The article by Daniel L. Everett challenges the widely accepted design features of human language, particularly Hockett's criteria of interchangeability, displacement, and productivity, by examining the Pirahã language and culture. Everett argues that these features may be culturally constrained, specifically by the Pirahã practice of limiting communication to immediate, non-linguistic symbols and the mediation of all communication by interlocutors. This cultural constraint explains several surprising aspects of Pirahã grammar and culture, such as the absence of numbers, quantification, color terms, embedding, relative tenses, and complex kinship systems. Everett also discusses the simplicity of the Pirahã pronoun inventory and their lack of individual or collective nouns, art, writing, and drawing. He further notes that despite over 200 years of contact with Brazilians and other non-Pirahã speakers, the Pirahã have maintained their monolingualism in Pirahã. The article concludes that these cultural constraints suggest a need to revise traditional theories of human language design and highlights the importance of considering cultural influences on language and cognition.The article by Daniel L. Everett challenges the widely accepted design features of human language, particularly Hockett's criteria of interchangeability, displacement, and productivity, by examining the Pirahã language and culture. Everett argues that these features may be culturally constrained, specifically by the Pirahã practice of limiting communication to immediate, non-linguistic symbols and the mediation of all communication by interlocutors. This cultural constraint explains several surprising aspects of Pirahã grammar and culture, such as the absence of numbers, quantification, color terms, embedding, relative tenses, and complex kinship systems. Everett also discusses the simplicity of the Pirahã pronoun inventory and their lack of individual or collective nouns, art, writing, and drawing. He further notes that despite over 200 years of contact with Brazilians and other non-Pirahã speakers, the Pirahã have maintained their monolingualism in Pirahã. The article concludes that these cultural constraints suggest a need to revise traditional theories of human language design and highlights the importance of considering cultural influences on language and cognition.