Abstract

SummaryThis paper is a critical examination of argumentum ad ignorantiam, or arguing from ignorance. Ad ignorantiam is regarded as a fallacy, and certainly no route to knowledge, by most philosophers. However, case studies of ad ignorantiam are almost non‐existent, and theoretical discussions few in number. Thus this paper begins with a number of case studies. From them some morals are drawn. The morals concern the interpretation and evaluation of arguments in general and the nature and epistemic value of ad ignorantiam in particular. Two theoretical discussions of the argument‐type are next considered, those of Richard Robinson and John Woods and Douglas Walton. I conclude that there is no general fallacy of ad ignorantiam– no argument is fallacious just because it's an ad ignorantiam– and that sometimes no reason is good reason