PL
The main thesis underlying the methodological approach to argument evaluation holds that some arguments which employ knowledge-gaining procedures can be suc-cessfully evaluated by applying tools elaborated by the methodology of science, such as the rules for reasoning, classifying objects, defining, and questioning. The applica-tion of those rules to argument evaluation consists in comparing them with proce-dures employed in the case of argumentative practices performed either in scientific inquiry or in everyday life. In order to show how building the methodological ap-proach to argument evaluation could be started, I examine two cases of evaluating arguments by means of several methodological rules of defining. The idea of apply-ing the rules governing various knowledge-gaining procedures to evaluating argu-ments is present in philosophy of science and in argumentation theory, but so far it has not been systematically elaborated. The paper aims at justifying this idea as a promising research project.