The document discusses 5 popular ideas about language:
1) The prescriptive tradition of grammar rules that tell people how language "should" be used. However, descriptive linguistics objectively describes how language is actually used.
2) Beliefs about language purity and the idea that language decays over time, though linguists see language change as natural and inevitable.
3) Ideas about "primitive" languages and those considered most excellent, though linguists find no objective basis for calling any language superior.
4) Different views on the function of language, which linguists see as serving communication as well as many other social and cognitive purposes.
5) Debates around the relationship between language and thought, which