History of sign language

The recorded history of sign language in Western societies starts in the 17th century, as a visual language or method of communication. Sign language is composed of a system of conventional gestures, mimic, hand signs and finger spelling, plus the use of hand positions to represent the letters of the alphabet. Signs can also represent complete ideas or phrases, not only individual words.

Most sign languages are natural languages, different in construction from oral languages used in proximity to them, and are employed mainly by deaf people in order to communicate.

One of the earliest written records of a sign language is from the fifth century BC, in Plato's Cratylus, where Socrates says: "If we hadn't a voice or a tongue, and wanted to express things to one another, wouldn't we try to make signs by moving our hands, head, and the rest of our body, just as dumb people do at present?"

Until the 19th century, most of what we know about historical sign languages is limited to the manual alphabets (fingerspelling systems) that were invented to facilitate transfer of words from an oral to a sign language, rather than documentation of the sign language itself. Many sign languages have developed independently throughout the world, and no first sign language can be identified. Both signed systems and manual alphabets were found worldwide, and, though most recorded instances of sign languages seem to occur in Europe in the 17th century, it is possible that popular European ideals have overshadowed much of the attention earlier signed systems may have otherwise received. It was commonly accepted, for instance, that “the deaf” could not be educated; when John of Beverley, Archbishop of York, taught a deaf person to speak in 685 AD, it was deemed a miracle, and he was later canonized Generally, philosophies linking (spoken) language and intelligence persisted well into the Enlightenment. Such hegemonic ideas may have prevented the recognition of histories of certain groups for whom sign languages were integral. Earlier than the 17th century, however, groups of Deaf people may have already lived together in communities, where even in small numbers they may have communicated through basic signing systems.

In Native American communities prior to 1492, for instance, it seems one or more signed systems existed as a “lingua franca” which neighboring tribes used to communicate with one another Native American communities believed people born deaf were physically and mentally capable, while people in Europe, starting with the urging of Pedro Ponce de León, would not begin to believe so until the late 16th century. Accounts of such signing indicate these languages were fairly complex, as ethnographers such as Cabeza de Vaca described detailed communications between them and Native Americans that were conducted in sign. A number of Martha’s Vineyard settlers from a community in Kent, England, for instance, seemed to be carriers of deaf genes, leading to a high density of deaf individuals on the island from the 1700s, being the highest around 1840. This environment proved ideal for the development of what is today known as Martha’s Vineyard Sign Language, which was used by hearing and deaf islanders alike. Years earlier, their Kentish ancestors, too, may have had a number of deaf community members and developed their own signing system as well.

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