Jelle Gerbrandy

I am doing research at the Dipartimento di Informatica in Turin. Research interests include modal logic, and in particular dynamic and epistemic logic, and game theory. Here's my scientific curriculum and a list of publications.

From 1994 to 1999 I was a Ph.D. student and later, a researcher, at the Institute of Logic, Language and Computation at the University of Amsterdam. The main theme of my Ph.D. thesis Bisimulations on Planet Kripke is that of dynamic epistemic semantics: roughly, the study of information change in a multi-agent framework. It touches upon some related subjects as well, such as distributed knowledge, bisimulation, non-well-founded set theory, and some epistemic puzzles.

My thesis won the Beth dissertation award for outstanding dissertations in the fields of Logic, Language and Information from the Association of Logic, Language and Information, while according to the Philosopher's Annual I wrote (together with Willem Groeneveld) one of the ten best articles to appear in the field of philosophy in 1997.

From 2000 onwards, I have been working as a one-man software company conveniently called Gerbrandy Software specializing in "data" - mostly creating or advising on databases and database-driven internet applications.

In 2004 I have returned to doing research again, first as a Langrange Fellow, later as a researcher.


My research interests can be roughly divided in the following themes. If you are looking for a spefic paper, then go to the publication list.

Dynamic Epistemic Logic

I had the pleasure to co-invent the field of Dynamic Epistemic Logic in my Ph.D. thesis Bisimulations on Planet Kripke and the related papers Dynamic Epistemic Logic and Reasoning about information change. DEL has now become a mature field, with an extended literature, research done all over the world, and even an overpriced text book published by Springer.

More recent contributions include a paper on the relationship between dynamic epistemic logic and epistemic temporal logic of interpreted systems. This is joint work with Johan van Benthem and Eric Pacuit. An extended version is available as an ILLC preprint.

Another topic is the logic of probabilistic information change. In the paper Dynamic update with probabilities, which was written with Johan van Benthem and Barteld Kooi, we develop a formal model of "dynamic epistemic probabilistic logic" and prove completeness results.

An article on the surprise exam paradox is a more philosophically oriented application of DEL to a classical problem.

Game theory and Communication

A paper on communication strategies in games was published in the Journal of Applied Non-Classical Logics. It explores the idea that the effect of communication can be modeled as a change the informational structure of a game, and how that may lead to a pragmatic theory of dialogue based on game theory.

Together with Guido Boella and Joris Hulstijn we worked on the idea that it might be possible to formally prove (using tools from game theory and mechanism design) that if you know something about what participants in a dialogue game want, one needs to be less explicit about the rules that guide them. We presented a A flexible method for dialogue design at the TARK conference that develops this idea in a precise way.

Action logics and Game Logics

"Game Logics" such as ATL (Alternating time temporal logics) are a fascinating topic. With with Wiebe van der Hoek, Luigi Sauro and Michael Wooldridge we explore some of the issues related to planning and action languages in a paper called Reasoning about Action and Cooperation. Luigi and me continued with this work in a paper titled Plans in Cooperation Logic.

A related topic is that of Logics of Propositional Control -- modal logics to reason about a specific type of game in which players control certain decision variables.

Natural Language Semantics

The papers identity in epistemic semantics and Questions of Identity explore the issue of de re and de dicto identity in epistemic contexts, and develop a formal framework for understanding certain problems here.

In Quantifiers in Dependency Tree Semantics, with Livio Robaldo and Leonardo Lesmo, we reconsider the question of quantifier scope of generalized quantifiers in the light of a new syntactic theory. This is mostly Livio's work, but I helped enough with the semantics of the scope of generalized quantifiers to be mentioned as a co-author.

In Changing the common ground I tried to prove that it is impossible to capture all subtleties of individual information change using a single model of the common ground.


A paper on about the role of bisimulation and epistemic equivalence.


Here's a publication list with the more finished articles.


Dipartimento di Informatica, Corso Svizzera 185, 10149, Torino, Italy

last updated on june 30, 2007