Dialects—The Standard as Token of the Past

Languages typically change quite quickly: there are cases where linguists examine a language at one point only to find that 60 years later, it has morphed into practically a brand new one. However, when a dialect of a language is used widely in writing and literacy is high, the pace of change is artificially slowed because people come to see “the language” as on the page and inviolable. This helps create diglossia: standard Arabic is based on the language of the Koran, while the colloquial Arabics went on with natural change.