Prometeo (Prometheus) is a 150-minute opera by Luigi Nono, written between 1981 and 1984 and revised in 1985. Here the word "opera" carries the generic Italian meaning of "work," as in work of art, and not its usual meaning. Indeed, Nono scornfully labels Prometeo a "tragedia dell'ascolto", a tragedy of listening. Objectively it can be considered a sequence of nine cantatas, the longest lasting 23 minutes. The Italian libretto, by Massimo Cacciari, selects from texts by such varied authors as Aeschylus, Walter Benjamin and Rainer Maria Rilke and presents the different versions of the myth of Prometheus without telling any version literally.