Charting its curious path from the monasteries and universities of thirteenth-century Europe to Silicon Valley in the twenty-first, Duncan uncovers how it has saved heretics from the stake, kept politicians from high office, and made us all into the readers we are today. We follow it through German print shops and Enlightenment coffee houses, novelists' living rooms and university laboratories, encountering emperors and popes, philosophers and prime ministers, poets, librarians and—of course—indexers along the way. Revealing its vast role in our evolving literary and intellectual culture, Duncan shows that, for all our anxieties about the Age of Search, we are all index-rakers at heart—and we have been for eight hundred years.