A methodology of argumentation and a perspective of incredulity are essential ingredients of all intellectual endeavor, including that associated with the art and science of medical care.Traditio argumentum respectus (tradition of respectful argumentation) as a principled system of assessing the validity of beliefs, opinions, perceptions, data, and knowledge, is worthy of practice and perpetuation, because assessments of validity are susceptible to incompleteness, incorrectness, and misinterpretation. Since the latter may lead to ambiguity, uncertainty, anxiety, and animosity among the individuals (patients and (...) physicians) involved in such dialogue, objective analyses and criteria are desirable. A tradition of respectful argumentation is a means to this end—to maximize objectivity and minimize subjectivity as part of decision-making processes and to preserve the integrity of the participants in a patient-physician relationship. During such discourse one must always be cognizant of fallacious arguments—material, verbal, and formal fallacies—since they compromise the validity of assertions. This essay summarizes a classification of fallacious arguments, by definition and by example, predicated upon the intellectual tradition of Occidental Society; and advocates a tradition of respectful argumentation to nullify them. (shrink)