Linguistic universal

A linguistic universal is a pattern that occurs systematically across natural languages, potentially true for all of them. For example, All languages have nouns and verbs, or If a language is spoken, it has consonants and vowels. Research in this area of linguistics is closely tied to the study of linguistic typology, and intends to reveal generalizations across languages, likely tied to cognition, perception, or other abilities of the mind. The field was largely pioneered by the linguist Joseph Greenberg, who derived a set of forty-five basic universals, mostly dealing with syntax, from a study of some thirty languages.

Linguists distinguish between two kinds of universals: absolute (opposite: statistical, often called tendencies) and implicational (opposite non-implicational). Absolute universals apply to every known language and are quite few in number; an example is All languages have pronouns. An implicational universal applies to languages with a particular feature that is always accompanied by another feature, such as If a language has trial grammatical number, it also has dual grammatical number, while non-implicational universals just state the existence (or non-existence) of one particular feature.

Also in contrast to absolute universals are tendencies, statements that may not be true for all languages, but nevertheless are far too common to be the result of chance. They also have implicational and non-implicational forms. An example of the latter would be The vast majority of languages have nasal consonants. However, most tendencies, like their universal counterparts, are implicational. For example, With overwhelmingly greater-than-chance frequency, languages with normal SOV order are postpositional. Strictly speaking, a tendency is not a kind of universal, but exceptions to most statements called universals can be found. For example, Latin is an SOV language with prepositions. Often it turns out that these exceptional languages are undergoing a shift from one type of language to another. In the case of Latin, its descendant Romance languages switched to SVO, which is a much more common order among prepositional languages.

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