 Interestingly, omnism has typically been assumed in the literature. It may have only operated as an unquestioned background assumption until the groundbreaking work of Bergström (1966) and Castañeda (1968). Goldman (1978) and Bykvist (2002) defend distinct variants of maximalism. Since then, there have been a few arguments against maximalism (cf. Gustafsson 2014). Omnism seems to be considered the default position, though new arguments against omnism and in favor of maximalism have started to appear in the literature recently (Portmore 2017a,b, forthcoming; Brown 2018). Much of the debate revolves around theProblem of Act Versions. Following Brown (2018: 754) and Portmore (forthcoming: ch. 4), this problem may be explained by considering the following three jointly inconsistent principles.