FROM GAMES TO DIALOGUES AND BACK Towards a general frame for validity

In this article two game-theoretically flavored approaches to logic are systematically compared: dialogical logic founded by Paul Lorenzen and Kuno Lorenz, and the game-theoretical semantics of Jaakko Hintikka. For classical Propositional logic and for classical First-order logic, an exact connection between ‘intuitionistic dialogues with hypotheses’ and semantical games is established. Various questions of a philosophical nature are also shown to arise as a result of the comparison, among them the relation between the model-theoretical and proof-theoretical approaches to the philosophy of logic and mathematics.