The purpose of this paper is to examine how and why philosophy and jurisprudence come to grapple with the common problems in their recent developments of the study in practical (legal) argumentation and the normative discussions on justice. The paper consists of three parts. After reviewing briefly how philosophy and jurisprudence come to re-evaluate the notion of practical reason (phronesis, prudentia) in part I, the author attempts to elucidate how the criteria of dialogical rationality are institutionslizd in the legal system and judicial procedure and to inquire into the internal relations between dialogical rationality and procedural justice in parts II and III. Contents of parts II and III are as follows. II : The dialogical rationail...