Dialects are regional varieties of a language that differ in vocabulary, pronunciation and even grammar. Like accents, dialects are all equally correct in their own varieties and there isn’t an absolute dialect which the others are inferior to from a linguistic perspective.
Accent and vocabulary differences are apparent to all and I think they are more commonly acceptable. If grammar deviates from the standard dialect though, it is outright deemed incorrect. A lot of people would consider the sentence He be working ungrammatical, however linguistically we can’t say that there is anything wrong with this utterance, it’s perfectly fine in a non-standard dialect, the African American Vernacular English (AAVE), where its use is systematic and consistent. We could translate it into Standard English as He works.
One of the dialects gains a social and political advantage and becomes more prestigious than the others. It becomes the dialect of education, administration, the media and this is the dialect that is taught to students of the language. It is now no longer just any regional dialect, it’s associated with high social class and education. Conversely, the other dialects are looked down on and deemed “incorrect” even though from a linguistic perspective their status is completely accidental.
So is the standard dialect considered the language or language is the umbrella term that encompasses all the dialects? Where does a dialect end and a langauge begins? It would be tempting to consider two dialects as one language if they are mutually-intelligible, but we’d have problems with that definition. There are a bunch of Chinese dialects and their speakers don’t understand each other even though they all speak Chinese. Slovaks and Czechs understand each other yet they speak two different languages, Slovak and Czech. So, it’ easy to see that the concept of a language is a social construct and not a scientific term. It is said that „a language is a dialect with an army and a navy”.
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