The article concerns two axiom systems of Słupecki for the functionally complete three-valued propositional logic: W1–W6 and A1–A9. The article proves that both of them are inadequate—W1–W6 is semantically incomplete, on the other hand, A1–A9 governs a functionally incomplete calculus, and thus, it cannot be a semantically complete axiom system for the functionally complete three-valued logic.

A method of constructing Hilbert-type axiom systems for standard many-valued propositional logics was offered by Rosser and Turquette. Although this method is considered to be a solution of the problem of axiomatisability of a wide class of many-valued logics, the article demonstrates that it fails to produce adequate axiom systems. The article concerns finitely many-valued propositional logics of Łukasiewicz. It proves that if standard propositional connectives of the Rosser–Turquette axiom systems are definable in terms of the propositional connectives of Łukasiewicz’s (...) logics, and thus, they are normal ones, then every Rosser–Turquette axiom system for a finite-valued Łukasiewicz’s logic is semantically incomplete. (shrink)

This book presents the heritage of the Lvov-Warsaw School from both the historical and the philosophical perspective. The historical view focuses on the beginnings and the dramatic end of the School brought about by the outbreak of World War II. The philosophical view, on the other hand, encompasses a broad spectrum of issues, including logical, epistemological, axiological, and psychological problems, revealing the interdisciplinary nature of studies carried out by Kazimierz Twardowski and his students. With thirteen diverse and original essays this (...) volume is split into three parts: History, Culture and Axiology; Psychology; and Logic and Methodology. Exploring not only the history of philosophy represented by the Lvov-Warsaw school, the book also reflects on the condition of contemporary philosophy from the perspective of concepts developed by its representatives. Furthermore, the studies presented in this book delve into problems of contemporary science and its distinctive interdisciplinary character. This volume is, therefore, not only a collection of analyses of the Lvov-Warsaw School philosophy, but also an investigation into the interdisciplinarity of science and philosophy itself. (shrink)

The main aim of this article is to prove that Wittgenstein's early philosophy considers two perspectives: the first one from the view of necessary logic and the second one from the view of contingent application of logic in the natural language. The application of logic is the matter of decisions outside the logical necessity - it is arbitrary and thus it can not be anticipated by logic and can not be considered by logical notation (concept-script). According to Wittgenstein 'logic must (...) take care of itself' and only the exclusion of the contingency from the logical notation let maintain the autonomy of logic. (shrink)

The article demonstrates that to describe the property of atomicity of transactions in database systems, we need a three-valued logic with propositional connective characterized in the same way as Blamey’s interjunction. However, the article explains that since Blamey’s partial logic with interjunction is a logic without tautologies, it does not satisfy some salient conditions of being a logic of atomic transactions. The article introduces a logic of the considered kind, and provides an example of the formal exposition of the case (...) of an atomic transaction. Finally, the article explains the philosophical significance of the introduced logic. (shrink)

The article explores the following question: which among the most often examined in the literature method of constructing Hilbert-type axiom systems for finite-valued propositional logics of Łukasi...