This essay focuses on two of the modes of existence posited by AIME, a collaborative project comprising Bruno Latour’s monograph An Inquiry into Modes of Existence and a multiauthored website associated with it. I juxtapose the modes of reference [REF] and fiction [FIC] with a famous digression reflecting on historiographical practice in William of Malmesbury’s Gesta regum Anglorum. AIME offers analytical rigor to medievalists’ discussions of the notorious overlap between “history” and “fiction.” William’s bold use of [FIC] to advance [REF] is in the spirit of AIME’s project, though he goes further in trusting [FIC] than AIME is always willing to do. An instance of medieval historiography thus leads the way in overcoming a residual Modern suspicion of a nonreferential mode of existence and of knowledge. Additionally, although AIME’s restriction of crossings to two modes is useful for defining each, in practice more than two are often found “plaited.” I make this argument through a discussion of the use of brackets to mark verse form and rhyme scheme in medieval manuscripts: an example of [TEC•FIC•REF] plaiting. Finally, I call for further development of the multimodal possibilities of “form,” which AIME flags but does not pursue, and for a new mode of existence to be added to Latour’s list: [FOR].