This paper deals with the particularities of vagueness in law. Thereby the question of the law’s capacity for vagueness is closely related to the question of the impact of vagueness in law, since exaggerated vagueness combined with the elasticity of legal interpretation methodology may affect the constitutional principles of legal certainty, the division of powers, and the binding force of statute. To represent vagueness and the instability of legal concepts and rules, a Hyperbola of Meaning is introduced, opposing Heck’s metaphor (...) of a core and a periphery of meaning. Furthermore, evidence is provided that the use of vague legal concepts and the capability of legal methodology to affect the specific meaning of those concepts, may give rise to astonishing and irrational changes of meaning of the law. Finally the paper sets out in search of an added value of vagueness in law, and weighs several stated pros and contras of vagueness. The paper is written against a background of the German speaking realm. (shrink)