Incas Used Binary?

Abhijeet Chavan writes "An article in the Independent reports that a leading scholar believes the Incas may have used a form of binary code 500 years before computers were invented. 'Gary Urton, professor of anthropology at Harvard University, has re-analysed the complicated knotted strings of the Inca - decorative objects called khipu - and found they contain a seven-bit binary code capable of conveying more than 1,500 separate units of information...If Professor Urton is right, it means the Inca not only invented a form of binary code more than 500 years before the invention of the computer, but they used it as part of the only three-dimensional written language.'"

Comments

Re:7 bits?

[Anonymous Coward]

From the article:

In a strict seven-bit code this would give 128 permutations (two to the power of seven) but Professor Urton said because there were 24 possible colours that could be used in khipu construction, the actual permutations are 1,536 (or two to the power of six, multiplied by 24).

Re:7 bits?

[arth1]

Using 24 colors seems rather stupid to me. What if you're out of pigment #21? And what about when it's dark and you have to use artificial lights (read: torches) -- will you be able to tell that a dot is burgundy and not brown?

Occam's razor dictates that the professor is wrong.

Anyhow, archeologists a few thousand years from now will probably look at an old copy of WIRED and say the same thing about us.

Regards,
--
*Art

Old news

[de la mettrie]

This is not new. It has been generally surmised that quipus (khipus, qipus) served as a carrier of complex informations. See e.g. this page for pictures and info.

According to the article, the quoted scientist merely says that the permutations possible in a quipu weaving might indicate a septary (not, by any means, a binary) code. He also says he's looking for a Rosetta stone equivalent.

Well, do go on looking, old fellow. But I wouldn't hold my breath waiting for a whip-toting archaeologist-hero to stumble out of a collapsing jungle temple with a quipu-to-English dictionary under his arm. Remember, the Incas were one of the more institutionally stupid (and thus, extinct) civilizations in history - after independently inventing the wheel, they used it for children's toys exclusively.

And he expects to unearth the original quipu RFC? It's probably in quipu, too. And eaten by a llama.

Re:7 bits?

[ozbon]

Considering we're talking about a society/civilisation from 600 years ago (minimum) I don't think artificial light (other than fire) was really an issue.

And if you're out of pigment #21, just make some more. (At a guess)

Not 1500 units of information

[p3d0]

After multiplying the different permutations of the knots, they reach the conclusion that there are 1536 possibilities, and then go on to state that "This could mean the code used by the makers allowed them to convey some 1,536 separate units of information".

That is a poor interpretation. 1536 possibilities allows someone to encode 10.6 bits of information. To encode 1536 "separate units" of information, each unit must represent no more than 1/145th of a bit. That is a very, very small amount of information, equivalent to having someone tell you something you were already 99.5% sure was true, such as "wow, this poker hand is not a straight!" or "guess what, my birthday this year does not fall on Friday the 13th".

It may be closer to the truth to say their knot language had 1536 different symbols, as compared with the 50-or-so letters, numbers, and punctuation marks we use in English.

Incas used base 10

[UCRowerG]

According to this website (thank you, Google), Incas used a base 10 system for numbering, while all their neighbors used base 60. If this is true, I would venture to say that the 7-bit quipu system was just large enough for their other records, same as the original 7-bit ASCII was for the standard western alphabet.

I also found more detailed information on quipus, if anyone is interested.

Re:"before computers"?

[bj8rn]

using the invention of computers as your compare date makes little sense

Makes just as much sense as comparing all dates to the birthday of one Jesus, son of Joseph the carpenter. It's just an arbitrary point in time that is supposed to demonstrate something. Relating the time to George Boole's accomplishment would have been more informative, that's true, but I don't think most of the people even know who Boole was, not to mention when he lived (I don't know when he lived. 19th century?). Hell, not too many people know when the first electronic computers were built, either, but they have more clue about it than Boole.

Re:Analysis

[AlecC]

Each separate knot has six variables with two possible values (I gave three from memory, there are three more) and one with 24 values - colour. Therefore each knot represents a kind of "super byte" which can hold a single value from 0 to 1535. The data is not in the string but in the joins between strings. From a base string, there are multiple strings, with each not having 1536 possible values. From each string, substrings, sub-sub-strings and sub-sub-sub strings may be appended. Each append operation adds another "superbyte". The number of strings is indetermiante, because, as the article says, effectively the data spreads out in 3-space.

Of course, I don't reckon they used it to maximum density, and the use of the bits may well have been representational. But it might be that it in facts encodes a chapter/paragraph/sentence/word structure. Simple sentences ("Fred owes Bill 5 goats") would be base plus one level of attached strings - a fairly simple level of encoding, with a super-byte at each knot. But it would not be diffcult to generalise from this onec it became common. In fact, this would tend to happen automatically if Bill tied all his IOUs onto one "backing string": from spine, substring identifies debtors, sub-substrings identify multiple debts.

Re:Not unique

[bj8rn]

An interesting thing is how the existence of writing in South American civilizations seems to be connected to their attitude towards the Spanish. The Incas had quipus, Aztecs had pictogrammatic writing, Mayas had some kind of early-stage phonetic alphabet. When the Spanish came, the Incas were certain that they were gods; Aztecs believed it in the beginning, but later realised that the Spanish are humans just like themselves. Mayas raised the question, then answered it negatively and never called the Spanish gods.

The possible explanation is, that the evolution of writing is affected by the evolution of mental structures and categories: the Incas saw everything unfamiliar as supernatural, having been isolated from other cultures. The Aztecs and (particularly) the Mayas had had contacts with other cultures besides their own, so they know what it means to be conquered by a more advanced civilization.