Committed to Truth: Celebrating Cezary Cieśliński’s 60th birthday

ABOUT

On 19 September 2026, we will be meeting at the Faculty of Philosophy, University of Warsaw to celebrate Cezary Cieśliński’s 60th birthday. On this occasion, senior and junior researchers will exchange ideas on topics Prof. Cieśliński has contributed to.

KEYNOTE SPEAKERS

– Ali Enayat (University of Gothenburg)
– Volker Halbach (University of Oxford)
– Leon Horsten (University of Konstanz)
– Albert Visser (University of Utrecht)

CALL FOR REGISTRATION

Participation is possible either in person or online via Zoom. If you wish to participate, please complete the registration form available here. 

Important: The Zoom link will be made available only to the registered participants.

PROGRAMME

10 – 11 Albert Visser (Utrecht University) — Incompleteness through a Boolean Lens

11 – 11.30 Coffee break

11.30 – 12.00 Michael Sheard (St. Lawrence University)  — Hidden in Plain Sight: Toward a Canonical Class of Models of FS

12.00 – 13.00 Volker Halbach (Oxford University) — Reflection, Implicit Commitment, and Truth

13.00 – 15.00 Lunch break

15.00 – 16.00 Ali Enayat (Gothenburg University) — Tarskian Truth and Set Theory

16.00 – 16.30 Daichi Hayashi (University of Bristol)  — On (Co-)Necessitation in Intuitionistic Kripke-Feferman

16.30 – 17.00 Coffee break

17.00 – 17.30 Pietro Brocci (Scuola Normale Superiore)– Cyclic Positive Disquotational Truth

17.30 – 18.30 Leon Horsten (University of Konstanz) — A few Episodes in the History of Epistemic Reflection

ORGANIZING COMMITTEE

Mateusz Łełyk • Luca Castaldo • Michał Gil Sanchez • Maciej Głowacki • Piotr Gruza • Katarzyna Kowalik • Konstantinos Papafilippou • Bartosz Wcisło • Michał Wrocławski • Matteo Zicchetti

FURTHER INFORMATION
The 45th edition of JAF (Journées sur les Arithmétiques Faibles – Weak Arithmetics Days) will take place on 16⁠–⁠18 September 2026 in Warsaw. Details on the webpage https://jaf45warsaw.wfz.uw.edu.pl.

19 September 2026
Warsaw, Poland
https://cieslinskibc.wfz.uw.edu.pl
cieslinski.birthday@uw.edu.pl