This is the article about constructed languages. For other uses of the term "a posteriori", see a posteriori

A Posteriori

Apart from the album, some additional remixes were released exclusively through the iTunes Store. They are:*"Eppur si muove"  – 6:39*"Dreaming of Andromeda" Apart from the album, some additional remixes were released exclusively through the iTunes Store. They are:*"Eppur si muove" (Tocadisco...

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An "a posteriori language" (from Latin a posteriori - from the later), according to Louis Couturat

Louis Couturat

Louis Couturat was a French logician, mathematician, philosopher, and linguist.-Life:Born in Ris-Orangis, Essonne, France, he was educated in philosophy and mathematics at the École Normale Supérieure...

, is any constructed language

Constructed language

A planned or constructed language—known colloquially as a conlang—is a language whose phonology, grammar, and/or vocabulary has been consciously devised by an individual or group, instead of having evolved naturally...

 whose elements are borrowed or based on existing languages, as opposed to the a priori languages

A priori (languages)

An a priori language is any constructed language whose vocabulary is not based on existing languages, unlike a posteriori constructed languages. Examples of a priori languages include Ro, Solresol, Mirad, Klingon, and Na'vi...

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The a posteriori languages can be divided into three categories:

• Simplified ethnic languages, like Basic English
  Basic English
  Basic English, also known as Simple English, is an English-based controlled language created by linguist and philosopher Charles Kay Ogden as an international auxiliary language, and as an aid for teaching English as a Second Language...
  
   or Latino sine flexione
  Latino sine Flexione
  Latino sine flexione , or Peano’s Interlingua , is an international auxiliary language invented by the Italian mathematician Giuseppe Peano in 1903. It is a simplified version of Latin, and retains its vocabulary...
  
  
• Naturalistic languages, i.e. closest to the real ethnic languages (most often Latin or Romance languages), like Occidental language
  Occidental language
  The language Occidental, later Interlingue, is a planned language created by the Balto-German naval officer and teacher Edgar de Wahl and published in 1922....
  
   or Interlingua
  Interlingua
  Interlingua is an international auxiliary language , developed between 1937 and 1951 by the International Auxiliary Language Association...
  
  
• Autonomous (schematic) languages, in which grammar is a priori but vocabulary is a posteriori, like Esperanto
  Esperanto
  is the most widely spoken constructed international auxiliary language. Its name derives from Doktoro Esperanto , the pseudonym under which L. L. Zamenhof published the first book detailing Esperanto, the Unua Libro, in 1887...
  
   or, to some extent, Volapük
  Volapük
  Volapük is a constructed language, created in 1879–1880 by Johann Martin Schleyer, a Roman Catholic priest in Baden, Germany. Schleyer felt that God had told him in a dream to create an international language. Volapük conventions took place in 1884 , 1887 and 1889 . The first two conventions used...
  
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In distinguishing whether the language is a priori or a posteriori the prevalence and distribution of respectable traits is often the key.