'Musica est optimum': Martin Luther's Theory of Music

Martin Luther’s appreciation for music as a practical instrument to promote the message of the Reformation by the creation of vernacular hymnody and specifically Lutheran liturgical music has dominated studies of Luther and his music. His systematic understanding of music, on the other hand, has been consistently neglected. This article argues that more than twenty years into his Reformation the philosophical basis of his music theory remained very much indebted to Johannes de Muris’s influential Musica speculativa and later humanist interpretations. Consideration of this relation sheds light on Luther’s understanding of music as a quadrivial art form and the queen of philosophical learning.