Recursion and human thought

Some things seem conflicting, though. The author says the language lacks numeric system (which involves recursion) and quantifiers, but the people are involved in trade (Brazil nuts for consumables) with other groups (river traders) and believes that they have been doing so for a long time. Puzzling how they could have done this without quantifying !

So I don't think that the fact that they lack numbers is attributable to the linguistic determinism associated with Benjamin Lee Whorf, i.e. that language determines our thought—I don't really think that goes very far. It also doesn't explain their lack of color words, the simplest kinship system that's ever been documented, the lack of recursion, and the lack of quantifiers, and all of these other properties.

.....

The Brazilians the Pirahãs most often see have boats, and they just come up the Pirahãs' river to buy Brazil nuts. In exchange, they bring machetes, gunpowder, powdered milk, sugar, whiskey and so forth. The Pirahãs are usually interested in acquiring these things....They don't accumulate Western goods, but if you've got consumables, the Pirahã might buy, say, two pounds of sugar, pour it in a bowl and eat it all at once. They're not going to put it on the shelf and save it; they'll just eat it when they get it.

Also, I don't understand the "they were sent away" part, in the quote below..

The crucial thing is that the Pirahã have not borrowed any numbers—and they want to learn to count. They asked me to give them classes in Brazilian numbers, so for eight months I spent an hour every night trying to teach them how to count. And it never got anywhere, except for a few of the children. Some of the children learned to do reasonably well, but as soon as anybody started to perform well, they were sent away from the classes. It was just a fun time to eat popcorn and watch me write things on the board.

Who sent them away ? Why ?

> But what if a language didn't show recursion? ... First of all, it would mean that the language is not infinite

A regular language (like a* b) is infinite, but not recursive --- But he's probably not using a mathematical regular expression, but a Chomsky Hierarchy type-3 regular grammar (like A -> aA, A-> b), which is recursive. http://en.wikipedia.org/wiki/Chomsky_hierarchy#The_hierarchy

> Pirahã doesn't have expressions like "John's brother's house" ... you have to say "John has a brother. This brother has a house"

It seems very technical to say that this means the language isn't recursive, because that's only true at the sentence level. It seems to have the quality of recursion, but at the multi-sentence level.

> 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 he agrees. It does seem very limiting to define a language in terms of the sentence structure. There are typical and non-typical ways for sentences to follow one another - surely that's part of the language. Of course, if your discipline has a certain structure for analyzing things (like the Chomsky Hierarchy), it's hard to think outside that structure (and harder to get it published). BTW: I think Chomsky was (and is) brilliant.

> That's one of the strongest Pirahã values; no coercion; you don't tell other people what to do.

> The Pirahã ... in some ways are the ultimate empiricists—they need evidence for every claim you make

I like them