In a preceding paper [1] it was shown that quantum logic, given by the tableaux-calculus Teff, is complete and consistent with respect to the dialogic foundation of logics. Since in formal dialogs the special property of the 'value-definiteness' of propositions is not postulated, the calculus $T_{eff}$ represents a calculus of effective (intuitionistic) quantum logic. Beginning with the tableaux-calculus the equivalence of $T_{eff}$ to calculi which use more familiar figures such as sequents and implications can be investigated. In this paper we (...) present a sequents-calculus of Gentzen-type and a propositional calculus of Brouwer-type which are shown to be equivalent to $T_{eff}$ . The effective propositional calculus provides an interpretation for a lattice structure, called quasi-implicative lattice. If, in addition, the value-definiteness of quantum mechanical propositions is postulated, a propositional calculus is obtained which provides an interpretation for a quasi-modular orthocomplemented lattice which, as is well-known, has as a model the lattice of subspaces of a Hilbert space. (shrink)

This contribution gives an outline of a game theoretic foundation of the logical structure inherent to the language of a science. Game theoretic approaches to a language were considered and developed by several authors. In this volume Saarinen examines the game theoretic semantics due to Hintikka and the dialog-game semantics due to Lorenzen. In the following I shall not re-examine the approaches by Hintikka and Lorenzen. However, some remarks about Lorenzen’s semantics are necessary since the game theoretic approach considered here (...) is essentially based on the idea of Lorenzen to use dialog-games for a foundation of logic.A systematic game theoretic presentation of the rules of a dialog game was given at first by Lorenz. Starting with certain structural rules which constitute the general scheme of a dialog, a further dialog rule is necessary in order to guarantee a finite game. (shrink)

In this paper I shall attempt to compare the dialogue approach originally advocated by Lorenz and Lorenzen and the game-theoretical approach of Hintikka with each other. I shall not try to present any survey of either one of the approaches and will assume that the reader is familiar with the basic ideas of these theories.The original works of Lorenzen and Lorenz have been reprinted in their while Stegmüller contains a survey (in English) of the basic ideas and results. Works in (...) this tradition which apply the approach to quantum logic include Denecke, Mittelstaedt Mittelstaedt and Stachow, Stachow. The reader will also find van Dunn, Krabbe, Lorenz and Stachow to be relevant.The literature on Hintikka’s game-theoretical semantics as applied both to different formal languages (including infinitary languages and intensional logic) and to natural language is rapidly growing. As for the latter, the reader is referred to papers by Hintikka, Carlson and myself reprinted in Saarinen, to Carlson and ter Meulen, and to Saarinen. (shrink)