Cognitive semantics is part of the cognitive linguistics movement. Cogitive semantics is typically used as a tool for lexical studies such as those put forth by Leonard Talmy, George Lakoff, Dirk Geeraerts and Bruce Wayne Hawkins. Moreover, cognitive semantic theories are also typically built upon the idea that semantics is amenable to the same mental processes as encyclopaedic knowledge. They thus involve many theories from cognitive psychology and cognitive anthropology such as prototypicality, which cognitive semanticists argue is the basic cause of polysemy.