Cognitive grammar is a cognitive linguistic theory developed by Ronald Langacker that views grammar as symbolic structures pairing semantic and phonological representations. It considers the basic units of language to be conventional pairings of semantic and phonological structures. Like construction grammar, cognitive grammar views grammar as extending to the entire language. Langacker developed the theory in his two volume work Foundations of Cognitive Grammar. He assumes linguistic structures are motivated by general cognitive processes and draws on principles of gestalt psychology.