 The first doctrine is the ontological primacy of existence (asalat al-wujud), a doctrine that is located within the debate on the Avicennan distinction between existence and essence in contingent beings as seen through the prism of the Sufi metaphysics of ontological monism (wahdat al-wujud). If contingents are composites, then one element of the composition is active and ontologically prior. Is it the case that there are essences in some of being, such as humanity, that wait for a divine agent to actualize and individuate them through the bestowal of existence, an essentialist doctrine that posits a rather paradoxical existence of an essence before it comes to exist? Or as Mulla Sadra suggests, the divine agent produces existences in this world that take on the “garb” of some particular essence. Existence must be ontologically prior not only because of the absurdity of an existence before existence, but also because God is devoid of essence, and his causal link to the world can only be existential if one wishes to avoid the contamination of the divine nature with essences that are composites of different and multiple properties and features. Mulla Sadra uses this doctrine as part of his own ontological proof for the existence of God known as the Proof of the Veracious (burhan al-siddiqin). The monism of the doctrine is expressed in the phrase basit al-haqiqa kull al-ashya’ (‘The simple reality is all things’, a doctrine predicated on the Neoplatonic notion of the simple One): God, the One is simple and pure Being and thus as such is the totality of existence.