Could a pure sign language society be as advanced as a speaking society?

Question

I remember reading about how a lot of the early paleolithic societies and proto-human species like Neanderthals and Homo Erectus used sign languages before spoken languages. It made me wonder how a society that never developed spoken language would be like.

Let's say that 100,000 years ago, Homo Sapiens dies out but a new species by the name of Homo Mutus takes over. Homo Mutus is very similar to Homo Sapiens. The difference is that they require less food than Homo Sapiens but they also lack a voicebox. Homo Mutus cannot speak, scream, whisper, or make any non-chewing sounds with their mouth.

Can Homo Mutus develop an advanced civilization like Homo Sapiens has without spoken language? Will it be harder or easier to do so with everybody having to use sign language and written languages instead of speaking to get points across?

Answer 1

Sign language can be better

Although there are plenty of situations where sign language would be worse, I think it can actually be better than spoken language.

The idea is that language is required or at the very least boosting a group's ability to advance. This is because the knowledge can spread. As Newton is claimed to once write about his scientific progress: "if I have seen further, it is by standing on the shoulders of giants". The important factor here is that the type of language is less of a factor. We can see in our current society that speech is a definitely great way to spread knowledge and we have done so for millennia. Interestingly it was improved by the written word. But both are still derived from language. In that regard sign language has enough variation and expression to have similar knowledge transfer. Even in this society you can speak volumes by just lifting your middle finger.

The drawbacks are that it is more difficult in groups for example. People need to face the person, as well as see all the different gestures that are made. However, such arguments are easily made from a speaking society. A sign language society could have many advantages compared to the spoken language.

First if all is attention. We can more easily feign attention of listening, while you are much more limited in sign language. This allows for more concentrated 'talking' with sign language. In addition, such a society is more likely to notice a lack of attention, making pauses and breaks important to sign language. They resume when attention can be focused again. This helps in getting a point across better. Teaching might look at a disadvantage, as you can probably service less people in a classroom as a teacher. However, this would lead to more teachers and thus more personal and intensive teaching.

But the shortcomings of language can also increase the importance of language. An example. If you're hunting a large predator or other humans it is extremely important to know what needs to happen beforehand. That means they would improve their language skill as a consequence. Then during a fight where any plan can go right out the door you need to be able to communicate quick and clear what needs to happen. Without a voice and possibly with one or both hands full you would be hampered. So with as few short 'words' you need to be able to communicate. Most probably claps of hands or weapons in certain ways.

Interestingly the best way of communication in many close quarters fighting is silent, often up until the moment you engage.

The language has shortcomings that can be overcome by a surge in communication. This can be compared to an earlier time where many human tribes had a less vocabulary. Out of necessity you create new words to describe and talk. If the necessity is greater there is a larger chance of evolving the language.

That is not to say they will succeed. The shortcomings will at first work against them. It'll take quite some time before it can work in their favour, but at the very least they are more likely to grow their language skills faster than a spoken language out of necessity. At a later time they will reap those rewards.

Answer 2

The more technological a society becomes, the less a spoken language matters

I don't know about you, but the further along my educational road, the less a spoken voice mattered. I had lots of textbooks, research on the Internet, math and graphing programs, circuit design and simulators... Need I go on? Things were already visually symbolic. In fact, here we are sharing ideas with nary a phonon in sight. And those aspects of my education that depended on the spoken word (study groups and lectures) could have been trivially converted to sign language.

I can't think of any reason at all why sign as a primary — or even the sole — language would stop a society from becoming as advanced as any other.

I can tell you one other place it would be an incredible benefit. Sports! Specifically baseball... no more "Hey! Batter, batter, batter!" distractions. I'm right, right?! Think about it.

And now that I think about it, theatre might become visually amazing. We humans pride ourselves in the expressiveness of our dance... but can you imagine how breathtaking a stage production would become? It gives a whole new meaning to "body language."

And what's really amazing is if a soceity evolved based on it, it would be as natural and as capable as any other language. Don't be fooled by what its limitaitons might be compared to our evolution based on sound. Knowing no other way, they would be as capable as we. I wonder how that would affect the development of their peripheral vision?

Answer 3

The only shortcoming I can imagine for a pure sign based language is that it will not allow communications in situation where there is no visibility between the sender and the receiver: for example the darker hours of the night or a situation in which they are not looking at each other.

I think that it is severely limiting: if a bear is attacking you, your and your companion's attention will be focused on the bear, not on your hands so you won't be able to help each other with directions, or if you are walking in line and you are leading the line you have to decide if you want to keep your attention to the path or turn around and talk with your team, nor your followers will be able to warn you of any danger coming from behind. Or during a fight you will have to pick between using your hands for fighting or communicating.

I doubt such a limited communication will help advancing easily.

Answer 4

Sign language is a language

Any transfer of information that happens orally can happen with sign language, new words and grammar can and have been added to sign languages around the world to keep up with modern technology.

