Nancy van Deusen’s The Cultural Context of Medieval Music addresses the mental landscape surrounding music that, especially, was sung and experienced in the Middle Ages. Largely anonymous in its composition, and apparently lacking the motivation of fame and commerce, music within a well thought-out system of education served a purpose that goes far beyond casual entertainment or personal professional advancement. Offering experience through performance, music exemplified the basic principles not only of the material and possible measurements of the visible world—such as of objects, relationships, and movement—but also of the invisible materials of sound and time, making it an ideal medium for working with unseen substances such as concepts, imaginations, and ideas. St. Augustine in the late fourth century reinforced the importance of music for the process of learning when he wrote that nothing could be truly understood without music. This book shows how this, in fact, is the case—a message of great relevance today.