 Hacking (1975) famously claimed that frequentist conceptions of probability largely arose as a side-product of the seventeenth century revolution in probability. Historians of ideas quickly identified the weaknesses in Hacking’s thesis (Brown 1987; Daston 1988; Garber and Zabell 1979). An understanding of probability as what happens most of the time or for the most part (hōs epi to polu) can already be found in Aristotle and the scholastics. The frequentist notion of probability therefore seems to possess a long pre-modern  history.[20]  Unfortunately, things are far more complicated. Modern frequentism arose as a complex of ideas in the nineteenth century, perhaps evolving only in the twentieth century into a full-fledged conception of probability (Gillies 2000, 88–113). Hence, early modern uses (such as Jacob Bernoulli’s) of the relative frequency of occurrences in a sequence of events are not yet frequentist in the modern sense. Medieval (and ancient) uses of ut frequenter considerations differ, in turn, from early modern (proto-)frequentism (see Schuessler 2019, chap. 12). Having made this point, in what follows, proto-frequentism will be used without the qualification “medieval”.