Early bookkeeping may have been language Of all the major Bronze Age civilizations, only the Inca of South America appeared to lack a written language, an exception embarrassing to anthropologists who habitually include writing as a defining attribute of a vibrant, complex culture deserving to be ranked a civilization. The Inca left ample evidence of the other attributes: monumental architecture, technology, urbanization and political and social structures to mobilize people and resources. Mesopotamia, Egypt, China and the Maya of Mexico and Central America had all these and writing too. The only possible Incan example of encoding and recording information could have been cryptic knotted strings known as khipu. In the conventional view of scholars, most khipu (or quipu, in the Hispanic spelling) were arranged as knotted strings hanging from horizontal cords in such a way as to represent numbers for bookkeeping and census purposes. The khipu were presumably textile abacuses, hardly written documents. But a more searching analysis of some 450 of the 600 surviving khipu has called into question this interpretation. Although they were probably mainly accounting tools, a growing number of researchers now think that some khipu were non-numerical and may have been an early form of writing. If khipu is indeed the medium of a writing system, Dr. Gary Urton of Harvard says, this is entirely different from any of the known ancient scripts, beginning with the cuneiform of Mesopotamia more than 5,000 years ago. The khipu did not record information in graphic signs for words, but rather a kind of three-dimensional binary code similar to the language of today's computers. Each sequence could have been a name, an identity or an activity. With the possible variations afforded by string colors and weaves, Dr. Urton estimated, the khipu makers could have had at their command more than 1,500 separate units of information. By comparison, the Sumerians worked with fewer than 1,500 cuneiform signs, and Egyptian hieroglyphs numbered under 800. A creator of khipu, Dr. Urton posits, made a series of choices involving the type and color of string and each knot. Each choice contributed to creating a binary signature. A certain string configuration could represent signs that stood for a value, object or event, much as graphic signs do in familiar forms of writing. Emboldened by this insight, Dr. Urton said that the Inca “may well have been recording full subject-object-verb notations in the khipu.” Abridged from an article by John Noble Wilford, The New York Times, August 12, 2003