When we think, we hear ourselves: this is actually the only thing we are aware of when we think. The deaf from birth would see or perceive (sensations of hands, arms, and face) himself/herself, making those manual signs of the sign language he/she has learned. The thought is rather unconscious: it is behind language, and common to deaf and listeners.
Indeed, all thoughts are based on language. The language supports thinking and gives specific nuances of thought such as abstraction, adjectives, and subtraction that only language can give them: for example, the beauty and lust are abstract words, not all abstract that we can understand, because normal language supports everything that beauty implies.
Do deaf people think in English if they use sign language and if they read English? How could they do that if they have never heard the words that they turn into signs and read? Maybe they’re just visualizing words instead of hearing them?
More generally, can we think without language?
- A person who became deaf at a late age: they will think in the language learned during their childhood.
- A person born totally deaf:it is preferable that their deafness is detected during the first 21 and 36 months, critical period during which the babies easily acquire the fundamentals of the language, thus creating in their brain the cognitive infrastructure essential for communication. Too late a diagnosis of deafness, for example at school, can lead to severe learning difficulties, even if the child’s intelligence is quite normal. If deafness is detected early enough, the deaf child will be able to acquire a sign language instead of an oral language.
A Natural Language
Sign language (SL) is a natural language, it has been formed and evolved gradually over time and has been transmitted culturally from generation to generation. Natural languages are contrasted with constructed languages (such as Esperanto, programming languages and mathematical languages), which, in turn, have been intentionally formed by a man with the aim of fulfilling a specific need.
The different sign languages are not adaptations of oral languages, they are natural languages that have evolved in their own way. In fact, Sign language is somewhat closer to Chinese (a sign to represent a word/phrase) than to English.
A Universal Sign Language?
There are several sign languages (there are apparently 121), depending on the country, the region (dialects)…for example, American Sign Language differs much more from English sign language than from its oral equivalent. We see that at international events that bring together deaf people from different countries, we need sign language translators.
In the same way that we have created an international and universal oral language like Esperanto, there is an international equivalent for sign language called the gestuno (International Sign Language). In both cases, success has been relative…English has established itself as an international oral language and in the case of the deaf, American Sign Language is mainly used.
Sign language offers its users the ability to manipulate symbols, capture abstractions, and actively acquire and execute knowledge. In other words, sign language helps young children learn to think in sign language. Exactly the same thing that happened to us as children when we were learning to communicate orally in our mother tongue.
It may also be useful for a deaf person to learn the oral and written language in order to be able to read on the lips of the other person, read various signs and indications, read books, follow subtitled films.
There is a debate about whether deaf babies should be offered strictly oral, sign language or bilingual education. What we have seen is that a deaf child who learns our language afterward will become bilingual, but will continue to think in sign language. In the same way, when he sleeps, he will codify his dreams in signs. It can happen that a deaf person in his sleep occasionally gesticulates with signs of his tongue.