How Complex Can a Sign Language Get?

Question

In this setting, I have a species with incredibly weak vocalization abilities, being hardly able to speak over what a human would consider a whisper. In this, they have relied entirely on using their hands to speak their dominant languages. Some are assisted by other parts of the body or elements of body language, but hands maintain a mostly-universal method of communication within their cultures.

Since they are, at the time I am currently concerned with, at an FTL-level of technology, how complex might their sign language get after thousands of years of development and evolution? Writing could also be a subject of intense complication, as it has no need to actually be vocalized (human languages are literally constructed and organized around how we vocalize) and only translatable into physical sign (who needs syllables? or syntaxing? or even discernable letters?).

Some basic information that could possibly be relevant: This species is called the Shovan, an exonym given by their long-time brethren, the Scien. They live in wet and hot tropical climates primarily, being cold-blooded and thus unfit for the frozen worlds of the Scien. They have 5 digits on each of their two hands, as well as two legs and a clearly discernable head structure that features a large bony frill. Their scales feature intricate and colorful patterns, especially in their youth. They are on average moderately shorter than a human, but the digits on their hands are slightly (5-7 cm / 2-3 in) longer.

As always, all answers are appreciated and any needed clarification will be given ^^

Answer 1

EXTREMELY COMPLEX

Spoken language is limited by only producing a single sound at a time (though with plenty of variation in pitch, intonation, loudness, etc.).

With sign language (using two five-fingered hands), you have two hands that each can show a different hand gesture at the same time, and you can move or position the hands (and elbows) in various ways do add further meaning to the hand gesture.

Hand gestures can include bending and strecthing the individual fingers at various degrees. With just three positions per finger, for ten fingers that comes to 59,049 variations, each of which could have a different meaning. In addition, pairs of fingers could be spread, held close or crossed, and streched fingers could be held straight or turned down. Even without moving or positioning hands, this roughly triples the meaning of each finger, for more than 3 billion meanings for hand gestures alone. Position and movement (e.g. wagging a finger) probably brings it close to a trillion - far more than a human mind could ever hope to grasp.

To this we can add body language, which humans use to modify or add to the meaning of speech (nodding, shaking your head, swaying, leaning forward or away, standing spread-legged or leaning on one foot, and much more).

For your aliens, their frills could add to the meaning: Is it laid back, straight up, tilted to a side, changing color or whatever. Movable ears can also add meaning - just look at cats or rabbits. The sign language could also be accented with grunts, whistles or whatever sounds the species can produce.

All in all, sign language can be far more complex than simple spoken language. The limitations are not what it is possible to express with sign language, but what you are capable of understanding.

Also worth noting is that sign language is severely limited in darkness, which spoken language is not. Distance can also hamper sign language more than speech - it can be difficult to discern details. Your aliens have probably developed a simpler sign language for long-distance use, using only only arm movements. In return, sign language is silent, which can come in handy (just see any action movie), and noise doesn't disturb it.

Answer 2

I'd think, from what I've read on sign language, and my experience with a sister that studied some ASL, that you could have just as much variety in sign language as you could with spoken language.

Our perception of sign language may rank it lower than spoken languages (not sure if that wording makes sense) because things like ASL are purposefully constructed forms of communication - thus we feel like they might have limits imposed upon them by their artificiality.

But strictly speaking, the ability to vocalize different sounds, while complex, is still limited - and most languages don't try to use them all - for example, many languages don't have the "th" sound at the start of "the." English doesn't use the glottal stop except in rare cases like "uh-oh."

Sign language has limitations as well, but a great number of options too. You might see really interesting variations along with culture. Perhaps everyone carries around certain items that assist them in communicating something - holding up a blue stone means that you are speaking in a joking tone, while a green stone means a serious one.

The possibilities are really expansive.

Answer 3

As others have said, signed languages can be at least as complex as spoken languages, and potentially much more complex given the ability to communicate multiple things simultaneously and depict actions in 3D.

For example, while watching a signed translation of the book My First Peek-a-boo Animals by Eric Carle, I saw a fluent ASL signer sign tree with one hand and then the other to depict two trees, and then turn one hand into a movement classifier to depict an animal swinging from the location she'd signed the first tree and land on the arm that was still signing the second tree. What a vivid and descriptive way to communicate "this animal swings from tree to tree"!

Regarding writing, real-life signed languages usually borrow their writing system from spoken languages, and a lot of people erroneously think it's impossible to write sign languages, but it's totally possible. There are several phonetic writing systems available for signed languages - for example, Sutton SignWriting and Stokoe notation are two such systems. None have gotten widespread use for cultural context reasons, mainly because Deaf people are a minority group who will need to learn to read and write in a manner understandable to the surrounding hearing majority, and also because access to video recording has predated writing for signed languages. But in a society where spoken language isn't used, it'd be very different.

In fact, writing might even be easier for a signing culture to invent. After all, the earliest forms of writing were pictographs. In the written forms of many spoken languages, pictographs depicting various things ended up associated with sounds present in the words for those things, eventually leading to syllabics, alphabets or abugidas. (Chinese is a notable exception for sticking to pictographs, possibly because they were writing for an empire full of mutually unintelligible languages, many of them logographic and tonal.) The earliest writing for a signing society might also be pictographic, but instead of having to draw the meaning, they could literally draw what someone signing that word looks like.

Over time, the drawings will become so stylized that an untrained reader couldn't even tell what they originally represented, just like most people nowadays don't look at 'A' and think of an antelope. However, the connection between meaningful parameters of the signs and distinct symbols in the resulting text would be retained and learnable.

I mentioned sign parameters above. They're basically the sign language equivalent to phonemes. But whereas phonemes are single, sequentially produced sounds, sign parameters come in five types - handshape, location of hand, movement of hand, orientation of hand, and nonmanual markers (communicative signals made with other body parts besides the hands, such as a pursed lip and furrowed brow to signal that you're asking an open-ended question.

Not all of these parameters necessarily have to be written, just as we don't necessarily have to indicate tone of voice or vocal emphasis when writing most spoken languages, but in cases where it's essential to understand the meaning of a statement, they'll probably mark it some way. For example, in ASL you might lose some nuance by not recording facial expressions, but you don't actually need to know they furrowed their brow and pursed their lips to know that "you name what" is an open-ended question. Or, some parameters might end up being treated more like their equivalent to punctuation rather than letters. There are a lot of ways to approach this, depending on the specific language and culture of your aliens.

One thing is certain - if they're high-tech, they will undoubtedly have multiple ways to digitize their language to communicate long-distance, including new communication methods that only work with technological assistance, such as how many people in our world communicate online with meme pictures. It'd be fascinating to think of how such technology would combine with a sign-centric linguistic culture.