Why you should learn sign language

Link post

Sorry if this is somewhat off topic, but I have a small dream of sign language becoming a rationalist shibboleth and serving as a jumping off point for sign to spread more in society at large. I know this is pretty unlikely, but it seems worth a shot. I gave a presentation on it at a LessWrong Community Weekend, and people seemed interested. Sign language is also super intellectually interesting in its own right and is a very fun learning experience! Anyway, on with the show.

(EDIT: A few extra notes based on comments. First, I actually think ASL is pretty easy to learn from the video lectures I link below. I did okay in a one-on-one conversation with a deaf person after that. Second, you’ll obviously have to weigh up if learning to sign is worth it for you. I have just tried to argue that it’s more useful and enriching than you might otherwise have thought. Finally, this mostly is just a Neat Thing. The only “rationalist” aspects would come from an interest in learning neat things, and my argument that society would be better optimized if everyone knew how to sign. Sorry again for being off topic.)


I’ve been learning sign language for four years now, and I swear it’s fun like nothing else in the world. At the risk of projecting my interests onto others, I’d like to make the case for learning to sign. I’ll focus primarily on American Sign Language (ASL) since it’s what I know, but most of what I say should generalize to other sign languages too.

If you want to learn ASL, I highly recommend Dr. Bill Vicars’ materials here. Vicars has a PhD in deaf education, is deaf himself, and has published his core ASL 1 − 4 lectures online, plus much more, free of charge. He is seriously excellent.

What is sign language anyway?

First, I should explain what sign language is. The basics are probably pretty clear: it’s a language where you communicate using the shape and movement of your hands, rather than spoken or written words (although really other body parts are involved too, like facial expressions). So that’s what sign language is. But more importantly, what is it not?

ASL is not a conlang. Conlangs (or constructed languages) are purposefully invented and planned for some purpose, such as Esperanto for international communication, or Lojban for unambiguous communication.

While we’re at it, ASL is not a code for English. For example, Braille is a writing system in which an existing language is encoded into tactile form. There is even such a thing as Signed Exact English, which directly encodes each English word into a sign and maintains all the same grammatical structure. But ASL is not like these.

Furthermore, ASL is not universal. When people first learn a bit more about sign, they are very commonly surprised that, for example, Britain and America have totally different sign languages. And there’s a certain feel-good, hippy-dippy meme that, like, there can only be one sign language, man. Cuz it’s just pictures, man. I mean it’s just the symbols for the thing. It transcends language. How could there be more than one? (Someone has said this to my face.) The only problem is that it’s not true.

Instead, ASL is a natural language. It developed organically among deaf people attempting to communicate with eachother. Historically, Britain’s first school for the deaf was founded in 1760, and America’s in 1817. Before such schools, deaf people were largely isolated from any sort of deaf community, leaving little opportunity for language to develop, beyond some home sign[1] and occasional village sign[2].

With the American revolution taking place in 1776, we can see these two sign languages must have developed independently. On reflection, then, there’s no good reason to expect them to be similar. In fact, ASL has its roots in French Sign Language. The French teacher Laurent Clerc helped found America’s first school for the deaf and teach its first students. These students brought their own home and village signs, and through this language contact, ASL was born.

Why sign language is different

Confession: I don’t really care about languages. I do not find them innately interesting. This is maybe a bit embarrassing as an aspiring polymath. Many of the greatest geniuses in history spoke tons of languages! But I have basically no interest in becoming a polyglot. I even tend to agree with CGP Grey’s stance that foreign languages shouldn’t be required in American public schools and universities.

But then why do I care so much about ASL? In fact, if I were to require another language in American schools, it would be ASL. At minimum, I believe it should be offered in just about every public school, whereas currently it’s a rarity. But again, why do I care? First, a bit more history.

Up through the 1950s, oralism was the dominant mode of deaf education, which forbade signing and emphasized speech and lipreading. Alexander Graham Bell is actually a bit of a bogeyman in the Deaf world, as he fought against the spread of sign language in society, albeit with the motivation of assimilating the deaf into mainstream society.

Most linguists at the time did not recognize sign as a legitimate language. Instead, it was considered a sort of pantomime, like a game of charades deaf people played. While such pantomiming can be used to communicate, it’s certainly not a language. But after a lot of work, aided by the Civil Rights Movement, this changed, and ASL was accepted as a full-fledged natural language, every bit as legitimate as spoken English.

It’s that last point that I find very interesting. Activists argued in favor of ASL on the grounds of its similarities to spoken language. On the American Sign Language Wikipedia page, I find several such comparisons:

Stokoe noted that sign language shares the important features that oral languages have as a means of communication…

…such components are analogous to the phonemes of spoken languages...

As in spoken languages, those phonological units…

Very little comparison is made to written language. In some ways, this makes sense. ASL is delivered person-to-person, and deaf people can still learn to read, while they can’t learn to hear. So in that sense, ASL is “substituting” for speaking, but not for writing.

