I use more index cards than anyone I know, and Carl Linnaeus has fascinated me since I first heard of him years ago. So imagine my delight at finding this article: How the index card cataloged the world.

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. But like all information systems, the index card had unexpected political implications, too: It helped set the stage for categorizing people, and for the prejudice and violence that comes along with such classification.

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In 1767, near the end of his career, Linnaeus began to use “little paper slips of a standard size” to record information about plants and animals. According to the historians Isabelle Charmantier and Staffan Müller-Wille, these paper slips offered “an expedient solution to an information-overload crisis” for the Swedish scientist. More than 1,000 of them, measuring five by three inches, are housed at London’s Linnean Society. Each contains notes about plants and material culled from books and other publications. While flimsier than heavy stock and cut by hand, they’re virtually indistinguishable from modern index cards.

The Swedish scientist is more often credited with another invention: binomial nomenclature, the latinized two-part name assigned to every species. Before Linnaeus, rambling descriptions were used to identify plants and animals. A tomato, for example, was a mouthful: Solanum caule inermi herbaceo foliis pinnatis incisis. After Linnaeus, the round fruit became Solanum lycopersicum. Thanks to his landmark study, Systema Naturae, naturalists had a universal language, which organized the natural world into the nested hierarchies still used today—species, genus, family, order, class, phylum, and kingdom. [continue]

How cool is that?

If you happen to wonder why I use so many index cards, take a look at Introducing the Hipster PDA over at 43folders.com. I came across that page years ago, and adopted a variation of that approach for organizing things. It’s not the only method I use, but it is highly useful and satisfying.