Double negatives

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 or emphatic negation.Portuguese, Persian, Russian, Spanish, Neapolitan, Italian, Czech, and some dialects of English are examples of negative-concord languages, while Latin and German do not have negative concord. It is cross-linguistically observed that negative-concord languages are more common than those without.

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 affirmation (e.g. "I'm not feeling bad"), an understatement of the positive ("I'm feeling good"). The rhetorical term for this is litotes.

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