Formed on the plane of primary qualities, ancestrality, as proposed by Quentin Meillassoux, ensures that certain cognitive exchanges can take place across the severest kind of barriers, partially overcoming the divide between incompossible worlds. This article argues that this account of primary qualities can help us explain how two major works on media and mediation by the artist Xu Bing, A Book from the Sky and Background Story, are built upon the simulation of such qualities. A Book from the Sky explicitly impoverishes meaning by regressing from actual usage to a pre-world of primitive signifying elements. Background Story extends expression by projecting light across incompatible media, simulating partial communication between a world and its preceding and succeeding worlds across transformative, possibly impoverishing“advents.” Such concerns hark back to Xu’s early print works which gesture toward the necessity of the advent of the new by underscoring the negotiation between fluidity and fixity, binding the volatility of such negotiation to the felt need for expression to express itself. Such art confirms that ancestrality supports transmission between worlds by leaving footprints of possible advents on the existing world, offering inspiration for its inhabitants who are otherwise unable to penetrate the walls of the intra-world. Thus, while ancestrality impoverishes meaning, it also activates hopes for becoming and enrichment, enabling us to imagine new ways to await the advent of the new.