It is E. Hocedez' opinion that Aegidius of Rome regarded esse as a sort of perfection which is multiplied in essence and consequently imagined creation as a mutation from potency to act on physical level. But in order to understand properly Aegidius' own intention, the so-called distinctio realis should be exclusively considered with respect to his conception on creation. From this point of view, I analysed so cautiously Aegidius' key-term possibile in his "Quaestiones disputatae de esse et essentia" and "Quodlibeta" that I could point out, in this paper, how Hocedez failed to grasp the true meanings of else and creation in Aegidius ; for according to Aegidius' terminology the word possibile signified ratio and exemplar in divine mind, and Aegidius considered it the indispensable principle for explanation of the fact that the universe is not emanated from God by a natural necessity, but created by divine intelligence and free will.