Interlinguistics of interlinguistics are, however, not so constructive, but rather descriptive, comparative, historic, sociolinguistic, or concerned with translation by humans or machines. As for Esperanto, which is the most widely used constructed interlanguage, there is a relatively abundant literature about the language itself and its philology (see Esperantology). Only a few of the many constructed languages have been applied practically to any noteworthy extent. The most prosperous were Volapük (1879, Johann Martin Schleyer), Esperanto (1887 Ludwik Lejzer Zamenhof), Latino sine flexione (1903, Giuseppe Peano), Ido (1907, Louis Couturat), Occidental-Interlingue (1922, Edgar de Wahl) and Interlingua (1951, IALA and Alexander Gode), with
Ludwik Dorn Ludwik Dorn Ludwik Dorn (, born 5 June 1954 in Warsaw) is a Polish conservative politician, former Deputy Prime Minister and member of Sejm elected on 5 November 2007. He was born Ludwik Dornbaum, to Jewish parents, Henryk Dornbaum, a socialist activist and Alina née Kluger, a doctor. All of his father's family was murdered during the Holocaust. In the 1960s Dornbaum family changed their name to Dorn. He was raised agnostic, but he converted to Roman Catholicism at the age of 51. From 31 October 2005 to 7 February 2007 he was Minister of Interior and Administration, resigned after