ABSTRACT
This chapter deals with the usage-based thesis and how this model accounts for knowledge of language (grammar), for how language evolves over time (language change) and for how we gain or acquire our native language (language acquisition). The chapter provides a sketch of the assumptions and theories that characterise this position in cognitive linguistics. One of the central assumptions is that language use is integral to our knowledge of language, our 'language system' or 'mental grammar'. A language user is a member of a particular linguistic community who, in speaking, attempts to achieve a particular interactional goal or set of goals using particular linguistic and non-linguistic strategies. Language use involves both the production of language and the comprehension of language. Models of language processing usually assume a particular model of language knowledge as a starting point, and place an emphasis on experimental methods. The empirical study of language acquisition is known as developmental psycholinguistics.
