Much has been written about the question of oral poetry in the earliest attested phases of Greek literature, but not enough attention has yet been paid to the existing internal evidence concerning the authority of actual poetic performance. This essay is meant to highlight this authority and its role in authorisation, that is, in the conferring of authorship. Since the first attested identification of an author in Greek literature takes place in the Hesiodic Theogony, where the figure of Hesiod names himself as the poet of this colossal poem (Hēsiodon, Th. 22), it seems fitting that this very act of self-identification should serve as the focus of inquiry. Further, since the poet defines himself in terms of a dramatised encounter with the Muses, who are represented as giving him the two gifts of a sceptre of authority and poetic inspiration itself, it also seems fitting to take with utmost seriousness the actual wording that describes this encounter. The poet's precisely-worded claim to have received from the Muses the power of telling the absolute truth is key, I shall argue, to his authorship.