On 7th May 1777 the enlightened Emperor Josef II, met in Paris Abbé de l’Epée. He teached deaf students in sign language, In his travel journal Josef II. made a note, which has now been discovered for the first time by Herbert Gantschacher in the Austrian National Archives. 1779 Josef II. found a National Institute for Deaf Education. Later judged scholars - e.g. Immanuel Kant - said that sign language is not a language. In 1880, the Milan Congress banned the use of sign language in education. The philosopher Wilhelm Jerusalem and the pedagogue William Stern proved scientifically, that deaf people must be taught with finger spelling and sign language. Once upon a time in the past all languages were equal and once upon a time in the future all languages will be again equal. These original documents are part of a performance of deaf & hearing students from the National Institute for Deaf Education in Vienna and the NMS Markt Allhau in a production of ARBOS – Company for Music & Theatre.