梅亞述論述祖態，以初始性質為基礎，肯定思維、認知或知識流動可以克服最不利的條件，在一定程度上打破不可共世界的區隔。本文延伸此觀點，說明《天書》與《背後的故事》都涉及意義初始性質的模擬。《天書》透過意義貧乏來「倒推」意義基底尚未進入個人使用，與現世界不能直接溝通的前世界。《背後的故事》則在不同的媒材間延續光影的表達姿態，透過裝置正面、背面並置來呈現意義世界與自己的前世界、次世界如何互相投射。兩個作品都延續了徐冰早期版畫作品所關注的，流動與固定的碰撞與抗衡，並透過表達的表達來聚焦、呈現次世界到臨的必然性。建立在祖態上的跨世界移動是（過去或未來的）新世界到臨在現世界投射出來的痕跡，可以對視野受限的現世界住民形成啟發。這是一個比較貧乏的初始層次，卻保留了「未必不能」的餘地，允許我們由此出發，修造到達次世界的連結。

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.