
Originally Posted by
2006
Logically "don't say nothing" means 'say something',
It's more a matter of dialect.
unmarked
Don't say nothing.
=> Don't say anything.
marked
Don't say nothing. (That is,) say something.
if there is very heavy stress on "don't" or a specific
plaintive stress on "nothing," then it would be a grammatically correct way of emphasizing that the speaker would rather have "something" than "nothing" at all.
In some languages (or varieties of a language,) negative forms are consistently used throughout the sentence to express a single negation. In other languages, a double negative is used to negate a negation, and therefore, it resolves to a positive. In the former case, triple and quadruple negation can also be seen, which leads to the terms
multiple negation or
negative concord.
Source
Negative concord, popularly called "double negation", as in
I didn't go nowhere; if the sentence is negative, all negatable forms are negated. This contrasts with Standard English, where a double negative is considered a positive (although this wasn't always so; see
double negative). There is also "triple" or "multiple negation", as in the phrase
I don't know nothing about no one no more, which would be "I don't know anything about anybody anymore" in Standard English.
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