 Periphyseon Book One examines the first division, God understood as a transcendent One above, and yet cause of, all creation. God transcends everything; He is, following Pseudo-Dionysius, the “negation of all things” (negatio omnium, III.686d). According to Eriugena—who in this respect is following a tradition which includes Augustine and Boethius as well as Dionysius and other Greek authors—the Aristotelian categories are considered to describe only the created world and do not properly apply to God (I.463d). God cannot “literally” (proprie) be said to be substance or essence (ousia, essentia), nor can He be described in terms of quantity, quality, relation, place or time. He is “superessentialis” (I.459d), a term which, for Eriugena, belongs more to negative theology than to affirmative. His “being” is “beyond being”. Eriugena particularly admires a Dionysian saying from the Celestial Hierarchy (CH iv 1; PG 3: 177d1–2): to gar einai panton estin he hyper to einai theotes (“for the being of all things is the Divinity above being”, III.686d) which he translates as esse omnium est superesse divinitatis, (“the being of all things is the super-being of divinity”, III.686d, I.443b; see also I.516c; III.644b, V.903c). This is perhaps Eriugena’s favorite phrase from Dionysius. (Indeed, Maximus Confessor had also commented on it in I Ambigua xiii, PG 91: 1225d, a passage well known to Eriugena who translated the Ambigua.) Sometimes, instead of invoking the Dionysian formula superesse divinitatis, Eriugena speaks of the “divine superessentiality” (divina superessentialitas, III.634b), or—quoting Divine Names I 1–2 (PG 3: 588b–cb)—of the “superessential and hidden divinity” (superessentialis et occulta divinitas, I.510b).