 Before presenting a reconstruction of Agrippa’s trilemma we need to introduce some definitions. Let’s say that a belief is inferentially justified if and only if it is justified (at least in part) in virtue of its relations to other beliefs. A justified basic belief, by contrast, is a belief that is justified but not in virtue of its relations to other beliefs. An inferential chain is a set of beliefs such that every member of the set is allegedly related to at least one other member by the relation “is justified by”. Agrippa’s trilemma, then, can be presented thus: