Logical Dynamics: New trends and interfaces

Logical Dynamics: New Trends and Interfaces
Oct 8th 2011
Peking University


Organized by Beijing Society for Logic, Peking University and Tsinghua University
Workshop Venue:
Conference Room No.2 (ground floor)
Department of Philosophy
Peking University, BEIJING
Date: Oct 8th, 2011

Directions: You may enter PKU from the east gate (there is a metro station) and then walk straight towards the west. You will see a magnificent building ahead of you and that is our main library. Passing it from the left hand side you will see a basketball court. Keep going west and at the west end of the basketball court you should turn right and there is our department (near a big garden called “Jing Yuan”).
Preliminary Program:
9:00 - 12:30 Morning session [New trends of DEL: new examples and ideas]
12:30-14:00 Lunch Shaoyuan
14:30 - 18:00 Afternoon Session [Interfaces: Logical dynamics meets new/old friends]
Workshop Dinner @ Xin Kai Yuan restaurant

Johan van Benthem (Amsterdam&Stanford), Hans van Ditmarsch (Sevilla), Patrick Girard (Auckland), Davide Grossi(Liverpool), Tomohiro Hoshi (Stanford), Fengkui Ju (Beijing Normal Univ.), Kaile Su (Peking), Fenrong Liu (Tsinghua), Ram Ramanujam (IMSc), Olivier Roy (Munich), Yi Wang (Bergen), Tomoyuki Yamada (Hokkaido)
Note: The speakers are expected to give 5-slide presentations
09:00-09:15 Welcome
Session A.1 Chair Tomoyuki Yamada

Hans van Ditmarsch: Five Ways of Quantifying over Information Change
Fenrong Liu: Reasoning about Agent Types
10:15-10:30 Coffee and tea

Session A.2 Chair Hans van Ditmarsch

Patrick Girard: A Product Model Construction for PDL
Yi Wang: Dynamic Epistemic Logic and Distributed Knowledge
11:30 -12:00
Tomohiro Hoshi: Failures of Uniform Substitutions - toward a systematic study of substitution cores
12:00-14:00 Lunch @ Shaoyuan Restaurant
Session B.1 Chair Johan van Benthem

Ram Ramanujam: Desiderata for Reasoning about Large Games
Kaile Su: An Epistemic Logic Approach to Verfication of Security Protocol
15:00-15:30 Davide Grossi: Fixpoints and Iterated Announcements in Abstract Argumentation
15:30-15:45 Coffee and tea
Session B.2 Chair Fenrong Liu

Tomoyuki Yamada: Dynamic Logics of Speech Acts as Formal Simulations of Social Interaction
16:15-16:45 Fengkui Ju: The Notion of Validity for Imperative Inferences
16:45-17:00 Coffee and tea

Session B.3 Chair Ram Ramanujam
17:00-17:30 Olivier Roy: Deontic Logic, Neighborhood Semantics and Games
Johan van Benthem: Local Dynamics in Games, or: DEL + Game Theory = Theory of Play?
Workshop dinner @Xin Kai Yuan Restaurant


Hans van Ditmarsch
Five ways of quantifying over information change

Abstract: In this short presentation I will focus on different epistemic modal logics with quantification over information change. I will present and compare the following alternatives - where 'phi' is any epistemic formula, such as 'Ann knows the deal of cards:
1 <>phi for 'there is an announcement after which phi
2 phi for 'there is an announcement by coalition G after which phi'
3 <[G]>phi for 'there is an announcement by coalition G after which, no matter what the agents not in G do, phi'
4 <>phi for 'there is an action model after which phi
5 <>phi for 'there is a refinement after which phi' (refinement is the dual of simulation, the two direction of bisimulation)

Fenrong Liu
Reasoning about Agent Types

Abstract: TBA

Patrick Girard
A Product Model Construction for PDL

Abstract: We provide a generalisation of BMS in which action models are programs that operate on the relations of models. We can model a wide range of relation changes, a special case being the BMS action of cutting links to states that do not satisfy the preconditions of announcements. Since our models associate actions with real programs, we can explicitly model changes on epistemic, doxastic or preference structures, amongst others, whereas BMS is restricted to encoding actions in pre-conditions. We provide an axiomatisation that reduces the dynamics to PDL. We call the resulting logic "Dynamic PDL". 

