy, Economics and Psychology, Theory and Decision Library, pp.85-108, 2009.
Johan van Benthem and Fenrong Liu: Dynamic Logic of Preference Upgrade. Journal of Applied Non-Classical Logic, 17(2): 2007.

Social Epistemic Logic

Main themes: introducing the role of social structure into philosophical logics of knowledge and action; the dynamics of belief formation over time in social networks; the interface of "high" and "low" rationality in social group processes.

Books

Fenrong Liu: Social Epistemic Logic, Tsinghua University Press, 2023 (in Chinese)

Selected Papers

Fenrong Liu and Dazhu Li: Ten-Year History of Social Network Logics in China. Asian Studies, 10(2), 121-146, 2022.
Fenrong Liu and Emiliano Lorini: Reasoning about Belief, Evidence and Trust in a Multi-agent Setting. PRIMA 2017: 71-89.
Fenrong Liu: A Logical Study of Social Network Structure and Dynamics of Agent's Knowledge, Philosophical Research, No.1, pp. 121-126, 2016
Fenrong Liu, Jeremy Seligman, and Patrick Girard: Logical Dynamics of Belief Change in the Community. Synthese, Volume 191, Issue 11, pp 2403-2431, 2014.
Jeremy Seligman, Fenrong Liu and Patrick Girard: Facebook and Epistemic Logic of Friendship, in Burkhard C. Schipper ed, Theoretical Aspects of Rationality and Knowledge Proceedings of the 14th Conference Chennai, India, 2013. pp.229-238.
Patrick Girard, Jeremy Seligman and Fenrong Liu: General Dynamic Dynamic Logic, in Thomas Bolander, Torben Brauner, Silvio Ghilardi, and Lawrence Moss, eds, Advances in Modal Logic, Volume 9, pp.239--260. College Publications, London, 2012.
Jeremy Seligman, Fenrong Liu and Patrick Girard: Logic in the Community, in M. Banerjee and A. Seth, editors, Proceedings of the 4th Indian Conference on Logic and its Applications,Volume 6521 of LNCS, pp. 178-188. Springer, 2011.

Logics for Games and Social Interaction

Main themes: designing games and game logics in tandem; exploring logical and computational aspects of bounded agents in games.

Books

Johan van Benthem and Fenrong Liu: Graph Games and Logic Design, Recent Development and Future Directions, to appear, 2025.

Selected Papers

Katsuhiko Sano, Fenrong Liu and Dazhu Li: Hybrid Logic of the Hide and Seek Game, Studia Logica, 2024. https://doi.org/10.1007/s11225-024-10149-7
Dazhu Li, Sujata Ghosh, Fenrong Liu and Yaxin Tu: A Simple Logic of the Hide and Seek Game, Studia Logica 111: 821-853, 2023
Johan van Benthem and Fenrong Liu: Graph Games and Logic Design, in F. Liu, H. Ono and J. Yu eds., Knowledge, Proof and Dynamics, Springer Nature: Singapore. pp. 125-146, 2020.
Chanjuan Liu, Fenrong Liu and Kaile Su: A Dynamic-Logical Characterization of Solutions to Sight-limited Extensive Games. Fundamenta Informaticae, 158(1-3): 149-169, 2018.
Fenrong Liu and Yanjing Wang: Reasoning about Agent Types and the hardest logic puzzle ever. Minds and Machines, 23(1): 123-161, 2013.
Fenrong Liu: Diversity of Agents and their Interaction. Journal of Logic, Language and Information,18(1):23-53, 2009.
Johan van Benthem, Sujata Ghosh and Fenrong Liu: Modelling Simultaneous Games in Dynamic Logic. Synthese, 165(2): 247-268, 2008.

History of Logic in China

Main themes: bringing the open methodology of modern logic to bear on historical studies; opening up new ways of letting historical texts and authors speak for themselves; monotonicity reasoning in logical history and current formal semantics.

Books

Fenrong Liu, Jeremy Seligman and Jincheng Zhai, eds., Handbook of Logical Thought in China, to appear, Springer and China Social Sciences Press.
Fenrong Liu and Jeremy Seligman, eds., The History of Logic in China: 5 Questions, Copenhagen: Automatic Press, 2015.

Selected Papers

Fenrong Liu and Zhiqiang Sun: The Zhou Puzzle: A Peek into Quantification in Mohist logic, to appear 2025.
Zhiqiang Sun and Fenrong Liu: The Inference Pattern Mou in Mohist Logic - A monotonicity reasoning view. Roczniki Filozoficzne (Annals of Philosophy), No. 4, pp.105-117, 2020.
Johan van Benthem and Fenrong Liu: New Logical Perspectives on Monotonicity, in Deng, D., Liu, F., Liu, M., Westerståhl, D. (eds) Monotonicity in Logic and Language. TLLM 2020. LNCS, Vol 12564. pp.1-12. Springer, Berlin, Heidelberg, 2020.
Fenrong Liu, Jeremy Seligman and Johan van Benthem: Models of Reasoning in Ancient China. Studies in Logic, Special Issue on the History of Logic in China, 4(3): 57-81, 2011.
Fenrong Liu and Jeremy Seligman: Chinese Logic and Chinese Philosophy: Reconstruction or Integration? The IIAS Newsletter 58 Autumn 2011.
Fenrong Liu and Jialong Zhang: New Perspectives on Mohist Logic. Journal of Chinese Philosophy, 37(4): 605-621, 2010.
Fenrong Liu and Wujin Yang: A Brief History of Chinese Logic, in Amitabha Gupta and Johan van Benthem eds., Journal of the Indian Council of Philosophical Research, Special Issue on Logic and Philosophy Today, Volume. 27, No.1, pp. 101-126, 2010.