Rereading Bernoulli

Abstract

Recalling the correspondence between Jacob Bernoulli (1654-1705), and Gottfried Wilhelm (von) Leibniz, the Author stressed the logic problem of statistical inductions and the role of prior and posterior probabilities. The probability of a phenomenon is derived from the number and weight (that is the evidential force) of matters demonstrating its existence. In turn, the weight of matters, hence the probability deriving from it, is derived from the ratio of only favorable cases to favorable and contrary cases, all of them being considered as equally possible, because, if they are not so, they can be made such by counting a case that has a greater opportunity to occur a number of times proportional to such opportunity.