 The distinction between hierarchical and epistemic authority should not be confused with the distinction between external and internal reasons for holding a proposition true. Endoxic probability seems to be entirely based on the opinions of others and thus on external (or indirect) reasons for holding a proposition true. (Internal or direct reasons are those a person herself can assess.) Yet some difficulties with the view that medieval probability was wholly external and thus authority-based deserve to be addressed. Endoxic probability was not the only concept of probability in medieval scholasticism, and others were (as we shall see) more open to internal reasons. Moreover, an expert might claim probability for his own judgment – something not excluded by the definition of endoxon. Nevertheless, agents were often asked to conform to the opinion of a qualified majority (“the larger and more reasonable part”, maior et sanior pars) of competent  evaluators.[18]  This requirement shows that the endoxic understanding of probable opinions was indeed skewed towards external  authority.[19]