A posteriori (languages)

An "a posteriori language" (from Latin a posteriori - from the later), according to Louis Couturat, is any constructed language whose elements are borrowed or based on existing languages, as opposed to the a priori languages.

The a posteriori languages can be divided into three categories:

• Simplified ethnic languages, like Basic English or Latino sine flexione
• Naturalistic languages, i.e. closest to the real ethnic languages (most often Latin or Romance languages), like Occidental language or Interlingua
• Autonomous (schematic) languages, in which grammar is a priori but vocabulary is a posteriori, like Esperanto or, to some extent, Volapük.

In distinguishing whether the language is a priori or a posteriori the prevalence and distribution of respectable traits is often the key.

References

• Louis Couturat, Les nouvelles langues internationales. Paris: Hachette. 1907. With Léopold Leau. Republished 2001, Olms.
• Louis Couturat, Étude sur la dérivation dans la langue internationales. 1910. Paris: Delagrave. 100 p.