朱天心的小說〈古都〉描寫台灣解嚴後族群緊張關係的頂點。小說在結尾處描繪納粹「惡的尋常性」，因此似乎指出共群的不可能。但小說主角內在的拉扯以及小說情節的曖昧也讓一些評論家指出，在這不可能之處似乎也存在共群的可能。在西方的討論裡，共群的不可能是現代社會的根本存有基礎，但同時也因共群本質的不在而帶有解放的一面，因此如何從這個基礎出發建立屬於差異年代的不共之共是當代的倫理挑戰。本文訴諸Jean-Luc Nancy與Gilles Deleuze等西方理論家，嘗試釐清小說中共群的複雜面向，並闡述從共群的不可能走向特異共群的關鍵所在。再者，本文透過Deleuze的理論，除解釋小說中記憶與時間的困境外，也嘗試說明，只有在虛實雙破的往返運動中，差異的共同性或特異普同性才得確立並實在化。

Zhu Tianxin’s (Chu Tien-hsin) novella, “The Ancient Capital,” targets on Taiwan’s post-martial-law interethnic relationships which are becoming utterly intense in the 1990s. The depiction of the Nazist “banality of evil” in the ending scene seems to signify exclusively the impossibility of community. However, owing to the internal conflicts of the protagonist and the ambiguities of the plot, critics also identify possibilities of community when it is at its most impossible. Contemporary Western theorists have indicated that communal impossibility is the ontological reality of the modern society and, thanks to the lack of a communal essence, carries emancipatory potentialities on its own. Therefore, our ethical task is to assume that reality and envisage an incommensurable commonality that pertains to our age of difference. Drawing on Jean-Luc Nancy and Gilles Deleuze, this essay purports to explicate the representation of community in Zhu’s story and to clarify how the impossibility of community can lead to a community of singularities. Furthermore, apart from casting light on the dilemma of time and memory in the story, Deleuze’s theory is expounded to demonstrate how the common of the different or the universal of the singular can be established and actualized by dint of a double-disruptive movement enacted between the actual and the virtual.