Why learn a foreign language?


The last post, "Don't TEACH a foreign language…" [implied follow-up: teach IN one!] garnered some good questions from smart people. (Thank you, smart people, for reading this blog!) Answers are owed!

Why learn a foreign language?

That a school ought to teach a foreign language will seem, I suspect, self-evident to many of you. I'm embarrassed to say that it wasn't obvious to me, for reasons I still find difficult to fathom.

Maybe I held back from wanting to include a foreign language because I had never seen it done well. I'm the product of foolishly designed language learning: I tried and failed to learn Greek (1 semester), German (2 semesters), and Hebrew (4 semesters). I got 'A's and 'B's in all of the classes. I just couldn't do much of anything with the languages at the end.

Note, too, that my actual instructors were top-notch! The problem wasn't the teachers, it was when and how I was learning. My language learning had departed from the guaranteed-to-work natural method of immersion when young.

I didn't want to inflict this on our students. And now [chuckle] I do, because we can build a system — teaching young kids in a foreign language — that seems likely to work!

But: so what if it does work? Why learn a foreign language?

More human humans

One crucial purpose of our school is to expand people's horizons. Whatever specific geography, socioeconomic class, ethnic heritage, and culture children are born into, there's much to drink from — but it's crucial that children not be confined there. 

I am, and in some ways am always bound to be, a white middle-class Midwesterner. I have no particular problems with that. But I'm not forever stuck only seeing the world through those lenses. I can take on other perspectives. I can expand myself.

But one of the greatest blinders is language. If you can't understand another people's language, you're limited to understanding them in translation (which is forever lossy) and by recourse to texts that have been translated (which are rarer than stories that are not).

I was born into a linguistic community — English — and I've found it quite difficult to move beyond that (see my failed attempts above). This is (and will likely remain) a huge limitation of mine.

If we can succeed at helping entire schools of kids speak and read another language, we can give them a bridge into another linguistic community. They can read non-American newspapers! They can banter on online forums! They can have a bit easier time seeing the world from the eyes of people unlike them, and joining in the conversations that those others are having.

Again, one of the ideas I'm trying to squeeze inside "a school for humans" is the idea that we can help kids become more fully human by connecting them to the rest of human experience.

Learning a second (or third) language is one piece of that.

And if that were the only benefit kids received from learning a foreign language, it'd be enough. But, it turns out, that's not the only benefit.

Improved executive functioning

I think we've all, by this point, heard that learning a language is good for your brain. It's worth delving into how.

Speaking multiple languages doesn't improve many aspects of cognition: it doesn't help long-term memory, doesn't help retrieval speed, doesn't help mood regulation. What speaking a second (or third…) language does help is one crucial cognitive tool: executive functioning.

Executive functioning is a big deal — in many educational psychologists' minds, it's one of the biggest. Executive functioning is what gives you the ability to regulate your thinking. It's one of the elements that distinguishes you the Homo sapiens from you the Australopithecus. Executive functioning is bound up in self-control, concentration, deliberation, mindfulness, working memory, and — goodness gracious — even IQ!

Speaking multiple languages does not improve all of executive functioning. But it is demonstrated to improve one crucial aspect of it: the ability to keep up when rules change, and when information is misleading.

An example is in order! This example comes from Jared Diamond's The World Until Yesterday: What Can We Learn from Traditional Societies? The book is, frankly, a must-read: more useful, I think, than either his Guns, Germs, and Steel or Collapse. Throughout the book Diamond is consumed with demonstrating how the practices of traditional ("hunter-gatherer" as well as early agricultural) societies can inform how we might create a flourishing society. It's a benefit of the book that he does so quite evenhandedly: he neither sentimentalizes nor demeans as "primitive" the practices of traditional societies. In chapter ten, he demonstrates how multilingualism is our heritage, and how monolingualism can hold us back. And he describes the following experiment:

Children sit in front of a computer. Shapes appear on the screen, and the children are instructed to press a specific button when certain shapes come up. Sometimes the shape is a red square, which appears on the left of the screen; sometimes it's a blue square, which appears on the right of the screen.

The keyboard has two buttons: a red button and a blue button. The instructions are simple: when the red square comes up, press the red button, and when the blue square comes up, press the blue button.

Take a moment to picture that.

In one version of the experiment, the location of the buttons matches the location of the shapes: the red button is on the left side; the blue button is on the right side. In this version, monolingual students do just as well as multilingual students.

