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Why Sign Language is Not Universal:

By: Nicoletta Berti

November 8th 2023

It is not uncommon to see astonishment when the hearing person finds out that there are different sign languages: American Sign Language, Italian Sign Language, French Sign Language, the more recent Nicaraguan Sign Language…and so on. The question punctually arises: Since these languages are based on signing, why is there not a universal one? The reason lies in the true nature of sign languages: they are, as their name suggests, languages.

William Stokoe (1960), in his Sign Languages Structure: An Outline of the Visual Communication System of the American Deaf, started a revolution by establishing for the academia that languages used by Deaf people had an origin, development, and status equal to those heard worldwide. To answer that sense of astonishment, it will be presented how sign languages cannot be universal because they do not escape the biological, evolutive, and historical components enclosed in the nature and etiology of all human languages as they are legitimate languages from all points of view.

The Biological Aspect:

Developmentally, in hearing children, spoken gestures and language are related as supporting each other until they divide and take different functional paths. Gestures support spoken words independently from the physical presence of the interlocutor and, most of the time, taken separately, do not reflect the content but the tone of the communication. Deaf children share with their hearing counterparts the first universal phase. Still, they part as the symbolic content and abstraction needed to convey more complicated communications cannot be expressed using their voice.

The observation of an individual from birth to language development seems to pinpoint some crucial phases that also reveal what and when the presence of hearing caregivers (and other socio-historical events) marks the path toward talking or signing (or both) (Cardona & Volterra, 2013, pp. 117-131). The baby's first gestures are more understandable than the vocal ones: around nine months, the child starts using intentional gestures to communicate with caregivers. Such gestures (leaning toward an object with the straight arm, holding and showing an object in their hands, pointing to the object/person, and switching eyes from the interlocutor to the object/person they are willing to address the attention to) are called “performative” or “deictic” because they are part of a willingly and meaningful motion (Carbona& Volterra, p.p. 120-121).

After the first year of age, the gestures become more symbolic because they refer to something else, to concepts or objects that are not concretely present but exist in abstraction: they mimic driving to refer to a car, the swing to refer to dancing, or holding an imaginary phone to mimic a conversation (Cardona & Volterra, 2013, pp.121-122). Progressively, children attribute to those gestures a symbolic nature and refer to those concepts when the object is not present or is not the focus of the conversation: they mimic the gesture of driving while pronouncing words recalling the situation (“wroom wroom” in English, “broom broom” in Italian) until they use such an abstraction to refer to them without those being in context.

This decontextualization that happens between nine and sixteen months of age is accompanied by vocal attempts, and usually, parents pay more attention to the words than the gesture. Slowly, the child learns to use words without supporting the concept with a gesture, and around fifteen-sixteen months of age, the number of words is higher than the gestures. This is when the child develops the faculty of using gestures and words that do not convey the same meaning: they mimic the glasses and say nonna, accompanied by a gibberish word, to refer to their grandmother’s glasses. Depending on the environment, the child will keep learning words and abandon the associated or supportive gesture. When children are exposed to both languages, sign and vocal, they will learn both precisely as they would if exposed to two different spoken languages, Spanish and English, for example. They will also learn when to use one or the other based on the person with them or the environment (Cardona &Volterra, 2013, pp.124-125). Therefore, depending on the community in which the child is raised, the prevalent language – the one that is more useful to know in terms of survival - will stick and develop. 


The Evolutive Aspect


Sign languages satisfy the intrinsic need to understand each other to survive and strive as human beings. As gestures part at a crossroads of the hearing child's evolution, becoming the supportive elements of talking, sign language parts from those gestures as the Deaf baby learns how to express deeper concepts and more abstract ideas. As words were chosen to represent the reality experienced by hearing individuals belonging to the same group by manipulating sounds and agreeing on the symbolic correspondence between concept and object, gestures among Deaf individuals developed to satisfy the same necessity. Human beings evolved from communicating through gestures to using words under the development of the anatomical conformation of the speech-producing apparatus conferring the capacity to produce sounds structured in conventionally meaningful syllables (Cardona & Volterra, 2013, pp.64-65). In an informal phylogenesis-ontogenesis association, it is legitimate to suppose that, as the hominids developed a way to produce meaningful words, they dropped gestures as their primary communication method. Babies growing up among hearing adults substitute gestures with words as they grow up. Nevertheless, gestures shared by the first hominids and babies belong to a different communication level than sign language. Homo Sapiens remains testimony that they could not produce words as we know them. It is then inferred and studied that the first form of interaction must have been through gestures understood among the same group. Some gestures can be considered universals (as there also are abstractions and behaviors according to Kant) when they are based “on the physics and geometry of the real world” (Wilbour, as cited in Napoli, 2011, p.893). Such gestures are those pantomimes that can be shared among all human beings because they refer to actions that inevitably everyone must accomplish to stay alive. A gesture that mimics eating, drinking, sleeping, and other essential functions is understandable not because it belongs to a universal language but because it refers to universal functions. Sign languages maintained such gestures within their lexicon, not to formalize a universal, but to keep what comes spontaneous to the Deaf and the hearing people alike. There is no reason why a language would create some distance between onomatopoeic sounds or instinctual gestures: the new forced suggestions would inevitably fall under a sort of natural selection. This is because of the physics and geometry of the real world visually showing through many signs (for example, attributes to the same word appear in the same spatial area, no matter the language), for the innate nature of gesture (present even in people who speak on the phone, when such movements cannot convey any extra support to the interlocutor) and the strong instant connection that is established between two Deaf people. Not all deaf people want to belong to the Deaf community, but in difficult times, the shared experience that comes with being the minority in a world conceived for hearing people prevails and helps establish a connection that could be, hypothetically, a fundamental liaison to figure out whether an environment is hostile or benign.


