We live in an information network and in an exchange of opinions that is ubiquitous and constant – a net of epistemic acts that we exchange with other agents and affect what we end up believing and deciding. Working with information implies more and more that we face the social effects of this – and these are today faster and faster, and we get a glimpse of them in real time. However, the more agents we have involved, the harder to understand the dynamics of information release turn to be.

This course introduces a formal toolkit that helps in this enterprise.
In particular, the course aims at securing: (1) the understanding of the problems of reasoning that can be triggered by the release of information; (2) the understanding of models that capture the dynamic effects of information release, and the conceptual problems they raise; (3) the problems connected to the representation of belief-merging and, in general, the relations between individual and collective notions of epistemic attitudes;
(4) the understanding of the conditions at which consensus is possible, the role it can play, and the relation between the information release policies, the connection of the epistemic network, and the hierarchies and trust distribution in epistemic communities.

(3) e (4) presuppose (1) and (2). In turn, the last two objectives come with a view on the social impact that the information release policies have on a community of epistemic agents. The course employs a varied package of methods and tools, especially those from Epistemic Logic and Dynamic Epistemic Logic, but also, to a lesser extent, notions and methods from Judgement Aggregation and Network Epistemology, which the course will briefly introduce.

teacher profile | teaching materials

Mutuazione: 20710706 LOGICS OF INFORMATION AND ACTION - LM in Informazione, editoria, giornalismo LM-19 CIUNI ROBERTO


The course discusses the epistemic dynamics that result in new beliefs and new knowledge when new information is released. In particular, we discuss the effect of information release – be such information truthful or not – on the community of epistemic agents that receive the information and can mutually engage in communication exchanges. To this purpose, the course will introduce the formal representation of (individual and collective) notions of knowledge and belief, the formal representation of information release dynamics (public observation, private or semi-public observation, testimony by other agents), and it will discuss how the connection within a given group of agents (or among different groups of agents) can be relevant in the way opinions are spread within given societies of epistemic agents.
In order to do so, the course will introduce one formal framework for representing (and reasoning about) the phenomena above: Dynamic Epistemic Logic, which extends the static framework of Epistemic Logic. In addition, the course will discuss some basic aspects of Judgement Aggregation Theory, Belief Merging and Network Epistemology.
The approach is ‘bottom-up’: we start from puzzles, problems of reasoning, and specific phenomena we need to understand, we go to tools designed to solve or approach them, and then we move further to the theories in which such tools are defined and discussed. The course will be taught in English.

Core Documentation

Main texts:

van Ditmarsch H. and Kooi B., One Hundred Prisoners and a Lightbulb, Springer, Berlin, 2015.

van Benthem J., Logical Dynamics of Information and Interaction, Cambridge University Press, Cambridge. Chapters 1 – 4, 7, and 12 – 13.

Type of delivery of the course

Lectures. Participation of students will be required in different occasions during classes. When feasible, the lectures will start by discussing specific puzzles and problems involving or concerning the effect of information release on the beliefs and knowledge of groups of two or more agents. Participation is required especially in these occasions. The class will be taught in English. In case the medical emergency connected with COVID-19 is extended or reinstated, the possible dispositions governing teaching activities will be adopted.

Type of evaluation

There will a written exam after the course ends. Valuation will consider and depend on: 1) Knowledge of the conceptual contents presented through the lectures; 2) The mastery of epistemic reasoning through concrete problems of reasoning (epistemic puzzles); 3) The ability of answering in a clear and precise way. In case the medical emergency connected with COVID-19 is extended or reinstated, the possible dispositions governing teaching activities will be adopted.