Pirahã: a non-Turing-complete human language
newyorker.com
newyorker.com
In his article Mr. Wall says: "So it's rather ironic that my views on Postmodernism were primarily informed by studying linguistics and translation as taught by missionaries, specifically, the Wycliffe Bible Translators. One of the things they hammered home is that there's really no such thing as a primitive human language. By which they mean essentially that all human languages are Turing complete. When you go out to so-called primitive tribes and analyze their languages, you find that structurally they're just about as complex as any other human language. Basically, you can say pretty much anything in any human language, if you work at it long enough. Human languages are Turing complete, as it were."
The former Wycliffe Bible Translator/Summer Institute of Linguistics member Dan Everett reportedly counters this in the New Yorker article. "Everett, once a devotee of Chomskyan linguistics, insists not only that Pirahã is a severe counterexample to the theory of universal grammar but also that it is not an isolated case." This article is fascinating.
My grad school experience is too far in my past to exactly distinguish the nuances between "non-Turing-complete" and "not conforming to Chomsky's universal grammar" -- so have at it discussing the differences. In any case, this article describes a language where it's impossible to describe some common human ideas -- and not through lack of vocabulary, and perhaps not even because of inadequate grammar. Rather, the language betrays a completely different mindset where such ideas may not be relevant to survival.
Dan Everett, former Wycliffe missionary, reached crisis when he found no way to describe the notion of a God or Jesus Christ and their relation to humans to this Amazonian tribe. Mr. Everett decided that if there are people to whom one cannot convey a Christian message, the message must not be universal and cannot be real.
This is an old article, but there are new ones a-comin'; the implications of Dan's work are just starting to be realized.
I'm wondering whether the premise of the language as not Turing complete holds up though. The article claims that the Piraha language lacks abstractions, including counting. Perhaps that could count as incompleteness, but I'm not so sure, and the article doesn't say enough to clear it up. Even if a person cannot use recursive linguistic forms, such as "I saw the dog by the river", they can say, "I saw the dog. The dog is by the river". Can they also say, "Another dog came to the river"? Is that enough context, without tracking the precise count?
Another thought, just because they don't care about a historical fact, is the fact that the story can be told in the language enough for completeness? Even without precise numeric counts?
Does Turing completeness even make sense as a description for a natural language?
Pirahã seems to be a language where expressing certain kinds of complex ideas doesn't work. Sure, one might say "I saw the dog. The dog is by the river." I'm not sure that's the same as "I saw the dog which bit me while I was down at the river yesterday looking for fresh-water oysters to feed my mother-in-law to impress her because she's telling my wife I'm a loser because my alligator hunting sucks." My impression is it's hard to express the latter thought in the language, even breaking it up into separate sentences, without using recursion, which the language lacks, at some point.
Even Everett Says: If you go back to the Pirahã language, and you look at the stories that they tell, you do find recursion. You find that ideas are built inside of other ideas, and one part of the story is subordinate to another part of the story. That's not part of the grammar per se, that's part of the way that they tell their stories. (http://www.edge.org/3rd_culture/everett07/everett07_index.ht...)
As the Harvard people argue, Everett kind-of redefined Piraha Grammar. So there isn't recursion in Everett's official grammar even through the Piraha use recursion in their communication by everyone admission.
"If you go back to the Pirahã language, and you look at the stories that they tell, you do find recursion. You find that ideas are built inside of other ideas, and one part of the story is subordinate to another part of the story. That's not part of the grammar per se, that's part of the way that they tell their stories. So my idea is that recursion is absolutely essential to the human brain, and it's a part of the fact that humans have larger brains than other species. In fact, one of the papers at the recursion conference was on recursion in other species, and it talked about how when deer look for food in the forest, they often use recursive strategies to map their way across the forest and back, and take little side paths that can be analyzed as recursive paths. So it's not clear, first of all that recursion is unique to humans, and it's certainly not clear that recursion is part of language as opposed to part of the brain's general processing.
He says Piraha doesn't have recursion and that he thinks recursion isn't essential to human languages (thus in contradiction with Chomsky theories), but that it's part of how the brain processes information.
Nevins et al. (linked above) note that recursion takes multiple forms in multiple languages and there isn't even anything terribly unusual about the form it takes in Piraha, even if this is a form Everett cannot accept into the grammar.
