 Weakening the ordering axiom introduces the possibility for an agent to forgo comparing a pair of alternatives, an idea both Keynes and Knight advocated (Keynes 1921; Knight 1921). Specifically, dropping the completeness axiom allows an agent to be in a position to neither prefer one option to another nor be indifferent between the two (Koopman 1940; Aumann 1962; Fishburn 1982). Decisiveness, which the completeness axiom encodes, is more mathematical convenience than principle of rationality. The question, which is the question that every proposed axiomatic system faces, is what logically follows from a system which allows for incomplete preferences. Led by Aumann (1962), early axiomatizations of rational incomplete preferences were suggested by Giles (1976) and Giron &amp; Rios (1980), and later studied by Karni (1985), Bewley (2002), Walley (1991), Seidenfeld, Schervish, &amp; Kadane (1995), Ok (2002), Nau (2006), Galaabaatar &amp; Karni (2013) and Zaffalon &amp; Miranda (2017). In addition to accommodating indecision, such systems also allow for you to reason about someone else’s (possibly) complete preferences when your information about that other agent’s preferences is incomplete.