Séance du 16 février

Jeudi 16 février, 11h-13h

Salle Corbin

Playing with or without a list of announcements?

Sébastien Magnier

Abstract:

In a previous presentation, I have argued that a public announcement does not correspond to any conditional connectives. But in fact there are algorithms of translation that turn any public announcement in a conditional way. These translations do not yield an immediate material implication of annoucement propositions. They give us complex or embedded conditionals whose complexity directly depends of the post-condition of the announcement operator. Now, our aim is to compare the dialogues with those propositions (the one with the public announcement operator on the one hand and its corresponding translation on the other hand). As we shall see, such a study underlines the meaning of the list of announcements. This list represents the story of the commitment of the players. It emphasizes the two distinct levels: play and strategy level which occur in the dialogical framework. The comparison between them also suggests some improvements of the rule (SR-A.1) that will probably entail a weakening of the formal rule.

Séance du 2 février 2012

Jeudi 2 février, 11h-13h

Against the so-called “fictional nature” of Law

Juliele Sievers

Abstract:

In my presentation I will try once more to attack the notion of fiction in Law, this time by using some elements of Amie Thomasson’s artefactual theory and Hans Vaihinger’s Philosophy of As-If. Since the first lecture of those works seems to give the idea that norms have the same characteristics of fictions, I will present some arguments against this interpretation. One of them refers to the multiplicity of interpretations of the term “fiction”, which often leads to confusion in its use. Starting by comprehending that the definition of fiction in Literature, in Science and in Law has totally different aspects will lead us to a strong consequence: that the presence of this term in a prescriptive ambit it’s in fact a misuse of it (and we will also understand why this improper practice is nevertheless so widely spread).

Attention : les horaires du GdT ont changé (voir le message ci-dessous).

Dates et Horaire des séances à venir

Changement de semestre et d'emplois du temps obligent, les séances du Groupe de Travail auront désormais lieu à des horaires différents.

Les séances auront lieu de 11 heures à 13 heures les jeudis suivants :

2 février, 16 février.

8 mars, 22 mars.

5 avril, 12 avril.

10 mai, 24 mai.

7 juin, 28 juin.

Séance du 12 décembre

Lundi 12 décembre, 14h-16h

Salle Corbin

The gap in the proof

Nicolas Clerbout

Abstract:

In my last talk I mentionned a result which holds in propositional and first-order dialogical games, namely that the Proponent has a winning strategy in D(F) if and only if he has one in D1(F), where F is a sentence of the relevant language and D1(F) is the subgame of D(F) where the Opponent chooses rank 1.
I also mentionned that there is currently a gap in the proof of the righ-to-left direction. Briefly, the point is that in order to prove this direction we need to prove that if the Opponent cannot win by chosing rank 1 then she cannot win at all.

The aim of this talk is to discuss and hopefully give the proof of that last claim.

Séance du 5 décembre

Lundi 5 décembre, 14 h - 16h,

Salle Corbin

Formalism towards strategical behaviours

Pierre Cardascia

Résumé :

In my last talk I criticized some hypotheses of our approach calling them "meta", and expressed the desire to wipe them out. I had some arguments, but no formal arguments, so my intervention looked like a moment of poetry in a terrible world. I worked a lot, and today I can implement some important notions I spoke about last time. At the end of this talk the strategical reflexion won't be a black box anymore, but will be defined properly as a function from the rules and a project to the strategical behaviour. Then, maybe I will be able to present the notion of orthogonality of behaviours, then show that all the hypotheses I criticize can be reduced into one result of biorthogonality.
After showing that, you will see that I'm a big cheater, because though I can define the "strategical reflexion", it is very nominative, and then, it will be the next problem I have to solve.

Séance du 28 novembre

Comme annoncé précédemment, la séance prévue le 21 novembre aura lieu ce 28 novembre.

Lieu : Salle D. Corbin

Horaire : 14h-16h

Pour rappel, la séance sera consacrée au thème suivant :

Repetition Ranks and Decidability

Nicolas Clerbout

The aim of the talk is to explain how the question of decidability gets manifested in Dialogical Logic. We will see that a clear and concise formulation of the dialogical manifestation of the decidability (or not) of a logic can be given in terms of repetition ranks.

We will consider the cases of Propositional Logic and First-Order Logic.

Séance du 21/11/11 reportée

La séance prévue ce Lundi 21 novembre est reportée au 28 novembre.

Horaires et salles seront communiqués prochainement.