Dionysian corpus, and much later wrote a commentary on "The Celestial Hierarchy". This constitutes the first major Latin reception of the Areopagite. It is unclear why Eriugena made a new translation so soon after Hilduin's. It has often been suggested that Hilduin's translation was deficient; though this is a possibility, it was a serviceable translation. Another possibility is that Eriugena's creative energies and his inclination toward Greek theological subjects motivated him to make a new translation. Eriugena's next work was a Latin translation of Dionysius the Areopagite undertaken at the request of Charles the Bald. A translation of the Areopagite's writings was not likely to alter the opinion already formed as to Eriugena's orthodoxy. Pope Nicholas I was offended that the work had not been submitted for approval before being given to the world, and ordered Charles to send Eriugena to Rome, or at least to dismiss him from his court. There is no evidence, however, that this order was carried out. At the request of the Byzantine emperor Michael III (c. 858), Eriugena undertook some translation into Latin of the works of Pseudo-Dionysius and added his own commentary. With this translation, he continued in the tradition of St. Augustine and Boethius in introducing the ideas of Neoplatonism from the Greek into the Western European intellectual tradition, where they were to have a strong influence on Christian theology. He also translated St. Gregory of Nyssa's De hominis opificio and St. Maximus Confessor's Ambigua ad Iohannem. De Divisione Naturae Scope of the work Eriugena's magnum opus, De Divisione Naturae (On the Division of Nature) or Periphyseon, is arranged in five books. It has been called the "final achievement" of ancient philosophy, a work which "synthesizes the philosophical accomplishments of fifteen centuries." The form of exposition is that of a catechetical dialogue between a theologian and his pupil, and the method of reasoning is the ancient syllogistic. Nature (Natura in Latin or physis [φύσις] in Greek) is the name of the most comprehensive of all unities, that which contains within itself the most primary division of all things, that which is (being) and that which is not (nonbeing). It is presented, like Alcuin's book, as a dialogue between Master and Pupil. Eriugena anticipates St. Thomas Aquinas, who said that one cannot know and believe a thing at the same time. Eriugena explains that reason is necessary to understand and interpret revelation. "Authority