Dear Cheerful Logicians and Friends of Logic, A few reminders/useful things to know:
- The supergroup finally has its own official website. Here's a link <https://sites.google.com/view/logicsupergroup/the-logic-supergroup>. - Universität Regensburg is hosting a virtual workshop on August 27 and 28 that might be of interest to many members. For more information visit this link <https://www.uni-regensburg.de/philosophie-kunst-geschichte-gesellschaft/theoretische-philosophie/workshops/2020/index.html> . - *The Logic Supergroup has a YouTube channel!* Recordings of almost all talks are available at https://www.youtube.com/channel/UCqOAS8SHP-5nGjYEE2FE6xw This week there are two talks to announce. First, on Tuesday at 14:00 GMT-5, Jeremy Avigad is speaking in the Lógicos em Quarentena seminar hosted by the Brazillian Logic Society. The topic is Formal Mathematics and the Lean Theorem Prover. Then, on Friday at 09:00 GMT-5, Eleonora Cresto will give the official supergroup talk of the week. The topic is The Logic of Ungrounded Payoffs. More info below, as usual. Supergroup Talk: Speaker: Eleonora Cresto Title: The Logic of Ungrounded Payoffs Time and Date: Friday August 21, 0900 GMT-5 Link: <https://ksu.zoom.us/j/7613620942> https://ksu.zoom.us/j/98598883520?pwd=N09pdjdyU2NDK2xISU9kcGRCek9VQT09 *Meeting ID:* 985 9888 3520 *Passcode:* Payoffs Abstract: Higher order likes and desires sometimes lead agents to have ungrounded or paradoxical preferences. This situation is particularly problematic in the context of games. If payoffs are interdependent, the overall assessment of particular courses of action becomes ungrounded; in such cases the matrix of the game is radically under-determined. In this talk I propose a dynamic doxastic and preference logic that can mimic the search for a suitable matrix. Upgrades are triggered by conjectures on other players’ utilities, which can in turn be based on behavioral or verbal cues. We can prove that, under certain conditions, pairs of agents with paradoxical preferences eventually come to believe that they are not able to interact in a game. As a result I hope to provide a better understanding of game-theoretic ungroundedness, and, more generally, of the structure of higher order preferences and desires. Talks by Member Groups: *Lógicos em Quarentena* Speaker: Jeremy Avigad Title: Formal Mathematics and the Lean Theorem Prover Time and Date: Thursday, August 20 14:00 GMT-5 Link: https://meet.google.com/ijx-mwhr-fjg Abstract: Since the early twentieth century, it has been understood that mathematical statements can be expressed in formal languages, and mathematical proofs can be represented in formal deductive systems with precise rules and semantics, at least in principle. Remarkably, the development of computational proof assistants over the last few decades has made it possible to do this in practice. The technology is firmly based on the methods and concepts of modern logic, and in many ways the practice represents the contemporary embodiment of the foundational tradition. In this informal talk, I will provide a brief overview of interactive theorem proving and the body of logic that supports it. I will then discuss a particular theorem prover, Lean, its formal library, mathlib, which are attracting a growing community of mathematical users. The Lean community web pages provide a good starting point for more information: https://leanprover-community.github.io/. Other Notes and Announcements: - To access the supergroup calendar, please follow this link: https://calendar.google.com/calendar?cid=ZGhoanNoanF1bGhmaG9xam5scDJlc2o0bDhAZ3JvdXAuY2FsZW5kYXIuZ29vZ2xlLmNvbQ - To access the member groups joint calendar, please follow this link: https://calendar.google.com/calendar?cid=aG8wNWljaGxkNXI2N2oyMnZvY3BzdmRoMWNAZ3JvdXAuY2FsZW5kYXIuZ29vZ2xlLmNvbQ - If you represent a member group and would like your events to appear on the joint calendar, be sure to add them! Contact any of the organizers if you need permission to do so. Yay for logic! -- Você está recebendo esta mensagem porque se inscreveu no grupo "LOGICA-L" dos Grupos do Google. Para cancelar inscrição nesse grupo e parar de receber e-mails dele, envie um e-mail para [email protected]. Para ver esta discussão na web, acesse https://groups.google.com/a/dimap.ufrn.br/d/msgid/logica-l/CAMTR990at2Q9YOuPwxNnz3LuM7jQ9q_mh-LUtUdY%3DaKihqtk6w%40mail.gmail.com.
