Anthropological linguist Daniel Everett, who wrote the first Pirahã grammar, claims that there are related pairs of curiosities in their language and culture.[3]
After working with the language for thirty years, Everett states that it has no relative clauses or grammatical recursion. Everett points out that there is recursion of ideas: that in a story, there may be subordinate ideas inside other ideas. He also pointed out that different experts have different definitions of recursion.[5] If the language lacks grammatical recursion, then it is a counterexample to the theory proposed by Chomsky, Hauser and Fitch (2002) that recursion is a feature which all human languages must have.
Pirahã is perhaps second only to Rotokas in New Guinea for the distinction of having the fewest phonemes of any of the world's languages. Women sometimes pronounce s as h, reducing the inventory still further.[4](pp178–179.) Everett states that Pirahã, Rotokas, and Hawaiian each have eleven phonemes. However, the Hawaiian phonology has either 13 or 33 phonemes and it is not known what source or method Everett used when counting the Hawaiian phonemes.[citation needed]
Their language is a unique living language (it is related to Mura, which is no longer spoken). John Colapinto explains, "Unrelated to any other extant tongue, and based on just eight consonants and three vowels, Pirahã has one of the simplest sound systems known. Yet it possesses such a complex array of tones, stresses, and syllable lengths that its speakers can dispense with their vowels and consonants altogether and sing, hum, or whistle conversations."[3] Peter Gordon writes that the language has a very complex verb structure: "To the verb stem are appended up to 15 potential slots for morphological markers that encode aspectual notions such as whether events were witnessed, whether the speaker is certain of its occurrence, whether it is desired, whether it was proximal or distal, and so on. None of the markers encode features such as person, number, tense or gender."[6]
Curiously, although not unprecedentedly,[10] the language has no cardinal or ordinal numbers. Some researchers, such as Prof. Peter Gordon of Columbia University, claim that the Pirahã are incapable of learning numeracy. His colleague, Prof. Daniel L. Everett, on the other hand, argues that the Pirahã are cognitively capable of counting; they simply choose not to do so. They believe that their culture is complete and does not need anything from outside cultures. Everett says, "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."[5]
The language does not have words for precise numbers, but rather concepts for a small amount and a larger amount.
The language may have no unique words for colors. There are no unanalyzable root words for color; the recorded color words are all compounds like mii sai[5] or bii sai, "blood-like," which is not that uncommon.[citation needed]
It is suspected that the language's entire pronoun set, which is the simplest of any known language, was recently borrowed from one of the Tupí–Guaraní languages, and that before that the language may have had no pronouns whatsoever. Many linguists, however, find this claim questionable due to lack of evidence. However, if there had been pronouns at an earlier stage of Pirahã, this would not affect Everett's claim of the significance of the system's simplicity today. There are few Tupi–Guaraní loanwords in areas of the lexicon more susceptible to borrowing (such as nouns referring to cultural items, for instance). There are some loanwords for different types of flora and fauna (which may indicate that the Pirahã came from elsewhere)