includes the possibility that the thoughts of the speakers are influenced by their language in various ways as well. Whether or not Pirahã lacks recursion remains a topic of intense debate and linguistic determinism has been widely criticized for its absolutism and refuted by linguists.

One such argument comes from Michael Frank et al. who continued Daniel Everett's research and ran further experiments on the Pirahã published in "Numbers as a cognitive technology," and found that Everett was wrong, the Pirahã did not have words for