 Probability theory was developed in the early modern period, notably by Huygens and Abraham de Moivre (see Daston 1988). The early eighteenth-century English mathematician, John Arbuthnot, undertook calculations that resembled Neyman-Pearson testing (see Stigler 1986: 226). Hume may have copied this method, as a young admirer of Arbuthnot. Hume’s 100-page essay on population pivoted around the null hypothesis that ancient Rome was more populated than Europe in 1750, and he ably demonstrated that the likelihood that this was the case was vanishingly small. Hume may also have appreciated the insights of Thomas Bayes, who devised his theorem—now known as Bayesianism—in the 1750s, with a posthumous publication in 1764 (see Raynor 1980).