 The dual definition (and notion) of both being and metaphysics reveals the nuanced univocacy or univocity that rules both Avicenna’s ontology and his theology. If the uncaused Principle is itself part of being, then It is the principle of only part of being: of being insofar as it is caused, and not of all being or of being as such. Indeed, if the Principle were the principle of all being, it would, paradoxically, be Its own principle (while the “First” can be defined only as the being that Itself has no principle at all; the whole as such has no principle: Ilāhiyyāt, I, 2, 14, 1–16,20). Insofar as It is existent, the Principle is thus existent just as the world is. Hence the ontological distinction between the uncaused Principle and Its effect does not lie in existence as such, but in one of its modes: the uncaused Principle is necessary as regards existence, while everything else is always possible as regards existence: i.e., it exists insofar as it is necessitated and therefore necessary by virtue of something other. As a consequence, the existence of things that are in themselves possible is always conceived as related to a (possible) essence, while the being of the Principle is purely and necessarily existence: despite a certain unavoidable ambiguity in Avicenna’s language (see e.g., Ilāhiyyāt, VIII, 7, 363, 1–2; Ilāhiyyāt, VIII, 5, 349, 11: “the reality of the First”), the Necessarily Existent has no essence or no quiddity that differs from existence (anniyya: Ilāhiyyāt, VIII, 4, 344, 10–11; 346, 8–12; cf. Macierowski 1988) and is in that respect beyond essence. The first attribute of the Principle is “that It is and that It is existent” (inn wa-mawǧūd; Ilāhiyyāt, VIII, 7, 367, 12–13): existence is not what It “has”: It simply is.