The tableaux-constructions have a number of properties which advantageously distinguish them from equivalent axiomatic systems . The proofs in the form of tableaux-constructions have a full accordance with semantic interpretation and subformula property in the sense of Gentzen’s Hauptsatz. Method of tatleaux-construction gives a good substitute of Gentzen’s methods and thus opens a good perspective for the investigations of theoretical as well as applied aspects of logical calculi. It should be noted that application of tableau method in modal, tense, relevant (...) and other non-classical logics is connected with serious difficulties. Tableaux variants are constructed only for a few normal modal systems. As to relevant and paraconsistent logic, the absence of its tableau variants may be considered as a question of special interest. We shall formulate the tableaux for propositional modal system S4.1, S4.2, S4.3, S4.4 and relevant R∗ and E ∗ using Beth’s tableaux construction with indexed formulas. (shrink)

Vladimir Aleksandrovich Smirnov was born on March 2, 1931. He graduated from Moscow State University in 1954. From 1957 till 1961 he was a lecturer in philosophy and logic at the Tomsk University. Since 1961 his scientific activity continued in Moscow at the Institute of Philosophy of Academy of Sciences of the USSR. From 1970 and till the last days of his life V. A. Smirnov was lecturer and then Professor at the Chair of Logic at Moscow State University. V. (...) A. Smirnov played an important role at the Institute of Philosophy of Russian Academy of Sciences being the Head of Department of Epistemology, Logic and Philosophy of Science and Technology, and the Head of Section of Logic. Last years he was the leader of the Centre of Logical Investigations of Russsian Academy of Sciences. In 1990-91 he founded a new non-goverment Institute of Logic, Cognitive Sciences and Development of Personality for performing research, teaching, editorial and organization activity in the field of humanities. At the Department of Philosophy of Moscow State University and at the Institute of Philosophy V. A. Smirnov and his close colleagues have founded a Russian logical school which brought up many talented researchers who work at several scientific centres in various countries. (shrink)