Needed for such dialogue games as dialectic are appropriate standards of fairness and rationality. The rules of procedure of dialectic must describe a game playable by actual human participants. The present paper centers on certain idealizations of the dialectician that are not allowable.

Dialogical logic is a game-theoretical approach to logic. Logic is studied with the help of certain games, which can be thought of as idealized argumentations. Two players, the Proponent, who puts forward the initial thesis and tries to defend it, and the Opponent, who tries to attack the Proponent’s thesis, alternately utter argumentative moves according to certain rules. For a long time the dialogical approach had been worked out only for classical and intuitionistic logic. The seven papers of this dissertation (...) show that this narrowness was uncalled for. The initial paper presents an overview and serves as an introduction to the other papers. Those papers are related by one central theme. As each of them presents dialogical formulations of a different non-classical logic, they show that dialogical logic constitutes a powerful and flexible general framework for the development and study of various logical formalisms and combinations thereof. As such it is especially attractive to logical pluralists that reject the idea of “the single correct logic”. The collection contains treatments of free logic, modal logic, relevance logic, connexive logic, linear logic, and multi-valued logic. (shrink)

In this paper, I try to develop an informal model for the analysis and evaluation of argumentative strategies based on active authorities. The explanations necessary to understand the idea of the model and what is modelled are given through the development of the paper. I first give an example of argumentative activities. After that, the main assumption of the model is given. In the third part, the relevant aspects of the argumentative activity are analysed, while the principles of the evaluation (...) are explained in the fourth part. The informal model is presented in the fifth part. In the final remarks, the suggestions for further work are given, as well as a comparison with some related recent works in argumentation theory. (shrink)

Systems of formal dialectics articulate methods of conflict resolution. To this end they provide norms to regulate verbal exchanges between the Proponent of a thesis and an Opponent. These regulated exchanges constitute what are known as formal discussions.One may ask what moves, if any, in formal discusions correspond to arguing for or against the thesis. It is claimed that certain moves of the Proponent's are properly designated as arguing for the thesis, and that certain moves of the Opponent purport to (...) criticize the tenability or the relevance of the reasons advanced. Thus the usefulness of formal dialectic systems as models for reasonable argument is vindicated.It is then proposed to make these systems more realistic by incorporating in them a norm of Creative Reasoning that removes the severe restrictions to which the Proponent's arguing was hitherto subject. As a consequence, a certain type of irrelevant reason is no longer automatically excluded. Therefore, it is proposed to extend the Opponent's rights to exert relevance criticism. The new dialectic systems are shown to be strategically equivalent to the original ones. Finally, it is stressed that the Opponent's criticism should not be designated as arguing against the thesis. The Opponent criticizes, but does not argue. (shrink)