Abstract
In Greek mythology, the Muses are not just inspiring agents of poetical creation, but their role is first of all a cosmological one: their birth crowns the process of cosmogony, bringing the world into the manifestation. As we try to demonstrate primarily in the course of Hesiod's Theogony, the song of the Muses celebrates and thus manifests the cosmos or the world-order through its articulation by means of the musical speech.
As the world enters a new domain of appearance, new cosmological categories emerge. The first one being the beauty of the cosmos: as a world-order as well as the ordered whole, it can now manifest itself as beautiful.
The second one being the possibility of fiction, of a delusive appearance: the complex reality can manifest itself in many incompatible ways, partial and thus potentially misleading. The third one being the reflexivity of the cosmos, founded on the reflexivity of the musical speech itself.
The Muses are capable to manifest themselves, and even their own manifestation. By means of their song, the world becomes manifest to itself, too, and the complex system of divine powers gains a reflexive character.
In the closing section, we sketch briefly what happens to this reflexivity in the domain of humans. Indeed, the mortals can gain immortality through the song of the Muses, expressed by inspired poets in human voice.