On the other hand, speech is primarily auditory, while writing is visual. In that sense, sign is much closer to writing. Also, many deaf people can learn to speak and lipread, in which case sign is not a replacement for speaking, but rather a separate third pillar of communication. Later we’ll even see some neat features of sign unavailable in speech or writing.

Sign is closer to speech in terms of the function it serves, so when activists were striving to get it taken seriously, this comparison made sense. I know this battle still isn’t completely won, but I think it might be worth viewing sign from a different angle now. Sign really isn’t the same as speech. And I don’t mean that in a derogatory way; it’s just that sign is something more special than that.

Sign is a fundamentally different mode of communication than anything else you have learned. Learning to sign isn’t like picking up a new spoken language. It’s like spending your whole life illiterate and finally learning to read.

That is why I find it so fascinating and think everyone ought to learn it. Linguaphiles often talk of how mind-opening and mind-altering it is to learn a new language. Sign language is that times a thousand. I promise you, you can feel your brain being rewired.

Some neat features of sign language

Sign language has other things going for it, too. In terms of pure aesthetic appeal, it’s beautiful. Take this video depicting high-level ASL fluency. It might be easier to appreciate if you know some of the language, but then again, maybe not; I only want you to see how it looks. I find the sheer fluidity and expressiveness simply astounding. I think it’s such a blessing that we have these languages in our world. It would be a sadder planet without them.

Sign language is also useful. Let’s start with the basic use case: talking without making noise. This is obviously useful if you’re in a situation that demands silence, but perhaps less obviously, it helps in noisy environments, too! It can also allow you to communicate across larger distances. Communicating across a crowded room is easier in sign than in speech. When I was in 3rd grade, we used sign to ask for permission to get a drink of water or use the bathroom without interrupting the flow of instruction or mildly embarrassing ourselves in front of the class (I appreciated this so much).

More exotically, there’s the concept of signing space and placement. You can use the 3D-structure of the space in which you sign to communicate information. For example, when describing a scene, you can visually “place” objects in various locations to depict their relative locations and sizes. And this isn’t the only way to use placement. You can also introduce characters into a conversation by signing their name, and then virtually “placing” them in signing space. When you refer back to this location, you are referencing this person again.

This relates to the idea of role shifting. When recounting a dialogue, after placing the speakers in signing space, you can shift your body into a given location to indicate that you are speaking as that character. It’s a very useful and fluid way to express who was talking when, which I think outperforms simple pronoun usage in English.

It’s also been argued that babies can start learning to sign sooner than speaking, since the hands are easier to manipulate than the complex muscles of the face and throat. I haven’t been able to find thorough linguistic research on this, but I learn towards it being plausible. My wife works in daycare and preschool, and she swears it’s true! It definitely helps if children’s speech abilities are delayed.

A brighter (and cooler) future

Then there’s the accessibility argument. It would be a wonderful world if any Deaf person could walk into any establishment with the expectation that someone there will be able to sign. Many Deaf people desperately wish that all public schools taught sign language and all hearing people knew it.

On its own, this might seem like a rather large accommodation to make. But given that sign language is valuable in and of itself, I think it’s an important additional point. If we all learn this useful, mind-opening, and beautiful form of communication, we alsobring massive accessibility to a disadvantaged minority, just as an added bonus! Sweet, right?

The wonderful ASL teacher Dr. Bill Vicar’s also has an interesting tipping point model, in which he references Metcalfe’s Law: “The value of a telecommunications network is proportional to the square of the number of connected users of the system.” Extending it to sign language, he argues that the more people learn ASL, the more useful it will become. If enough people start teaching and learning it, we could hit a tipping point where it becomes quite useful for everyone to know!

When I imagine a world in which everyone signs, the main thing that thrills me is how cool that would be! (And imagine how cool in particular it would be if all rationalists learned to sign!)

Which sign language to learn?

Here’s a final thought: which sign language should you learn? I’ve focused on ASL, but many countries have their own sign language. If you’re learning sign in order to communicate with your local Deaf community, then of course you should learn your local sign language. Many local sign languages, however, are quite small and/​or unsupported. It may be difficult to find appropriate learning resources. In addition, if you’re learning sign language for its own sake, or for networking effects, you may want to learn one that’s bigger.

ASL is one of the largest sign languages in the world, and also one of the most well-developed and well-supported. Several of the larger sign languages are more splintered within their home countries and have less learning resources. In contrast, ASL is highly accessible, and while there are dialects within America, it’s still pretty unified.

In addition, ASL has constant contact with English, and has naturally developed some overlap ( many words are fingerspelled in English, for example). English is currently the most commonly spoken language in the world, with 66% of its speakers having it as a second language. It is the lingua franca. Perhaps ASL can serve a similar role, as a focal point to unite around.

  1. ^

    Basic signs spontaneously invented by deaf children who don’t have much other linguistic input.

  2. ^

    Formed when an unusually large number of deaf people are born in a relatively isolated area.