Dear Cheerful Logicians and Friends of Logic, Supergroup announcement time! This week Johannes Stern speaks in the Foundational Studies Bristol series, Marcelo Finger speaks in the Lógicos em Quarentena Series hosted by the Brazilian Logic Society, and Roy Cook will speak in the Supergroup series. Details below.
Also important: the 24 hours of inclusive logic happened and was *awesome*. Stay tuned as we process, update, edit, improve and continue the work begun there! Supergroup Talk: *Speaker*: Roy T. Cook *Title*: On the Expressive Completeness of Minecraft *Time and Date*: Thursday June 18, 8pm GMT-5 *Link*: https://ksu.zoom.us/j/92850665099 *Password*: 038519 *Abstract*: Redstone is a system of components in the Minecraft video game that allows players to build various virtual machines. If we merely consider whether a redstone circuit is powered or not, then redstone circuitry is both functionally complete with respect to classical propositional functions (since it is easy to build, e.g., a NOR gate) and Turing complete (in the slightly attenuated practical sense, often mobilized in computer science discussions, that ignores the finitude of the memory in any particular machine). Much has been made of this as a means to teach basic propositional logic, and ambitious minecraft players have built fully functional (finite memory) universal Turing machines within the game. The Minecraft redstone circuitry system is, however, far more complex than this. Circuits are not merely on or off, powered or unpowered. Instead, the voltage running through a redstone circuit varies from level 0 (unpowered) to level 15 (fully powered). Hence, redstone circuitry involves a sixteen-valued logic. In this talk I will prove that the available redstone components in Minecraft are functionally complete with respect to sixteen-valued truth functions, and in fact are redundant - not all available components are required for the proof. Along the way we will also see some interesting examples of the kinds of computing machines that can be built within Minecraft, including a sixteen-valued memory circuit. Talks by Member Groups *Foundational Studies Bristol* *Speaker*: Johannes Stern (Bristol) *Title*: Belief, Truth, and Ways of Believing *Time and Date*: Tuesday, June 16, 9am GMT-5 *Link*: https://zoom.us/j/97580574018 *Abstract*: The notions of belief and truth frequently interact in philosophical discourse but, surprisingly, a coherent semantics for such discourse is still wanting. Indeed, a number of puzzles stand in way of a satisfactory semantic account of the notion of truth in doxastic and epistemic contexts. In this talk I will discuss these puzzles and then sketch a semantic account that combines ideas from contextualist theories of attitude reports and Awareness semantics for non-idealized belief. *Lógicos em Quarentena* (Brazilian Logic Society) *Speaker*: Marcelo Finger *Title*: Logic and Numbers *Time* and Date: Wednesday, June 17, 6pm GMT-5 *Link*: meet.google.com/het-yrdu-qsd *Abstract*: We present a research program which investigates the intersection of deductive reasoning with explicit quantitative capabilities. These capabilities encompass probabilistic reasoning, counting and counting quantifiers, and similar systems. The need to have a combined reasoning system that enables a unified way of reasoning with quantities has always been recognized in modern logic, as proposals of probabilistic logic reasoning are present since the work of Boole [1854]. Equally ubiquitous is the need to deal with cardinality restrictions on finite sets. More recently, a well-founded probabilistic theory has been developed for non-classical settings as well, such as probabilistic reasoning over Lukasiewicz infinitely-valued logic. We show that there is a common way to deal with these several deductive quantitative capabilities, involving a framework based on Linear Algebra and Linear Programming. The distinction between classical and non-classical reasoning on the one hand, and probabilistic and cardinality reasoning on the other hand, comes from the different family of algebras employed. The quantitative logic systems also allow for the introduction of inconsistency measurements, which quantify the degree of inconsistency of a given quantitative logic theory, following some basic principles of inconsistency measurements. On the computational level, we aim at exploring quantitative logic systems in which the complexity of reasoning is "only NP-complete". We provide open-source implementations for solvers operating over those systems and study some notable empirical properties, such as the presence of a phase transition. Other Notes and Announcements: - Walter Dean (Warwick) is giving a talk at the Aristotelian Society that some supergroup members might be interested in. More details are available here: https://www.aristoteliansociety.org.uk/the-proceedings/the-2019-20-programme/walter-dean/?mc_cid=167a20ee4f&mc_eid=380a4e9011 - The Web School on Logic, Language, and Information is happening July 11-19. More information at https://www.brandeis.edu/nasslli2020/. Of particular interest to our members might be the workshop called Natural Logic Meets Machine Learning; more info at https://typo.uni-konstanz.de/naloma20/. - 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 me if you need permission to do so. Yay for logic! Shay -- 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/CAMTR990naGGW%3D6zHRcr67hZ%3DTDnfwBcxT773FwJqAwZjc0O0kA%40mail.gmail.com.