The Historical Aspect


Deaf individuals went across centuries of marked solitude, oppression, and abuse, and sign language represented their highest form of adaptation in terms of survival. Since signing was repeatedly forbidden and stopped from becoming a formal language, it lagged from when it was an adaptive communication system to when it was recognized and taught. The incommunicability and presence of sounds that could not be morphed into words gave the impression that these children were also cognitively impaired. In the past, a deaf child was perceived as an ill child. They were restricted from being part of society until the eighteenth century, when scholars finally recognized their intelligence and abilities. Such countless forms of oppression did not allow sign language to earn the early formal institution as a language. This affected the perception of hearing people and still partly explains the common surprise when discovering that there is no universal sign language. This never stopped Deaf children from finding someone to interact with and create a secret language. Still, society had to wait until Abbé De l’Epée to see children being taught sign language. Abbé De l’Epée was using “signs naturels” (accepted home signs, those more universal), “signs methodiques”(signs connected with the grammar of that specific language), and “signs conventionel” (signs coined borrowing from other languages or by using a logical connection with current society)(Stokoe, 1960). For example, masculine signs were around the eyebrows because of the typical gesture of males touching the hat brim, and feminine signs were around the cheeks because the visible part of women's hair was around that height. This first structured and methodical sign language was mainly a tool to teach French. There was an attention to verbs and articles to teach proper grammar. Slowly, with Abbé Sicard, sign language became a more intrinsically functional language not necessarily meant to teach oral grammar. Laurent Clerc was a pupil of Abbé Sicard, and, as history reveals, he played a fundamental role in creating the American Sign Language with Thomas Gallaudet (Stokoe, 1960). With positive evolutions recognizing sign language as a language and some bumps in which the Deaf were forbidden from signing, sign language evolved into a formalization in which some parts of the speech were not useful to convey the message, as for the copula of the verb. With time, nonfunctional parts of speech disappeared, and it was clear that some grammatical parts were missing because of the natural evolution of signing into a language with its properties and specificities (Valade, as cited in Stokoe, 1960).


Shared Aspects of Different Sign Languages


At this point, it is clear how biological and historical reasons explain the lack of universality in sign languages. They follow the same developmental milestones and the similar destiny of a spoken language. As every language reflects the community, region, and country of origin and development, so does every sign language present in each society. Deaf individuals have additional reasons that historically pull them together, giving the false impression that they can communicate easily across countries. Mainstreaming, oralism, prestige, oppression, customs, and written language also impacted each sign language's evolution (Napoli, 2011, p. 893). This is why, even within the same country, signs differ slightly, but interestingly, this makes them similar on a powerful and beyond language level. As Chinese and American speakers are put together in a room without any technology, the Deaf from the two countries will start understanding each other and share a common language much faster than the two people tied to their oral customs (Cardona & Volterra, 2013). Still, this connection and flexibility shown between Deaf individuals from different countries should not be misinterpreted as the existence of a universal sign language: the universality stops as it stops among hearing people. The shared historical experience of an oppressed cultural group creates a unity that can be misinterpreted as universality.




As sign language is a form of communication used by a group of people exposed to the same historical and geographical environment, sharing a similar experience in the social world, there is a lack of universality as seen in spoken language. Although there are differences in the degree of incommunicability between hearing individuals from different countries and Deaf ones from other countries, there is reasonable evidence supporting the natural development of sign languages with specificities belonging to distinct groups and geographical areas. As writing is now widespread compared to the past centuries and technology facilitates translations, visual communications, and simultaneous chatting, society is becoming less and less prerogative of hearing people. The first years of a human being play a crucial role in determining the ability to be part of both worlds (spoken and signed) and to grow up with the identity of an individual belonging to a cultural minority. There is a commonality among sign languages, but also among all languages because of innate and universal traits intrinsic to human biological, evolutive, and historical components. These traits testify that we are all human beings from the same soup of genetic mapping, living in the same world. Even considering the hypothesis that sign languages may have a fast lane toward universal communication, they are still far from being a universal form of communication because each language encloses the story of its specific cultural group.



Cardona, T. R., & Volterra, V. (2013). Le lingue dei Segni: Storia e Semiotica. Carocci.


Napoli, D. J. (2011). Sign Languages (review). Language, 87(4), 890–894.


Stokoe, W. C. (1960). Sign language structure: An outline of the visual communication systems of the American deaf. Journal of Deaf Studies and Deaf Education, 10(1), 3–37.



 For more papers on similar topics see:


Chinese Sign Language


International Sign Language


Cite article:


Berti, N. (2023, November 8). Why Sign Language is Not Universal. The Lifeprint Library. ASL University.


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