Jurisprudence. forthcomingA normative power is the authority to effect a normative change through a declaration of will. This paper uncovers a fundamental asymmetry between potestative concepts (related to normative powers) and deontic concepts (related to duties). The deontic conceptual network consists of three mutually exclusive and jointly exhaustive positions: obligatory, forbidden, and optional. Similarly, the modal network encompasses: necessary, impossible, and contingent. While the potestative network appears to follow a similar pattern – an impression reinforced by the Hohfeldian scheme – it lacks this triangular structure. Overlooking this asymmetry has led several philosophers to adopt unintelligible positions such as the notion of a necessary normative power, where an agent can effect a normative change by exercising their normative power but lacks the power not to do so. I show that this is conceptually flawed. Unlike the deontic may and the possibility can, the normative power can lacks a dual (A and B are duals of each other iff ¬A(¬x) = B(x)). This asymmetry exists because deontic and modal terms are bipartite – relating to action or omission – whereas normative power pertains solely to changing a normative situation, not to refraining from doing so. The extended Hohfeldian framework I propose makes this structural difference explicit. ( direct link )