Ana Dimiskovska (Skopje): Logic, argumentation and law: What can a logician learn from the study of legal reasoning?

Abstract:

The question of the logical status of legal reasoning has inspired many theoretical controversies in contemporary research in the field of logic and argumentation. On one hand, as the influential work of Perelman has shown, legal reasoning and argumentation represent a “hard nut” for the explanatory capacities of the paradigm of deductive, formal logic. According to Perelman, while in (analytic) syllogistic reasoning the transition from the premises to the conclusion is always logically necessary, it is not the same for the transition from arguments to a decision in legal reasoning, for “a decision always presupposes the possibility to decide in a different way, or not to decide at all”. Consequently, legal logic should be treated as specific kind of logic, essentially non-formal in nature.

On the other hand, as opponents of this anti-formalist view have tried to show, the acceptance of this thesis of the specific, non-formal character of legal logic would have unpleasant consequences for its normative authority and rational force because it would seriously limit its pretensions to universality and content-independent applicability. Some of Perelman’s critics, for example, Joseph Horovitz, find that Perelman’s view rests on an unwarranted identification of the concepts “deductive” and “formal”, i.e. of the set of conclusive, deductive arguments with the set of formal or formalizable arguments. Horovitz argues for a possible formal yet non-deductive logic as a theory of the rational force of non-conclusive arguments, in the framework of which typical legal argument could be adequately represented and formalised.

More recent philosophical and logical investigations of legal reasoning generally accept the view of its logical specificity, which is untreatable by the resources of classical, deductive logic. This specificity arises from several different sources: the “open texture” of natural-language concepts in which legal rules are formulated, the need for their interpretation, the existence of exceptions, possible conflicts, etc. However, in contemporary investigations, Perelmanian scepticism towards the possibility of formal treatment of the logical features of legal reasoning is not often shared. On the contrary, the need for building new and more sophisticated formal logical tools for the representation and analysis of legal reasoning is widely recognised, and practically realised in several theoretical platforms, especially in theories of defeasible reasoning and non-monotonic logic.

My lecture focuses on the wider philosophical presuppositions and implications of the plea for constructing new logical tools for the analysis, representation and evaluation of legal arguments. I try to show that the main benefit of the study of legal reasoning is the insight that there is a need for fundamental interventions in the conceptual and formal basis of classical logic in order to increase its relevance and applicability to important areas of practical and theoretical rationality. I emphasize three conceptual modifications to standard logical theory derived from logical investigations of legal reasoning: 1) the need to rethink and develop further the concept of logical consequence; 2) the need to build a different classification of types of reasoning richer than the standard dichotomies (analytical/dialectical, inductive/deductive reasoning etc.) and 3) the need to replace the monological form of the modelling of reasoning, characteristic of the formal deductive  paradigm, with models of dialogical-procedural character.