In this paper, the four Judaic inference rules: qal wa- ḥ omer, gezerah š awah, heqe š, binyan 'av are considered from the logical point of view and the pragmatic limits of applying these rules are symbolic-logically explicated. According to the Talmudic sages, on the one hand, after applying some inference rules we cannot apply other inference rules. These rules are weak. On the other hand, there are rules after which we can apply any other. These rules are strong. This means that Judaic inference rules have different pragmatic meanings and this fact differs Judaic logic from other ones. The Judaic argumentation theory built up on Judaic logic also contains pragmatic limits for proofs as competitive communication when different Rabbis claim different opinions in respect to the same subject. In order to define these limits we build up a special kind of syllogistics, the so-called Judaic pragmatic-syllogistics, where it is defined whose opinion should be choosen in a dispute.

Formal dialogue systems model rule-based interaction between agents and as such have multiple applications in multi-agent systems and AI more generally. Their conceptual roots are in formal theories of natural argumentation, of which Hamblin’s formal systems of argumentation in Hamblin (Fallacies. Methuen, London, 1970, Theoria 37:130–135, 1971) are some of the earliest examples. Hamblin cites the medieval theory of obligationes as inspiration for his development of formal argumentation. In an obligatio, two agents, the Opponent and the Respondent, engage in an alternating-move dialogue, where the Respondent’s actions are governed by certain rules, and the goal of the dialogue is establishing the consistency of a proposition. We implement obligationes in the formal dialogue system framework of Prakken (Knowl Eng Rev 21(2):163–188, 2006) using Dynamic Epistemic Logic (van Ditmarsch et al. in Dynamic epistemic logic, Synthese Library Series. Springer, Berlin, 2007). The result is a new type of inter-agent dialogue, for consistency-checking, and analyzing obligationes in this way also sheds light on interpretational and historical questions concerning their use and purpose in medieval academia.

Keeping in touch with pragma-dialectics contains 17 contributions written for Frans van Eemeren on the occasion of his retirement. Publications 'in honor of' are always entertaining for all who are sympathetic to the laureate (let us consider a retirement as a tribute to a long and very fruitful career) but may lack a clear focus that is shared by the majority of the contributors, may lack the weight to be considered as a substantial contribution to the discipline. The somewhat 'empty' title of this volume may support that expectation. That would be a pity! Keeping in touch with pragmadialectics could have carried the much too lengthy subtitle: Exploring the expressiveness and the limits of the extended pragma-dialectic argument theory; a meta-dialectical exercise.

Giving Reasons has the ambition of developing a new theoretical approach to argumentation that integrates logical, dialectical and rhetorical aspects. The author uses speech act theory to realize her ideal of 'a linguistic-pragmatic approach' to argumentation. After a severe criticism of the major existing approaches to the study of argumentation, the author develops what she claims to be ''a systematic and comprehensive theory of the interpretation, analysis and evaluation of arguments.''

The introduction of the concept of strategic maneuvering into the pragma-dialectical theory makes it possible to formulate testable hypotheses regarding the persuasiveness of argumentative moves that are made in argumentative discourse. After summarizing the standard pragma-dialectical approach to argumentation, van Eemeren, Garssen, and Meuffels explain what the extension of the pragma-dialectical approach with strategic maneuvering involves and discuss the fallacies in terms of the extended pragma-dialectical approach as derailments of strategic maneuvering. Then they give an empirical interpretation of the extended pragma-dialectical model in which they report the testing of three hypotheses which formulate preliminary conditions for effectiveness research within the framework of the extended pragma-dialectical theory and the results of the tests they consecutively carried out.