From Shared Evidence to Group Attitudes
Final Report Abstract
Complex, coordinated efforts such as organizing national intelligence, rescuing flood victims, or conducting large-scale scientific research require both pooling and sharing information. These two processes are related but different. A commanding officer may pool intelligence and be able to locate a target while an agent in the field is unable to do so. The fact that the intelligence is not shared, or “out in the open” for all field officers, might even be crucial to the success of the operation. What is, then, the precise relationship between pooling and sharing information? Is shared information always pooled? How can individuals with limited time and resources effectively share and/or pool the information they have? The SEGA project aimed at studying these questions while at the same time lifting two important idealizations that most previous models of pooled and shared knowledge have made. On the one hand, the agents in these models are “logically omniscient”, i.e., they know all the logical consequences of their information. On the other hand, standard logical models also assume that the agents can store highly complicated notions, for instance an unbounded number of iterations of “everybody knows that everybody knows that…”, which are at the heart of the definition of so-called “common knowledge.” The work on the SEGA project took three decisive steps towards lifting these idealizations. First, the project members developed novel logical models of shared information, e.g. common knowledge, for agents who do not have the full deductive power of the classical models. Second, they studied both generalizations and alternative models of information pooling, drawing from substructural logic and the theory of so-called priority merge operations. Finally, they studied the logical models of questions, and applied them to epistemic logic in order to understand the conditions under which shared and common knowledge can be reached. The project featured six project-wide meetings, bringing together project members and leading scholars as invited speakers. The project also financed three visits of Czech team members to Germany, each of which resulted in concrete joint publications.
Publications
-
“Erotetic Epistemic Logic”, Logic and Logical Philosophy, vol. 26, no. 3, 2017, pages 357-381
Peliš, M.
-
“Substructural logics for pooling information”. In: Baltag, A., Seligman, J. and Yamada, T. (eds.) Logic, Rationality, and Interaction, 6th International Workshop, LORI 2017, Springer, 407-421, 2017
Punčochář, V., Sedlár, I.
-
(2018) “Knowledge, belief, normality, and introspection”, Synthese (2018) 195:4343–4372
Klein, D., Roy, O., Gratzl, N.
-
(2018) “Lindenbaum and Pair Extension Lemma in Infinitary Logics”. In: Moss L., de Queiroz R., Martinez M. (eds) Logic, Language, Information, and Computation. WoLLIC 2018. Lecture Notes in Computer Science, vol 10944. Springer, Berlin, Heidelberg
Bílková M., Cintula, P., Lávička, T.
-
“Epistemic Erotetic Search Scenarios. Logic and Logical Philosophy”, Vol. 27, No. 3 (2018), s. 301-328
Lupkowski, P., Majer, O., Peliš, M., Urbanski, M.
-
“Substructural Inquisitive Logics”, The Review of Symbolic Logic, volume 12, issue 2, June 2019, pp. 296-330
Punčochář, V.
-
(2020). “Pooling Modalities and Pointwise Intersection: Axiomatization and Decidability”, Studia Logica
Van De Putte F., Klein, K.
-
"Priority Merge and Intersection Modalities." The Review of Symbolic Logic (2021): 1-32
Christoff, Z., Gratzl, N., Roy, O.
-
“Probabilities with Gaps and Gluts”, J Philos Logic (2021)
Klein, D., Majer, O., Rafiee Rad, S.
-
“Revisiting Epistemic Logic with Names”. In: Joseph Halpern and Andrés Perea: Proceedings Eighteenth Conference on Theoretical Aspects of Rationality and Knowledge (TARK 2021), Beijing, China, June 25-27, 2021, Electronic Proceedings in Theoretical Computer Science 335, pp. 39– 54
Bílková, M., Christoff, Z., Roy, O.
