What is music, and why does it move us? From Pythagoras to the present, writers have struggled to isolate the essence of "pure" or "absolute" music in ways that also account for its profound effect. In Absolute Music: The History of an Idea, Mark Evan Bonds traces the history of these efforts across more than two millennia, paying special attention to the relationship between music's essence and its qualities of form, expression, beauty, autonomy,...