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, although references to forms of communication using hand gestures date back as far as 5th century BC Greece. 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.
Development of sign language
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?"The next earliest use of sign language was recorded in 60 A.D. The first chapter of the Gospel of Luke relates that the angel Gabriel rendered Zacharias, the father of John the Baptist, unable to speak because of his unbelief. In Luke 1:62 it is recorded, "And they made signs to his father, how he would have him called." The word "signs" in this passage is translated from the Greek word, enneuo, meaning: to nod at, i.e. beckon or communicate by gesture—making signs. There are two additional recorded references of a similar Greek word found in the New Testament in John 13:24 and Acts 24:10.
In the Middle Ages, Monastic sign languages were used by a number of religious orders in Europe. These were not true "sign languages", however, but well-developed systems of gestural communication. Moreover, they did not take vows of total silence - despite popular belief, vows of total silence were only developed by some orders starting in the 17th century. The Rule of St. Benedict only forbid conversation in certain parts of the monastery or during certain hours of the day.
Until the 19th century, most of what we know about historical sign languages is limited to the manual alphabets 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, Bishop of York, taught a deaf person to speak in 685 AD, it was deemed a miracle, and he was later canonized Generally, philosophies linking 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.
Even earlier, between 1500 and 1700, it seems that members of the Turkish Ottoman court were using a form of signed communication. Many sought-after servants were deaf, as, some argue, they were seen as more quiet and trustworthy. Many diplomats and other hearing members of the court, however, also learned and communicated amongst one another through this signing system, which was passed down through the deaf members of the court.
In 1620, Juan Pablo Bonet published Reducción de las letras y arte para enseñar a hablar a los mudos in Madrid. It is considered the first modern treatise on phonetics and speech therapy, setting out a method of oral education for deaf children by means of the use of manual signs, in the form of a manual alphabet to improve communication with the deaf. It is suggested that Pedro Ponce de León developed the first manual alphabet from which Juan Pablo Bonet based his writings.
In Britain, manual alphabets were also in use for a number of purposes, such as secret communication, public speaking, or communication by deaf people. In 1648, John Bulwer described "Master Babington", a deaf man proficient in the use of a manual alphabet, "contryved on the joynts of his fingers", whose wife could converse with him easily, even in the dark through the use of tactile signing.
In 1680, George Dalgarno published Didascalocophus, or, The deaf and dumb mans tutor, in which he presented his own method of deaf education, including an "arthrological" alphabet, where letters are indicated by pointing to different joints of the fingers and palm of the left hand. Arthrological systems had been in use by hearing people for some time; some have speculated that they can be traced to early Ogham manual alphabets.
The vowels of this alphabet have survived in the contemporary alphabets used in British Sign Language, Auslan and New Zealand Sign Language. The earliest known printed pictures of consonants of the modern two-handed alphabet appeared in 1698 with Digiti Lingua, a pamphlet by an anonymous author who was himself unable to speak. He suggested that the manual alphabet could also be used by mutes, for silence and secrecy, or purely for entertainment. Nine of its letters can be traced to earlier alphabets, and 17 letters of the modern two-handed alphabet can be found among the two sets of 26 handshapes depicted.
Charles de La Fin published a book in 1692 describing an alphabetic system where pointing to a body part represented the first letter of the part, and vowels were located on the fingertips as with the other British systems. He described codes for both English and Latin.
By 1720, the British manual alphabet had found more or less its present form. Descendants of this alphabet have been used by deaf communities in former British colonies India, Australia, New Zealand, Uganda and South Africa, as well as the republics and provinces of the former Yugoslavia, Grand Cayman Island in the Caribbean, Indonesia, Norway, Germany and the USA.
In France, the first sign languages developed in the 18th century. Old French Sign Language was used in Paris' deaf community, before l'Abbé Charles Michel de l'Épée started his deaf school in 1760 in Paris. L'Épée's lessons were based upon his observations of deaf people signing with hands in the streets of Paris. Synthesized with French grammar, it evolved into the French Sign Language. Laurent Clerc, a graduate and former teacher in Paris, went to the United States with Thomas Hopkins Gallaudet to found American School for the Deaf at Hartford.
The 18th permanent school for the deaf was established in Hartford, Connecticut; others followed. In 1817, Clerc and Gallaudet founded the American Asylum for the Deaf and Dumb. In 1864, a college for deaf people was founded in Washington D.C. Its enabling act was signed by Abraham Lincoln and was named "The National Deaf-Mute College" in 1986.
In the 21st century, various Christian organisations have been in the process of translating parts or all of the Bible into at least one sign language using videos. In February 2020, Jehovah's Witnesses released a complete Bible translation in American Sign Language.