Yi Wang
Dynamic Epistemic Logic and Distributed Knowledge

Abstract: We focus on dynamic epistemic logics with distributed knowledge. The starting point is public announcement logic with distributed knowledge, and then we discuss more general frameworks, such as action model logic and PDL. We will discuss the issue regarding "distributed knowledge as knowledge achievable through communication", using APAL and GAL for example. We might also talk about an open question related to distributed knowledge from van Benthem's "Open questions in Logic Dynamics".

Tomohiro Hoshi
Title: Failures of Uniform Substitutions - toward a systematic study of substitution cores

Abstract: In Dynamic Epistemic Logic, there are formulas, such as [p]p, that are valid but not schematically valid. Because of this, DEL is not closed under uniform substitution. This special feature of DEL has been widely studied and some results have been produced in the literature. On the other hand, there are other known logics in which uniform subsitution fails. Can we say anything systematic about the causes of the failure of uniform substitution in different logical systems? If we can, can we use techniques developed in DEL to study substitution cores of other logics?


Ram Ramanujam
Desiderata for Reasoning about Large Games

Abstract: interpersonal subjectivity is the essence of reasoning in games, since players' strategies have to take into account how others would play based on their knowledge and beliefs, and this is of great interest to epistemic logic. however, in games where the number of players is large, players may not even know how many players are in the game, let alone know all their epistemic attitudes. quantitative analysis is still possible based on type distributions and we have some results on this. however, logicising such reasoning runs into several difficulties, and the talk will attempt to highlight these, offering a wish list and a tentative proposal.

Kaile Su
Title: An Epistemic Logic Approach to Verification of Security Protocol


Davide Grossi
Fixpoints and iterated announcements in abstract argumentation

Abstract: In this talk I will present preliminary results on the analysis of some fixpoint-based solution concepts of abstract argumentation via iterated announcements. This will provide an epistemic perspective on those concepts highlighting common issues at the interface of epistemic logic, fixpoint logics and abstract argumentation theory. 

Fengkui Ju
The Notion of Validity for Imperative Inferences

Abstract: There are some imperative inferences which we think are valid intuitively, and there are also some imperative inferences which are invalid intuitively. How should we define the notion of validity for imperative inferences? Imperatives do not have truth values explicitly, so the traditional theory of logical consequence is not directly applicable. I will try to presents a new proposal for this.
Being in force is an important property of imperatives. An imperative is in force if and only if (1) The addressee has to make true the propositional content of this imperative; (2) The addressee may make true the propositional content of this imperative in any way. An imperative inference is valid if and only if in any situation, if its premises are in force, then its conclusion is in force. This notion of validity can explain some of our intuitions about imperative inferences well.

Tomoyuki Yamada
Dynamic Logics of Speech Acts as Formal Simulations of Social Interaction

Abstract: Inspired by the development of various systems of dynamic epistemic logics in the last two decades, dynamic logics of several speech acts are developed recently. The purpose of this paper is to examine what we can learn from the fact that these ``logics'' are available. In order to answer this question, we propose to consider these systems as ``formal simulations''. This enables us to have an interesting dimension of evaluation; we can now ask how good they are as simulations. Moreover, it also allows us to ask whether and how we can improve their performance.

Olivier Roy
Deontic Logic, Neighborhood Semantics an
d Games

Abstract: TBA

Johan van Benthem
Local Dynamics in Games, or:
DEL + Game Theory = Theory of Play?

Abstract: Playing games involves local changes in information, beliefs, and perhaps even preferences. We will see how DEL fares in this real-time setting, on what models, and with what sorts of update actions. What can it contribute to a Theory of Play?