Consider the kind of possibility exploited in a rough approximation of Leibniz’s shift argument against absolute space: If absolute space exists, then there is a non-actual possibility, according to which all actual objects are uniformly shifted five feet from their actual spatial positions. Such a possibility—let us suppose—differs only haecceitistically from actuality. (For more on haecceitism and spacetime, see Section 7 and the references therein. On Leibnizian shift arguments, see Russell (2014).)