 Rudolph Agricola, another humanist innovator, put the word probabilis center stage in his path-breaking reinterpretation of dialectic. For him, dialectic was the art of speaking with probability on whatever issue. This definition appears traditional enough, but Agricola (De inventione dialectica, 210) explicitly distanced himself from Aristotle’s endoxon as the basis for probability in dialectic. As has been noted by modern scholars, “speaking with probability” is a feature of a process for Agricola rather than one grounded in a property of propositions used in a dialectical syllogism. Probability arises from the argumentative quality (argumentosus), aptness (aptus), and fittingness (consentaneus) of a reasoning process (Agricola, De inventione dialectica, 210, 306; Mack 1993, 170; Spranzi-Zuber 2011, 89). This directs dialectic away from the reliance on authority implied by Aristotle’s definition of reputable opinion. It is also significant that Valla and Agricola focus on the production of conviction (fides) instead of mere opinion. They thus seem to call for more rhetorical persuasion or for higher epistemological standards in dialectic’s quest for truth. It is difficult, however, to develop an uncontentious interpretation of what Agricola exactly meant by his peculiar, but undoubtedly influential, view of probability. In sixteenth-century century humanist discourse on probability, Agricola’s dialectic was a key innovation, as were the new interest in Aristotle’s Topics, the rise of a Protestant tradition of dialectic, and much more. Together with advancements in early modern scholasticism, these developments provide a justification for ending the present survey around 1500.