DIEP talk: Alexandru Baltag

I present some applications of logical methods (in particular, of so-called dynamic epistemic logics) to the study of emergent phenomena in groups of `agents’, capable of reflection, communication, reasoning, argumentation etc.The main focus on the understanding of belief/preference formation and diffusion in social networks, and on how this affects the group’s “epistemic potential”: the ability of the agents to track the truth of the matter (with respect to some given relevant topic). While in some cases, “wisdom of the crowds” can increase the epistemic potential, in other situations  the group’s dynamics leads to informational distortions (– the “madness of the crowds”: cascades, “groupthink”, the curse of the committee, pluralistic ignorance, group polarization, doxastic cycles etc). I explain how logic (in combination with probabilistic methods) can be used to provide some explanations for both types of situations, as well as to suggest some partial solutions to informational distortions.