Furthermore, the in an advanced modern society most information transfer is written or comes with written components. So speaking versus signing won’t change much.

Again, sign language is a language.

Answer 5

The short answer is: absolutely. For a longer answer it's important to call out that there's likely some unnamed bias in the "as advanced as..." standard, because "advanced" is not a technically specific term.

What would likely happen in the event of a society who, for whatever reason, had no audio-channel means of communication and their primary language was hand-sign, is a divergence of technological development. If you're needing your hands free to speak, things like automation or alternatives to hand-tools become VERY much more important and likely a hard-focus for that society. Communication at long distance will look very different, with SMS or telepresence being likely initial targets.

The advancement of technology is an emergent property of knowledge and communication. But there would be technological sectors that simply held little value for a culture that did not make noises to communicate with one another and so would be considered "primative" or "underdeveloped" by societies for whom such technologies held value.

And on the flipside, there would be technologies that such societies would develop as part of their natural inquiry which would have voice-speaking societies scratching their heads and saying, "They do what with WHAT? HOW?!"

Answer 6

They aren't limited to sign language

Frame challenge: Homo Mutus only lacks a voice box - that does not mean their only option is sign language. Although they could develop a society with only sign language, and probably would use it for their primary language, you have more storytelling options than that.

Sign language has the drawback that you can't yell to get someone's attention, and you can't communicate around corners. Homo Mutus people wouldn't exactly need to do those things, but they would certainly be nice to have, particularly in combat. They aren't deaf, they just lack a voice box.

Therefore, although sign language would be their primary mode of communication, they might use musical instruments to communicate over long distances or when the other party can't be seen.

Horns or drums might be simple, loud, practical options for long-distance communication, particularly in wartime or in the wilderness. (You don't need a voicebox to blow air into a horn; you just need the ability to control your exhalation). They could develop a musical language based on one or more of these instruments, supplementing their sign language. It could be like Morse code. Indoors, people might use it to call people to dinner by clacking a spoon on the wall. Outdoors, they would use proper instruments to call over long distances.

(By the way, what about whistling? You don't need a voice box to whistle, just control over your breathing, tongue, and lips, but it does seem to break the spirit of "Homo Mutus." Perhaps you can just say that they don't have the necessary fine control of their lips and tongue.)

Answer 7

Of course. In addition to sign language, they could also be able to communicate the same ideas we can using instrument base languages like talking drums. Talking drums can allow someone to communicate with someone else over four to five miles away according to the book Interfaces of the Word: Studies in the Evolution of Consciousness and Culture by Walter Ong. There is also Silbo Gomero, a whistling language where people communicate simply by whistling in different pitches and tones at different intervals. People have been able to use it to communicate over distances of four to five kilometers, so even without spoken language, your version of humanity would still be able to communicate for long distances, especially since whistling would not require a voice box: just the ability to blow and properly pucker your lips.

Answer 8

Devil's Advocate answer: No. (Or, only with written language also.)

A lot of answers here are saying yes, and for good reasons. However, to play Devil's Advocate, I believe there's also a compelling case for non-vocal human beings never achieving the same level of advancement.

Sign languages can be equally complex as spoken languages, and the barriers of use in certain contexts are likely not sufficiently high as to make it practically inferior to spoken language. However, spoken language was not by itself what catapulted human beings to the top of the evolutionary ladder. Written language may have been more important.

You could definitely get to the Agricultural Revolution without written language, but I'm not convinced you could get much further than that. You mention Homo mutus uses "sign languages and written languages", and I think it's worth focusing on this second component. Sign language itself is difficult to write down (though there are ways). You could perhaps end up with an ideographic language representing ideas with characters, but language (even written language) is cognitively understood through phonological encoding (or in Deaf people, through an analogous process, which is why finger spelling is important) and thus must fundamentally be structured in a phonological hierarchy.

Keep in mind that what makes human beings advanced is our cooperation. We use stories and collective fictions to surpass the Dunbar Number (the 150 people in a tribe that you can know simply through everyday interactions). We're capable of cooperating with and trusting other human beings in neighboring villages, simply because they share the same beliefs with us and can communicate productively. This is very important. Equally important as shared belief systems is a use of writing far more mundane, and that's record keeping. It's easy to overlook the effect that record keeping has had on civilization, but no sufficiently large and complex political body could exist without the capacity to keep and preserve detailed records. Record keeping, resource tabulation, mathematics, and so forth, are of the utmost importance. An economic system cannot exist without a written language capable of keeping records. Yes, a barter system works to a certain degree, but is impractical when scaling upwards. Small groups can survive with barter alone. For entire civilizations, it is generally beyond impractical. (Barley coin--despite not being a coin--was decently successful in Babylon, and other cultures have used rice and perishable goods as currency, but even this requires systems of measurement and records of transactions and monetary equivalencies.)

In summary, it isn't spoken/signed communication that's important for advanced civilizations (which is not to say it's trivial), it's written communication and record keeping.