String Theory

Question: What ancient civilization with no written language used “quipus,” an intricate system of knotted strings, as a form of communication to rule over their vast empire?

Answer: The Inca

Anthropologists and archaeologists are always arguing about how we should define “civilization.” They usually cite things like the wheel, draft animals, and a written language as minimum requirements to be classified as an “advanced” civilization. 

Well, the Incas had none of those.

Yet by the time the Spanish arrived at their borders in 1528, they had established the largest and most technologically advanced society in the Americas—an empire that stretched for more than 2,500 miles from modern-day Colombia all the way down to Chile. From a single valley, the Inca governed a vast realm of some 12 million people of various cultures and languages living in some of the most mountainous terrain on Earth. And they didn’t know how to write. Or did they?

Archaeologists have deciphered the numerical values encoded in quipus.

The Incas adopted a unique system of recording information called “quipus” (“knots” in Quechua), a system of knotted strings that stored data and communicated information. They weren’t the first to adopt this method. Cultures across the ancient Andean world used this system for thousands of years. And for the Incas, quipus were a necessary and effective universal method of communication with people who spoke different languages in the vast empire they ruled over.

The quipu allowed the Inca to carefully track and keep records of everything from the amounts of troops to stores of food and other goods that moved through their vast empire.

It may have looked like a meaningless tangle of strings and knots, but the arrangement of quipu was extremely precise and quite sophisticated, communicating everything from accounting figures to field measurements to genealogy. When the Inca were expanding their empire, the first thing they did was send down their “accountants” to take inventory of a newly conquered territory’s resources—streams, fields, fishing, mining, population census, and more—all carefully recorded on a quipu and brought back to Cusco. Now they could make an informed decision on how best to administer their new land.

A rare surviving quipu on display at the Amano Museum of textiles in Lima.

So important was the information that was to be gathered by the quipu, those “accountants” the Incas relied on were actually a specially trained caste called quipumayuq, or the “keepers of the quipus,” whose responsibility was tying and translating the quipus. And it certainly sure worked out well for them. Even Francisco Pizarro and his Spanish conquistadors were impressed. While it was the gold and treasure they were after, once they began to impose their own customs on the crumbling Inca empire, they were said to be simply awestruck at how efficient their society had been organized.

So were quipus just a primitive counting tool to store numerical data, or were they something more? Unfortunately, after the Spanish took over, just a tiny percentage of Incan quipus survived. And in a century of study, while no one has been able make them “talk,” it’s looking more and more like quipus do hold a lot more information than a bunch of numbers—in fact, they may be encoding long lost stories, Incan myths and legends, songs, and more.

The first hint that a quipu wasn’t just some dressed-up abacus came from a 1609 account by  Garcilaso de la Vega, son of an Inca princess and a Spanish conquistador. He wrote how the Inca had “an admirable method of counting everything in the Inca’s kingdom, including all taxes and tributes, both paid and due, which they did with knots in strings of different colors.” But what followed is the important part. He went on to say that the Incas “recorded on knots everything that could be counted, even mentioning battles and fights, all the embassies that had come to visit the Inca, and all the speeches and arguments they had uttered.”

De la Vega may have been embellishing, but what he was saying is that quipus contained similar narrative information that other cultures write down—and that’s a written language. It doesn’t really matter, though. Enough new information has come to light in recent years to make us reconsider everything we know about Incan history and culture.

So, the Inca may have had a written language after all. But they definitely didn’t have the wheel.

Wait, they really didn’t have something as basic as the wheel?

It had long been assumed that Incas—and a few other ancient civilizations—didn’t use wheels because they didn’t know how to make them. But that’s simply not true. Archaeologists have unearthed plenty of examples of wheeled toys across Mesoamerica. We’re sure you’re familiar with the expression “necessity is the mother of invention.” Well, the Inca had no need for wheels or wheeled carts. They certainly had the technical savvy to invent them, but why bother? What were they going to use to pull something on wheels? All the horses, cows, and oxen were across the Atlantic.

Another factor was geography. Draft animals or not, no wheeled wagons were going to traverse up and down the steep terrain of the Andes, along narrow footpaths, and across suspension bridges swaying in the wind. The wheel may have been responsible for dramatically accelerating the progress of civilizations across Eurasia—making it easier to travel long distances—but it was impractical for the Inca.

They had no trouble maintaining communications along a stretch of more than two thousand miles without wheels. Human couriers and llamas did the job just fine. It’s the same for the ancient Polynesians, who didn’t have the wheel either. Most of the traveling they did was across the water—which was much easier in canoes.

A few more fascinating facts about quipus and the Inca

• Faster than Amazon Prime—The Inca went to great lengths—literally—to transport quipus back to Cusco. Looping the cords over their shoulders, messengers (called chasquis) would run several miles at the fastest pace possible, then pass off to a fresh chasquis, until the information finally reached the emperor’s hands.


• Roadrunner—Chasquis messengers transported their quipus along the Royal Road, the main thoroughfare through the empire. Stretching more than two thousand miles, it was the longest road in the world until the 1800s. Most sections were twenty-four feet wide, lined with shade trees, with a canal to provide water for chasquis and other travelers.


• Water under the bridge—The Royal Road took messengers over mountainous terrain that often required the construction of suspension bridges across steep river gorges. The Inca bridges were held together with woven grass, which had to be replaced every two years. The last remaining Inca bridge, called Queshuachaca, straddles a river high in the Andes. The local populace gathers to replace the bridge’s woven grass ropes each year.


• Like a calculator, but knot—As far as recording numbers go, quipus were based on the decimal system. The arrangement of three different types of knots reveals its numerical value—the “single knot” represent tens, hundreds, thousands, and ten thousands. The “long knot” represents two through nine. And the “figure eight knot” represents number one.


• No habla “quipus”—The Spanish knew about Incan quipus, but didn’t understand them. Assuming there was something “ungodly” about them, they had them all burned. At first, quipus had to be dug out of graves in order to display them in museums. It wasn’t until the end of the 19th century that scholars began to realize that their only opportunity to learn about Incan culture would be to preserve the knowledge encoded in quipus.


• Typical college slacker—By comparing six 17th-century quipus with a Spanish census document, a first year Harvard student made a significant breakthrough in the field by noticing how each cord in the quipus corresponded to and revealed the social status of the 132 people recorded in the census record. He also discovered that the way the knots were tied denoted the first names of each person. And he did this all over Spring Break.


• Counting sheep—The quipu is still used by some Andean and South American communities, especially by shepherds as a method to track their herds of sheep and goats.


• Dyed in the wool—The cords of quipus are crafted from llama or alpaca wool, and sometimes cotton. Colors of the cords indicate a specific item or activity that is being (agricultural, military, engineering, etc.). Natural dyes extracted from leaves and insect were used to color the quipu


• Who you callin’ Inca?—The Incas didn’t refer to themselves “Incas.” “Inka” was just the name of their leader at the time. It would be like calling all Egyptians “Pharaoh.” The Spanish chose to call the entire culture “Inca.” The actual name of the empire was the “Tawantinsuyu,” or “Land of the Four Corners” because it was formed when four tribes came together.

Explore the legendary lands of the Inca during Machu Picchu & The Galápagos.