Civilization in the New World has very deep and ancient roots. The first cities first sprang up in the bone-dry valleys of northern Peru's coast in the 3rd millennium BCE, and then spread along the coast and up into the high Andes, leading to an incredible flowering of different cultures and empires through time. When the Spanish conquistadores encountered the Tahuantinsuyu, known to the modern world as the Inca Empire, they had stumbled upon the most politically sophisticated and technologically advanced urban culture of the New World.
There is still much to be learned about the Incas and their forebearers but one of the most intriguing mysteries is their writing systems, or the apparently lack thereof. Nothing like the written characters of the Old World or even of their distant northern neighbors in Mesoamerica have been recorded by the Spaniards nor discovered in the archaeological record. In other words, according to our definition, Andean cultures never developed writing.
Or did they? One thing appearing in both Spanish chronicles as well as archaeological records is the quipu (also variously written as khipu and kipu), an accounting device based on ropes and knots. A single quipu is often several ropes tied together. At the simplest form, a "main" cord ties a number of "pendant" cords into a unit. This setup can repeat itself up to four levels deep.
The main content of quipus are numbers, which are expressed by knots on a section of rope. Unlike our "Arabic" numbers which uses ten different symbols for each digit (0 to 9), quipu makers tied multiple knots in a tight sequence represent a "digit". Digits can range from no knots (empty space) representing zero, to nine knots representing nine. For example, seven knots in a sequence equals the digit 7.
Multiple sequences of knots represent "digits" that make up a number larger than ten. In other words, quipu was a positional ten-based numeric system that, instead of encoded in written symbols, is encoded in knots. In a positional number system, the position of where a "digit" occurs determines its actual value. For example, in the "Arabic" system, the digit 3 in the number 123 stands for the amount "three" because it is at the very end of the number. Mathematically, 3 x 100 = 3 x 1 = 3. On the other hand, in the number 321 the digit 3 stands for 300 because it is the third to the last digit (3 x 102 = 3 x 100 = 300). The position of the 3 determines its multiplier's exponent.
Similarly, the number 321 would be represented as three sequences of knots, the first one with three knots, the second with two knots, and the last one with one knot. However, there is a twist (pardon the pun). Three different kinds of knots are used in quipu. Commonly, the single knot (S) is used to represent the value of one except in the very last position (or digit). In the last position, two different knot types are used. The figure eight knot (E) represents the value one in the last digit, where as multiple four-turn long knots (L) represent values higher than one in the last position. In other words, the figure eight knot and the four-turn long knot are both used to signal the end of a number.
From Spanish colonial sources, quipu was used as an accounting device employed by the Incan bureaucracy to record amount of goods, animals, and human resources moving through the empire. As such it was never considered a true writing system. However, some recent developments are challenging this notion.
In 1996 a manuscript called Historia et Rudimenta Linguae Piruanorum came to light in Italy among the family possessions of a Naples historian. This document was supposedly written in the early 17th century by Jesuits and contains a fragment of quipu as well as an explanation of how quipu was used to encode spoken language. According to the manuscript, "ideograms" or symbols with well-known meaning from Incan art were used as either phonograms (to represent sounds) or logograms (to denote words).
To represent a sound in this system, a symbol is woven at the beginning of a cord, followed by a number. The symbol is drawn from Andean iconography and would represent a well-known deity or a concept, and the number would point to which syllable of the word represented by the symbol to pronounce. One example given in the manuscript is a symbol for the god Pachamacac, which consists of the syllables pa, cha, ca, and mac. To represent the sound of pa, the quipu maker would weave the Pachacamac symbol followed by a knot for "one", telling the reader to only read the first syllable of the word Pachacamac. It is also possible to represent pa by weaving the symbol of Allpachamasca followed by two knots, meaning the second syllable should be read.
It is also possible to represent a logogram in this system. If the woven symbol does not have any accompanying knots, then the symbol serves as a logogram that represent the entire word of the symbol's meaning. Hence, for example, the Pachacamac symbol by itself on a quipu cord would read as pachacamac.
This system of mixing symbols with numbers does not exactly mean that quipu is a full writing system, since it relies on non-quipu symbols. However, the same manuscript also describes a translation of these symbols to distinct numeric values, meaning that it is possible to completely represent a phonogram or logogram with a group of two quipu numbers.
There is considerable controversy surrounding this manuscript both from its radical claims about well-known historical figures as well as unwillingness of the owner to allow more than one research team to examine and study it. Many well-respected scholars have cast doubt the authenticity of its content. Until substantial and independent studies have been done on this document, its revelations about literary quipu will be dubious.
Puruchuco was a major regional and administrative site in the central highlands of the Inca Empire. During excavations in the 1950's a cache of quipu was discovered in an urn near the ruins of the palace. Its location suggested the house or office of a quipu keeper or quipucamayoq. Recent research into this collection of quipu showed that it contains some form of hierarchical accounting information. Each quipu contains many pendant numeric cords that represent numbers ranging from zero to the thousands. Based on the number of numeric cords, the quipus can be divided into three groups that the scholars labeled levels I, II, and III.
A Puruchuco quipu can be divided into multiple sections based on bigger space between groups of pendant cords. Level I quipus have six sections, level II's have three, and level III's have only one. On all levels, these sections almost always have the same number of pendant numeric cords arranged in the same color pattern, implying that they all record the same set of goods (they may be number of llamas or bushels of corn, but there is no way for us to know). If one adds up numeric cords in the same position across different sections of a level I quipu, the sum is equal or very close to a single numeric cord in the same position in one section of a level II quipu. Similarly, level II numeric cords sum up to a single level III numeric cord. This tells us that the accounting information is being summarized at an increasingly higher level, with the level III quipus most likely representing the grand total of goods from the area administered by Puruchuco. It is very likely that level III quipus were meant to be sent to Cuzco for imperial bookkeeping.
The following example are three segments from a level II cord (UR068) and a segment from a level III cord (UR067), laid out such that the summation of level II numbers match the values in the same relative positions on the level III cord.
In addition, level II and III quipus also have what is called "introductory segments", a number of pendant cords that appear before the numeric cords. In every introductory segment there is always a pendant cord that contains three figure eight (E) knots. If you recall from earlier, figure eight knots can only serve as the number one in the last digit of a quipu number, so a sequence of three figure eight knots is clearly not a number. Instead, it is argued that their appearance on level II and III quipus (which are possibly bound for the central government) imply that the sequence is a "toponym", an place identifier for Puruchuco.
The three figure eight knots representing Puruchuco is the first non-numeric information identified from quipu cords. While it is tempting to claim that this sequence of three figure eight knots is a logogram, we cannot tell if this toponym carries any linguistic value. In other words, the three knots represent the town of Puruchuco, but we do not know if it can also represent the word "Puruchuco". However, regardless of whether the three figure eight knot sequence has linguistic value or not, it tells us that it is quite possible to expect non-numeric and perhaps even non-accounting information encoded in quipu.
It can be established without doubt that quipu was a living and breathing communication system employed by the Inca Empire successfully to keep track of its financial, tributary, and commercial records. However, much remains to unknown and obscure. It might be more than an accounting tool and might in fact be a bona fide writing system, but we are uncertain of what contents are kept within the knots. Quipu research is ongoing and many discoveries are yet to be made, but the pace will be tempered by a lack of a viable "Rosetta Stone". Only time will tell what secrets quipus are holding.