Amateur Scientist Leland Locke and the Inca Khipu

Khipus (or quipus) are ancient systems of knotted cords used by the Incas for accounting and other purposes. One early Spanish writer wrote that the Incas could read the patterns of knots on the strings. But the full meaning of khipus is still in dispute.

The typical khipu consists of a horizontal cord from which are suspended up to hundreds or even a thousand separate cords. The suspended cords contain various patterns of knots.

The first major breakthrough in decoding the Khipu was made by historian L. Leland Locke in the 1920s. He proposed that the knots on Khipu strings were similar in function to the beads of an abacus. A recent news article in the journal Science reports that Locke was also an amateur scientist (Charles C. Mann, Unraveling Khipu's Secrets, Science 309, 1008-1009, 12 August 2005).

In the 1970s, Cornel University historians Robert and Marcia Asche reviewed Locke's findings. They assembled a major database of khipu information and suggested that the knots of khipus form a kind of written language. Nevertheless, about 80 percent of khipus fit Locke's criteria for accounting.

The latest paper on khipus is by Gary Urton and Carrie J. Brezine (Khipu Accounting in Ancient Peru, Science 309, 1065-1067, 12 August 2005). This paper discusses the accounting connection of ancient Peruvian khipus they studied. The 21 khipus they studied appear to be census and tax records.

The interpretation of khipus is a potential research topic for some sharp amateur scientists who would like to continue in the tradition of L. Leland Locke. The web has many fine articles about khipus. There are also many photographs. As ably demonstrated by Locke, khipu interpretation does not require a specialized degree in mathematics or linguistics. A dedication to the task and considerable study and patience are required.

Forrest M. Mims III