ABSTRACT
This is a tale of two Thomases: Thomas Simpson and Thomas Bayes. Each appears on the mathematical scene, seemingly independently, late in De Moivre’s career. They were both influenced by De Moivre’s work, especially his work in probability and its applications. For his part, De Moivre was unhappy with some of the work of each Thomas, more so that of Thomas Simpson. These are also stories of a connection broken and a connection never made. After a cordial beginning, De Moivre had a distinct falling out with Thomas Simpson. Although he probably knew Bayes, or knew of him, Bayes was apparently never part of De Moivre’s closer circle of friends and colleagues.
