Several legal arguments use the notion of ratio legis in order to sustain a normative conclusion, in particular the argument from analogy and some forms of teleological argumentation. However, determining the ratio is often a difficult and controversial task. In this paper we look firstly at the speech acts typically performed by legal practitioners in order to determine the ratio and, secondly, we take into account the argumentative commitments they undertake in so doing and the argumentative constraints put on them. (...) This will lead us to distinguish different uses of the notion of ratio legis and to ask on what conditions each of them is justified. (shrink)

We provide a retrospective of 25 years of the International Conference on AI and Law, which was first held in 1987. Fifty papers have been selected from the thirteen conferences and each of them is described in a short subsection individually written by one of the 24 authors. These subsections attempt to place the paper discussed in the context of the development of AI and Law, while often offering some personal reactions and reflections. As a whole, the subsections build into (...) a history of the last quarter century of the field, and provide some insights into where it has come from, where it is now, and where it might go. (shrink)

In practical reasoning, reasonableness ‐ as opposed to rationality ‐ is an important concept. This paper explores the notion of reasonableness as applied exclusively to legal decisions. Conflicting values or legal requirements can make rationally deduced solutions unattainable, and may call for criteria of reasonableness, Conflicting values must be weighed, and weighed against each other, in search of a point of equilibrium between them. Legal cases are more or less difficult to solve, depending on the difficulty of finding a unique (...) optimal equilibrium. The relevance of factual and ideal consensus for the determination of a reasonable legal decision is underlined. Finally, a definition of “reasonable legal decision” is proposed. (shrink)

In this article, we try to trace the relationship between semiotics and theory of legal reasoning using Peirce’s idea that all reasoning must be necessarily in signs: every act of reasoning/argumentation is a sign process, leading to “the growth of knowledge. The broad scope and universal character of Peirce’s sign theory of reasoning allows us to look for new conciliatory paradigms, which must be presented in terms of possible synthesis between the traditional approaches to argumentation. These traditional approaches are strongly (...) affected by either the dialectical (logical) perspective or the rhetorical perspective on argumentation, while Peirce’s approach tends to reconcile the rhetorical and methodological aspects of reasoning. This reconcilation is best illustrated by Peircean analysis of argument’s logical and rhetorical structure; while the diagrammatic (iconic) analysis of arguments is performed in the system of Existential Graphs (which is Peirce’s major methodological system, designed for the expressions of propositions in point of their relational structure). Obviously, Peirce’s original division of argument parts offered only the characterisation of the sign activity (involved in the process of reasoning), and thus left much to be desired in terms of practical explication. (shrink)

In this contribution two approaches of legal analogy-argumentation will be discussed: the traditional, monological approach and the dialogical approach. This contribution aims at answering the question in how far these approaches may serve as adequate instruments for rational reconstructions of this analogy-argumentation. We will also indicate along which lines the insights resulting from these approaches may be developed further in order to arrive at a more comprehensive and systematic method for a rational reconstruction of argumentation of this sort. We will (...) make use of the insights gained from the pragma-dialectical argumentation theory. (shrink)

In this paper I investigate the similarities betweenthe dialectical procedure in the pragma-dialecticaltheory and dialectical procedures in AI and Law. I dothis by focusing on one specific type of reasoning inlaw: analogy argumentation. I will argue that analogyargumentation is not only a heuristic forfinding new premises, but also a part of thejustification of legal decisions. The relevantcriteria for the evaluation of analogy argumentationare not to be found at the logical level of inference,but at the procedural level of the discussion. I (...) willproceed as follows. I start with an outline ofPrakken's theory of argumentation frameworks andprocedural models. Then, I will discuss Peczenik'sanalysis of analogy argumentation and try to combineit with the descriptive-normative research ofMacCormick and Summers. Finally, I propose asystematization of the criteria for the evaluation ofanalogy argumentation within the framework of apragma-dialectical notion of an argumentation scheme. (shrink)

Dans cet article, je souligne le lien profond qui relie la philosophie pratique de Ricœur à la question du langage. J’insiste sur le fait que celle-ci donne son unité à celle-là, parce qu’elle en constitue l’axe privilégié, pour des raisons méthodologiques. Je rappelle la définition que Ricœur donne du discours et explique ses différentes dimensions transphrastiques. Je montre ensuite que cette philosophie du langage est soigneusement réinvestie dans une logique du jugement très cohérente, qui sous-tend ses développements épistémologiques touchant les (...) disciplines normatives. J’insiste tout particulièrement sur la logique du jugement judiciaire. (shrink)