Dutch Sign Language ( or NGT; Sign Language of the Netherlands or SLN) is the predominant sign language used by deaf people in the Netherlands. Although the same spoken Dutch language is used in the Netherlands and Flanders, the Dutch Sign Language (NGT) is not the same as Flemish Sign Language (VGT). They do have the late 18th-century Old French Sign Language as their common ancestor, but have diverged during the subsequent 200 years, so that mutual intelligibility between modern users has been greatly reduced. History Origins The origins of Dutch Sign Language (NGT) are traceable to Old French Sign Language (VLSF), a term for the sign language that the community of about 200 deaf Parisians used amongst themselves in the mid-18th century. The abbot Charles-Michel de l'Épée wanted to give them religious education, and thus learnt their language, after which he made some adjustments of it himself. Around 1760, he opened a school for the deaf in Paris, the predecessor of the current Institut National de Jeunes Sourds de Paris. Educators from all over Europe came to this and later French schools for the deaf in order to adopt l'Épée's teaching method, and introduce it in their own countries. Therefore, this Old French Sign Language as modified by l'Épée spread across Europe, North America and other continents and became the basis of most modern sign languages, including Dutch Sign Language. The Walloon preacher , born in Blegny, studied in Franeker, and preached in the Walloon church of Groningen since 1777. In 1790, he founded the , the first Dutch school for the deaf, after the example of l'Épée, who he had visited in France. Dialect formation in early schools for the deaf Before the standardisation of the sign language several regional variants were used in the Netherlands and the use of signs was discouraged in order to stimulate deaf people to acquire self-reliance. In the 1900–1980 period, the use of signs was prohibited in education as a consequence of the Milan Conference of 1880. Instead, the oralist method (also called the 'German method') was practiced: deaf people were instructed to learn to speak by imitating hearing people by lip reading, feeling how they used their larynx to make sounds that they were then tasked to imitate. Nevertheless, deaf people continued to use signs amongst themselves, leading to the rise of five dialects within and around the five schools for