 For the regulation of consciences, another standard term was ‘probable certainty’ (certitudo probabilis). Probable certainty forestalled sin by enabling one to base one’s actions on correct probable reasoning. Since reasoning which went beyond the probable was virtually unattainable in many moral contexts, an agent satisfied her or his epistemic duties by relying on sound probable reasoning, thus acquiring a subjective certainty of having done all that could be expected of an agent to avoid sin (Gardeil 1911; Schuessler 2003, 50). In the opinion of many medieval scholastics, probable reasoning could not generate epistemological certainty; the phrase “probable certainty”, however, sprang from compliance with moral demands (which we would call epistemic duties today) and not from strong conviction based on evidence. Perhaps because of the risk of misunderstanding it implied, ‘probable certainty’ was largely supplanted, from the fifteenth century onward, by the similar concept of ‘moral certainty’ (certitudo moralis), (Franklin 2001, 69; Knebel 2000, 55; Schuessler 2009).