Origins
Historically, a number of factors are found that give rise to prescriptive tendencies in language. Whenever a society reaches a level of complexity to the point where it acquires a permanent system of social stratification and hierarchy, the speech used by political and religious authorities is preserved and admired. This speech often takes on archaic and honorific colours. The style of language used in ritual also differs from everyday speech in many cultures.

When writing is introduced into a culture, new avenues for standards are opened. Written language lacks voice tone and inflection, and other vocal features that serve to disambiguate speech, and tends to compensate for these by stricter adherence to norms. And since writers can take more time to think about their words, new avenues of standardisation open up. Thus literary language, the specific register of written language, lends itself to prescription to a higher degree than spoken language.

The introduction of writing also introduces new economies into language. A body of written texts represents a sunk cost; changes in written language threaten to make the body of preserved texts obsolete, so writing creates an incentive to preserve older forms. In many places, writing was introduced by religious authorities, and serves as a vehicle for the values held to be prestigious by those authorities. Alphabets tend to follow religions; wherever western Christianity has spread, so has the Latin alphabet, while Eastern Orthodoxy is associated with the Greek or Cyrillic alphabets, and Islam goes hand in hand with the Arabic alphabet.[1] Similarly, the prestige of Chinese culture has preserved the usage of Chinese characters and caused their adaptation to the very different languages of Korea and Japan; the prestige of Chinese writing is such that, even when the Hangul alphabet was devised for Korean, the shapes of the letters were designed to fit the square frames of Chinese calligraphy.[2]
Bureaucracy is another factor that encourages prescriptive tendencies in language. When government centres arise, people acquire different forms of language which they use in dealing with the government, which may be seated far from the locality of the governed. Standard writs and other legal forms create a body of precedent in language that tends to be reused over generations and centuries. In more recent times, the effects of bureaucracy have been accelerated by the popularisation of travel and telecommunications; people grow accustomed to hearing speech from distant areas. Eventually, these several factors encourage standards to arise; this phenomenon has been observed since ancient Egyptian, where the spelling of the Middle Kingdom was preserved well into the Ptolemaic period in the standard usage of Egyptian hieroglyphics.[3]

All language in developed societies therefore tends to exist on a continuum of styles. Privileged language is used in legal, ceremonial, and religious contexts, and tends to be prized over local and private speech. Written styles necessarily differ from spoken language, given the different stratagems used to communicate in writing as opposed to speech. Where the discontinuity between a high and a low style of language becomes marked, a state of diglossia arises: here, the privileged language requires special study to master, and is not instantly intelligible to the untrained. The very difficulty of the systems inspires a preservationist urge, since instruction in them represents a large effort. The writer who has mastered Chinese calligraphy or English spelling has put a great deal of time into acquiring a skill, and is likely to resist its devaluation through simplification.[4]