Do you know what I think? asks Adrian Leverkuehn. "Musik ist die Zweideutigkeit als System." Music is Janus-faced by its very nature. It can move and paralyze. "What passion cannot music raise and quell," exclaims John Dryden in his Song for St. Cecilia's Day, 1687. Music is an expert in the use of opiates, asserts Settembrini in The Magic Mountain, and Nietzsche speaks of her dual, intoxicating and befogging, nature. Shakespeare's Desdemona "will sing the savageness out of a bear" (IV, i) and the merchants in Novalis' Heinrich von Ofterdingen tell the story of another Orpheus whose song so charms a sea "monster" that it saves the singer's life and returns his treasure to him. John Dryden's Thimotheus "to his breathing flute and sounding lyre, could swell the soul to rage, or kindle soft desire" (Alexander's Feast, 1697). "Musica Consolatrix" and "Musica Tremenda". She is the "Mysterium tremendum et fascinosum" in Kleist's novella about the power of music. While English late 17th and early 18th century literature offers a particularly rich harvest of poetry celebrating the contradictory qualities, or effects, of music, there is in fact testimony to this at all stages of our tradition.