Dov Gabbay Prize for Logic and Foundations 2025
The Dov Gabbay Prize for Logic and Foundations is an international research prize launched on the occasion of Professor Dov Gabbay's 77th birthday. This initiative honours the extraordinary and multi-faceted scientific and editorial work of Dov Gabbay, known in particular for editing an extensive collection of specialized Logic Handbooks, and a life dedicated to Logic.
2025 Awardee
The Jury of the Dov Gabbay Prize and the Initiative for Logic and Foundations have the great pleasure to announce the winner of the 2025 edition of this Prize, whose focus was Philosophical Logic:
Alexandru Baltag (ILLC, University of Amsterdam, NL)
Our Congratulations!
Statement of the Jury
Born in Rumania, after studying mathematics at the University of Bucharest, Baltag became a PhD student with Jon Barwise in Bloomington, with a thesis on non-wellfounded set theory and its foundations in infinitary modal logics. This started off his career in 1998 with a Best Paper Award for his paper 'STS: A Structural Theory of Sets' at the well-known conference Advances in Modal Logic.
Baltag's subsequent trajectory passed through the Department of Computer Science at the University of Oxford, where he spent 10 years as a tenured University Lecturer, before becoming an Associate Professor at the Institute for Logic, Language and Computation (ILLC) at the University of Amsterdam.
His academic work has been marked by several highlights. He is one of the authors of the seminal 1998 ‘BMS’ paper by A. Baltag, L. Moss and S. Solecki which introduced the paradigm of Dynamic-Epistemic Logic, a powerful extension of existing epistemic logics that can describe the precise information flow in a wide range of scenarios, something that did not exist before. Baltag has become the leading architect of this research program, whose applications continue to increase in number, starting out from philosophical topics in epistemology concerning knowledge change (e.g., those relating to the famous Fitch Paradox), belief revision, and subjective probability, but also reaching out to practical areas such as epistemic planning in AI. In recent years, together with Sonja Smets, he has extended this framework to deal with a wide range of topics in social epistemology and the social sciences about group behavior under information flow.
Typical for Baltag’s working style is the combination of philosophical interests and erudition with mathematical analysis of the logical systems produced in this way. This also shows in the next major line where he has become a leading figure.
In the last decade, Baltag has become one of the main movers in Epistemic Topology, the branch of formal epistemology which uses logical-topological models for analyzing age-old philosophical questions such as the Problem of Induction, and the issues posed by observation in the empirical sciences where measurements are approximate. Epistemic Topology follows earlier work by Steve Vickers and Kevin Kelly, but in Baltag’s work it has taken new directions. As just one example, his recent work with Nick Bezhanishvili and David Fernandez-Duque has extended the more traditional topological tradition in logic by demonstrating the epistemological relevance of the Cantor derivative: work which won him, among other things, the Ray Reiter Best Paper Award for research in AI at the prestigious and highly competitive KR (Knowledge Representation) conference.
There are other strands in Baltag’s research as well, and noteworthy is also his innovative work with Sonja Smets in the philosophy of science offering a fresh perspective on the interface of quantum logic and quantum mechanics in terms of a dynamic logic of quantum measurement in quantum information systems.
It might be added that Baltag is a brilliant and sparkling presence at many academic gatherings, who has an impressive track record in producing excellent students.
We believe that Baltag is a worthy candidate for the Gabbay Prize because of the combination of mathematical strength and philosophical range that shapes his work, features which are also typical of Dov Gabbay’s contributions to Philosophical Logic.
The jury for 2025:
- John T. Baldwin (University of Illinois Chicago, US)
- Johan van Benthem (Amsterdam University, NL/U Stanford, US)
- Christoph Benzmueller (University of Bamberg, DE)
- Laura Giordano (Università del Piemonte Orientale, IT)
- Hannes Leitgeb (LMU Munich, DE)
- Philip Welch chair (University of Bristol, UK)