How the Index Card Cataloged the World

The Library of Congress card for Walt Whitman's Leaves of Grass.
"Like every graduate student, I once holed up in the library cramming for my doctoral oral exams. This ritual hazing starts with a long reading list. Come exam day, the scholar must prove mastery of a field, whether it’s Islamic art or German history. The student sits before a panel of professors, answering questions drawn from the book list. To prepare for this initiation, I bought a lifetime supply of index cards. On each four-by-six rectangle, I distilled the major points of a book. My index cards—portable, visual, tactile, easily rearranged and reshuffled—got me through the exam. Yet it never occurred to me, as I rehearsed my talking points more than a decade ago, that my index cards belonged to the very European history I was studying. The index card was a product of the Enlightenment, conceived by one of its towering figures: Carl Linnaeus, the Swedish botanist, physician, and the father of modern taxonomy. ..."
The Atlantic
W - Index card
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