Bulletin of the Section of Logic 2021-08-18T11:12:36+00:00 Andrzej Indrzejczak Open Journal Systems <div style="text-align: justify;"> <p>The&nbsp;<em>Bulletin of the Section of Logic</em>&nbsp;(<em>BSL</em>) is a quarterly peer-reviewed journal published with the support of the Lodz University Press. The&nbsp;<em>BSL</em>&nbsp;was founded in 1972 by Ryszard Wójcicki, Head of the Section of Logic of the Polish Academy of Sciences, then based in Wrocław, as a newsletter-journal designed for the exchange of scientific results among members of the Section with their national and international partners and colleagues. From1975 to 2018 the journal was managed and edited by Grzegorz Malinowski. In 1992 the Department of Logic at the University of Łódź took over the publication from the Polish Academy of Sciences changing its policy into regular peer-reviewed journal. The aim of the&nbsp;<em>Bulletin</em>&nbsp;is to act as a forum for the prompt wide dissemination of original, significant results in logic through rapid publication. The&nbsp;<em>BSL</em>&nbsp;welcomes especially contributions dealing directly with logical calculi, their methodology, application and algebraic interpretations.</p> </div> Towards a Logic of Value and Disagreement via Imprecise Measures 2020-11-19T14:44:51+00:00 Federico L. G. Faroldi <p>After putting forward a formal account of value disagreement via imprecise measures, I develop a logic of value attribution and of (dis)agreement based on (exact) truthmaker semantics.</p> 2021-06-30T00:00:00+00:00 Copyright (c) 2021 The Good, the Bad and the Right: Formal Reductions among Deontic Concepts 2020-11-13T20:08:36+00:00 Daniela Glavaničová Matteo Pascucci <p>The present article provides a taxonomic analysis of bimodal logics of normative ideality and normative awfulness, two notions whose meaning is here explained in terms of the moral values pursued by a given community. Furthermore, the article addresses the traditional problem of a reduction among deontic concepts: we explore the possibility of defining other relevant normative notions, such as obligation, explicit permission and Hohfeldian relations, in terms of ideality and awfulness. Some proposals in this respect, which have been formulated in the literature over the years, are here improved and discussed with reference to the various logics that we will introduce.</p> 2021-06-30T00:00:00+00:00 Copyright (c) 2021 Tableau Systems for Epistemic Positional Logics 2020-08-14T07:34:58+00:00 Mateusz Klonowski Krzysztof Aleksander Krawczyk Bożena Pięta <p>The goal of the article is twofold. The first one is to provide logics based on positional semantics which will be suitable for the analysis of epistemic modalities such as ‘agent ... knows/beliefs that ...’. The second one is to define tableau systems<br />for such logics. Firstly, we present the minimal positional logic MR. Then, we change the notion of formulas and semantics in order to consider iterations of the operator of realization and “free” classical formulas. After that, we move on to weaker logics in order to avoid the well known problem of logical omniscience. At the same time, we keep the positional counterparts of modal axioms (T), (4) and (5). For all of the considered logics we present sound and complete tableau systems.</p> 2021-06-30T00:00:00+00:00 Copyright (c) 2021 Extended MR with Nesting of Predicate Expressions as a Basic Logic for Social Phenomena 2021-03-18T10:40:28+00:00 Aleksander Parol Krzysztof Pietrowicz Joanna Szalacha-Jarmużek <p>In this article, we present the positional logic that is suitable for the formalization of reasoning about social phenomena. It is the effect of extending the Minimal Realisation (<strong>MR</strong>) logic with new expressions. These expressions allow, inter alia, to consider different points of view of social entities (humanistic coefficient). In the article, we perform a metalogical analysis of this logic. Finally, we present some simple examples of its application.</p> 2021-06-30T00:00:00+00:00 Copyright (c) 2021 Common Knowledge, Common Attitudes and Social Reasoning 2020-06-05T02:23:14+00:00 Richmond H. Thomason <p>For as long as there have been theories about common knowledge, they have been exposed to a certain amount of skepticism. Recent more sophisticated arguments question whether agents can acquire common attitudes and whether they are needed in social reasoning. I argue that this skepticism arises from assumptions about practical reasoning that, considered in themselves, are at worst implausible and at best controversial. A proper approach to the acquisition of attitudes and their deployment in decision making leaves room for common attitudes. Postulating them is no worse off than similar idealizations that are usefully made in logic and economics.</p> <p><input id="idg-io-safe-browsing-enabled" type="hidden" /></p> 2021-06-30T00:00:00+00:00 Copyright (c) 2021 Reasoning about Social Phenomena 2021-08-18T11:12:36+00:00 Tomasz Jarmużek Fengkui Ju Piotr Kulicki Beishui Liao 2021-06-30T00:00:00+00:00 Copyright (c) 2021