Commenting on Friedrich Schlegel and the romanticist concept of irony, in his doctoral thesis Walter Benjamin (1919) introduced the notion of formal irony. Unlike subjective irony, formal irony is not bound to the abysmal boundlessness of the romantic critic; it does not simply cancel itself out as Hegel argued. Rather, formal irony designates an objective activity within the work of art itself. In other words, formal irony is not simply negative or self-annihilating but designates the positive feature of constructing through destructing. This sort of non-nullifying nihilism functions through the enactment of a Nichts, a nihil that is operative within aesthetic formations. Without ever arriving at the zero-level of all formations, this nothingness persists as unstable movement, deviation, or displacement. It is the inexhaustible movement of voiding without forming a void. In this respect, it presents a strictly relational concept, an unstable yet non-nullified nothingness that never dissolves itself fully, never perishes completely but keeps on building through demolishing, forming through deforming, enhancing through reducing, fulfilling through voiding. In my presentation, I examine the structure of these paradoxical formulae and discuss how they could provide the key to a positive concept of nihilism.