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*Participants:*

- Can Baskent (IHPST, CNRS – Université Paris 1 – ENS)
- Ivano Ciardelli (University of Amsterdam)
- Jeroen Groenendijk (University of Amsterdam)
- Dorota Leszczyńska-Jasion (Adam Mickiewicz University, Poznań)
- Paweł Łupkowski (Adam Mickiewicz University, Poznań)
- Mariusz Urbański (Adam Mickiewicz University, Poznań)
- Andrzej Wiśniewski (Adam Mickiewicz University, Poznań)
- Svetla Yordanova (University of Veliko Turnovo)
- Frank Zenker (Lund University)

*Schedule:*

**18.04**

10.00-13.00 Amsterdam time

** What is this thing called Inquisitive Semantics?** (JG)

There are multiple systems around that have inquisitive semantics or inquisitive logic as part of their name. Like: basic inquisitive semantics, radical inquisitive semantics, unrestricted inquisitive semantics, inquisitive dynamic epistemic logic, deontic inquisitive semantics, inquisitive witness semantics, etc. In this short talk we will try to provide a road map that says how these different systems are related to each other, what the main motivation for each of them is, and how far we are in investigating them.

** On the semantics and logic of declaratives and interrogatives** (JG & IC)

In many natural languages, there are clear syntactic and/or intonational differences between declarative sentences, which are primarily used to provide information, and interrogative sentences, which are primarily used to request information. Most logical frameworks restrict their attention to the former. Those that are concerned with both usually assume a logical language that makes a clear syntactic distinction between declaratives and interrogatives, and usually assign different types of semantic values to these two types of sentences.

A different approach has been taken in recent work on inquisitive semantics. This approach does not take the basic syntactic distinction between declaratives and interrogatives as its starting point, but rather a new notion of meaning that captures both informative and inquisitive content in an integrated way. The standard way to treat the logical connectives in this approach is to associate them with the basic algebraic operations on these new types of meanings. For instance, conjunction and disjunction are treated as meet and join operators, just as in classical logic. This gives rise to a hybrid system, where sentences can be both informative and inquisitive at the same time, and there is no clearcut division between declaratives and interrogatives.

It may seem that these two general approaches in the existing literature are quite incompatible. The main aim of this paper is to show that this is not the case. We develop an inquisitive semantics for a logical language that has a clearcut division between declaratives and interrogatives. We show that this language coincides in expressive power with the hybrid language that is standardly assumed in inquisitive semantics, we establish a sound and complete axiomatization for the associated logic, and we consider a natural enrichment of the system with presuppositional interrogatives.

13.00-14.30 lunch break

14.30-17.30 Poznań time (AW, DL-J, PŁ, MU)

** The Logic of Permittance** (AW)

** Permittance and Erotetic Implication** (MU)

** Three Valued Inferential Erotetic Logic and its Applications** (DL-J & PŁ)

We will present a logic with questions based on the Kleene’s strong three-valued logic. Within this logic we define the concept of an erotetic search scenario. Finally we discuss how such a tool might be used to model the behaviour of a cognitive agent who tries to solve a complex problem by dividing it into sub-problems, but fails to solve some of these sub-problems.

19.00- dinner at Dąbrowskiego 42

**19.04**

10.00-11.30 Paris time

** What is Game Theoretical Negation?** (CB)

Hintikka’s game theoretical semantics enjoys charming simplicity and intuitiveness. However, this intuitiveness is lost when it comes to negation. In this talk, I claim that game theoretical semantics for negation is a meta-game theoretical procedure, and does not carry over to other logics. In order to fix this issue, first, I will offer a classical extension of game theoretical semantics, and then discuss it in non-classical logics. My main focus in this talk will be Priest’s Logic of Paradox, and I will suggest a game theoretical semantics for it, and discuss it with some examples.

11.30-13.30 Amsterdam time

** Inquisitive dynamic epistemic logic** (IC)

Information exchange can be seen as a dynamic process of raising and resolving issues. The goal of this paper is to provide a logical framework to model and reason about this process. We develop an inquisitive dynamic epistemic logic,IDEL, which enriches the standard framework of dynamic epistemic logic, incorpo- rating insights from recent work on inquisitive semantics. At a static level, IDEL does not only allow us to model the information available to a set of agents, like standard epistemic logic, but also the issues that the agents entertain. At a dynamic level, IDEL does not only allow us to model the effects of public announcements that provide new information, like standard DEL, but also the effects of public announcements that raise new issues. Thus, IDEL provides the fundamental tools needed to analyze information exchange as a dynamic process of raising and resolving issues.

13.30-15.00 lunch break

15.00-16.00 Veliko Turnovo time

** Interrogatives help. On some special applications of Erotetic Logic** (SY)

16.00- discussion

*Workshop venue:*

room 70, Institute of Psychology, Adam Mickiewicz University

Szamarzewskiego 89, building AB, Poznań

*Hotels:*

Jowita, Zwierzyniecka 7 (website)

Gaja, Gajowa 12 (website)