Double negative

A double negative is a grammatical construction occurring when two forms of negation are used in the same sentence. Multiple negation is the more general term referring to the occurrence of more than one negative in a clause. In some languages, double negatives cancel one another and produce an affirmative; in other languages, doubled negatives intensify the negation. Languages where multiple negatives affirm each other are said to have negative concord. Portuguese, Persian, Russian, Spanish, Neapolitan, Italian, Czech, and some non-standard dialects of English are examples of negative-concord languages, while Latin and German do not have negative concord.

Languages without negative concord typically have negative polarity items that are used in place of additional negatives when another negating word already occurs. Examples are "ever", "anything" and "anyone" in the sentence "I haven't ever owed anything to anyone" (cf. "I haven't never owed nothing to no one" in negative-concord dialects of English, and "Nunca devi nada a ninguém" in Portuguese, lit. "Never have I owed nothing to no one", or "Non ho mai dovuto nulla a nessuno" in Italian). Note that negative polarity can be triggered not only by direct negatives such as "not" or "never", but also by words such as "doubt" or "hardly" ("I doubt he has ever owed anything to anyone" or "He has hardly ever owed anything to anyone").

Stylistically, in English, double negatives can sometimes be used for understated affirmation (e.g. "I'm not feeling bad" vs. "I'm feeling good"). The rhetorical term for this is litotes.

When two negatives are used in one independent clause, in standard English the negatives are understood to cancel one another and produce a weakened affirmative: this is known as litotes. However, depending on how such a sentence is constructed, in some dialects if a verb or adverb is in between two negatives then the latter negative is assumed to be intensifying the former thus adding weight or feeling to the negative clause of the sentence. For this reason, it is difficult to portray double negatives in writing as the level of intonation to add weight in one's speech is lost. A double negative intensifier does not necessarily require the prescribed steps, and can easily be ascertained by the mood or intonation of the speaker.

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