This seems counterintuitive at first, but logarithms are just ratios and henceforth sometimes actually more useful than ordinal counts - for example, when comparing say, land mass sizes and one plot is 1sq mi larger than the other. Without the context of the size of the plots, this is relatively useless (if they are huge, they're about exactly the same, if one is small then the other is massively bigger). If we say plot B is 1 log unit larger than plot A then it is twice (if base 2) bigger than plot A, no extra context required.
I thought it was cool...
It is very efficient to do calculations logarithmically and evolution appears to have optimized our brains (and that of a few other animals) in this respect.
Then again, we perceive forces, brightness, and loudness logarithmically. (This is not just the subjective experience. The way we are wired to our sound, light, and kinesthetic receptors is indeed logarithmic.) Why shouldn't we also naturally think that way?
EDIT:
Maybe not.
> Gordon ruled out mass retardation. Though the Pirahã do not allow marriage outside their tribe, they have long kept their gene pool refreshed by permitting women to sleep with outsiders.
Unless this mutation is dominant.
> A Pirahã child removed from the jungle at birth and brought up in any city in the world, he said, would have no trouble learning the local tongue.
I wonder if they tried that.
It's important to note that the case of the Pirahã doesn't salvage the Sapir-Whorf hypothesis. Whereas Whorf posited that the absence of a word for a given concept in a language means the people who speak that language cannot think about the concept, the evidence of the Pirahã seems to suggest the reverse: that the reason they don't have words for certain concepts is that they don't think about them.
The Pirahã don't have words for concepts that fall outside their cultural worldview for the simple reason that they have no need of such words.
These people have no art, but they make impromptu sculptures with moving parts and decorative necklaces. They have no use for change and reject all things of the outside world, except for clothing, cloth, thread, machetes, movies, and random strangers, including families who hang around for decades trying to learn their language. They don't point...except maybe with their chins. Their language is strange and unusual - unless it's in a way that casts doubts on Daniel Everett's understanding, like Keren Everett's claims about prosody.
We don't know what these people are saying to Everett, and we have no idea what he's saying to them, due to either deception or a language barrier. Skepticism strikes me as entirely appropriate.
It's just a UI concept, but something I've never managed to get finished.
Talk Description:
http://www.longnow.org/seminars/02009/mar/20/endangered-lang...
Direct MP3 Link:
http://foratv.vo.llnwd.net/o33/mp3/2009-03-20_everett-LNF-16...
According to the article they have been isolated for thousands of years.
Perhaps they don't have the same DNA for language as other humans do. Wikipedia said they don't have the ability to count, even when taught.
http://fora.tv/2009/03/20/Daniel_Everett_Endangered_Language...
In this interview, Everett mentions that he met a 13 year old girl in Brazil who happened in fact to be a Pirahãn—working as a cashier clerk, fully well able to count and do maths.
I can only guess, but I wonder if yours was downvoted for making claims that seem wrong without backing them up - I don't think there is an age when new connections are no longer made nor do I agree that adults can only learn from what they already know - but I wouldn't vote it down because of my disagreement.
Though there has been recent discussion on people voting down purely for disagreement, and that might well violate etiquette. But just <0 without a comment doesn't necessarily do so.
This is why e.g. bilingual kids learn new languages much faster than people who only speak one language, people who learn an instrument as a child can pick up new ones much faster, etc.
What is a personal theory of mine is that if you don't have language to understand a concept by a certain point you can never truly understand it. The only places I point to that support my theory are the few cases of children being raised away from humans [1] and this Pirahã story. It's pretty difficult to prove scientifically since it would require destroying someone's life.
But on this site, of all sites, I would expect discussion about it, not a simple down vote.
[1] I've heard of at least 2 seperate cases where through some odd circumstanced a child reached teenage years without learning any kind of communication with humans. After they were rescued, in both cases they were never able to grasp concepts much further than a young child (around where chimps who learn sign language get to). This is by no means conclusive, since they obviously went through an incredibly traumatic experience, but as I mentioned above, there is no easy way to apply scientific method to this theory.
In this case, it's not about "news," it's about having an intelligent, informed discussion. And interesting stuff that is explained well.
Caveats: Pinker diverges from Chomsky on a lot of things, but he makes it fairly plain what's his and what is Chomsky. Pinker also gets a bad rap (unfairly in my opinion) of being a retrograde right-winger, because of his association with evolutionary psychology.