Alexandre Thiercelin

Legal theory, political sciences, sociology, philosophy, logic, artificial intelligence: there are many approaches to legal argumentation. Each of them provides specific insights into highly complex phenomena. Different disciplines, but also different traditions in disciplines (e.g. analytical and continental traditions in philosophy) find here a rare occasion to meet. The present book contains contributions, both historical and thematic, from leading researchers in several of the most important approaches to legal rationality. One of the main issues is the relation between logic and law: the way logic is actually used in law, but also the way logic can make law explicit. An outstanding group of philosophers, logicians and jurists try to meet this issue. The book is more than a collection of papers. However different their respective conceptual tools may be, the authors share a common conception: legal argumentation is a specific argumentation context.

I focus on the method designed by the young Leibniz in order to analyze specific legal modalities, the so-called suspensive conditions. Such a method, to analyze the specific conditionals whose if-part is a suspensive condition, gives Leibniz access to the resources of logical analysis of conditionals. I show that the contribution of logic to the law goes hand in hand with an extended complication of the former thanks to which Leibniz achieves at capturing a number of dynamical features of suspensive conditions, but also of resolutory and temporal legal modalities