Judicial syllogism - integrating non-monotonic logic in a deductive logical form

The judicial syllogism represents one of the most significant and widely accepted applications of logic in the field of law. Alongside the legislative syllogism, it is a part of the broader conceptual framework commonly referred to as the legal syllogism. This logical structure is classified as a type of mediate deductive inference, which proceeds from general to particular statements - a reasoning process traditionally associated with the dictum de omni principle. Although intuitive and traditionally accepted for offering the proper structure for the application of law, the judicial syllogism is inherently static due to its foundation in classical mediate deductive reasoning. It does not accommodate the dynamic nature of judicial processes, where addressing quaestio juris and quaestio facti may modify the premises, thereby altering the conclusions. Therefore, this article intends to analyse the classical types of mediate deductive inferences, the static nature of the judicial syllogism and the shortcomings of this monotonic type of logic where the conclusion does not change once it is derived. After analysing the points in the construction of the judicial syllogism, the article also proposes a way of integrating non-monotonic logic in the elaboration of the judicial syllogism in order to capture the actual dynamic of judiciary processes of applying law to particular cases, without altering the overall structure of the judicial syllogism. The operationalization of this theoretical framework could be of practical relevance in developing computational tools, especially in AI applications.