section_path: Definitions/Mental faculty, organ or instinct
section_name: Mental faculty, organ or instinct
paragraph_text: Mental faculty, organ or instinct
  
  One definition sees language primarily as the mental faculty that allows humans to undertake linguistic behaviour: to learn languages and to produce and understand utterances. This definition stresses the universality of language to all humans, and it emphasizes the biological basis for the human capacity for language as a unique development of the human brain. Proponents of the view that the drive to language acquisition is innate in humans argue that this is supported by the fact that all cognitively normal children raised in an environment where language is accessible will acquire language without formal instruction. Languages may even develop spontaneously in environments where people live or grow up together without a common language; for example, creole languages and spontaneously developed sign languages such as Nicaraguan Sign Language. This view, which can be traced back to the philosophers Kant and Descartes, understands language to be largely innate, for example, in Chomsky 's theory of universal grammar, or American philosopher Jerry Fodor 's extreme innatist theory. These kinds of definitions are often applied in studies of language within a cognitive science framework and in neurolinguistics.