But in the other version of the experiment, the buttons are swapped: the red button is on the right, and the blue is on the left. There's a mis-match, and it's easy to get confused. "Wait," I can imagine myself asking, "am I supposed to press the button that matches the color of the square, or the location?" In this version, there's irrelevant information that the student has to disregard. They have to exercise their executive functioning.

And in this version, the monolingual students are helpless. They can't keep up with the multilingual students.


Jared Diamond gives a good hypothesis. When I (as a monolingual) hear the word "burro", what goes on in my brain is pretty simple: the word triggers an item in my long-term memory (a donkey). No executive functioning is necessary — the meaning is recalled automatically.

But the sound BUH-ro means other things in different languages. In Italian, for example, it means 'butter'. If I spoke both Italian and English (or, for that matter, Italian and Spanish) and heard the sound BUH-ro, I couldn't automatically link the word to its meaning: I'd need to first check the context. "Hold up — am I listening to English, or to Italian?" Only then could I understand whether you were asking me to, say, pass you the butter for your toast, or hoist a large hoofed mammal across the table.

Which is all to say: knowing multiple languages makes listening harder. It means that you have to consciously be suppressing certain meanings, and channeling others. And in this difficulty is great cognitive training.

But where does this get us? Again: acquiring a second language doesn't improve thinking as a whole, just one aspect of executive functioning: the ability to keep up when rules change, and when information is misleading.

Who cares about that? Well, you probably do. Two explanations are in order.

Bilingualism and Alzheimer's

First, we know that thinking is a use-it-or-lose-it proposition. We tell dementia patients to play bridge, or solve Sudoku puzzles, and for good reason. But, as Diamond points out, "whereas even a bridge or Sudoku fanatic can play bridge or solve Sudoku puzzles for only a fraction of a day, bilingual people impose extra exercise on their brain every second of their waking hours" (p. 394).

Maybe the greatest evidence of the cognitive benefits of bilingualism, in fact, come from the world of Alzheimer's. We've long known that education level is one of the best predictors of Alzheimer's: those with more education get the disease less. (It's thought — though not quite proven — that this is because people who enjoy thinking tend to stick around longer in formal education.)

A 400-person study in Toronto (I'm pulling this study from Diamond, again) followed folks with a probable diagnosis of Alzheimer's. Bilingual patients ended up developing the disease 4-5 years later than did monolingual patients. Since people tend to get Alzheimer's in the last years of their lives, this means that nearly half the people would not get Alzheimer's before they died. And this was true despite two nearly incredible facts: first, the bilingual patients in the study had less education on average than the monolinguals. Speaking a second language trumped education. Second, that when autopsies were done, it was discovered that the bilingual patients had on average more brain atrophy. Speaking a second language maintains cognitive functioning even when one's brain is shrinking.

Alzheimer's runs in my family: this floored me. But I bring up these findings not for what they say about dementia as much as what they imply about cognitive functioning in general.

Bilingualism and life in a topsy-turvy world

To repeat to the point of inanity: knowing a second language improves one's ability to keep up when rules change, and when information is misleading.

If that describes the 21st century to you — well, we're in agreement! Technological innovation is speeding up — we're creating new things faster than we ever have before. We live in a giant jumble. The rules are constantly changing.

I sometimes hear educators conclude from this that schools should abandon teaching everything they've taught before: we should evacuate our ship of content and embrace constant curricular innovation.

I think that's a dangerous idea, for reasons that I'll post about in the future. But I want to say now that these educators are correct in an important sense: because we live in an information jumble, we do need to re-invent schooling.

Helping improve students' executive functioning seems to be one important piece of that. We want to ground students in the deeply human ideas of the past and present, but we also want to make it easier for them to change course in the future.

That's a brief for why we need to help students keep up when rules change. What about the second half — helping students keep up when information is misleading?

Information is always misleading.

Nassim Nicholas Taleb aphorizes, in his book The Bed of Procrustes:

They think that intelligence is about noticing things that are relevant (detecting patterns); in a complex world, intelligence consists in ignoring things that are irrelevant (avoiding false patterns).

Our problem typically isn't that we're not paying attention, it's that we're paying attention to the wrong things. And — apparently — knowing a second language can increase our fundamental ability to fix that.

Multilingualism is good for the mind. And, as a school that takes mental development of all sorts very seriously, bilingualism seems like something we can't afford to pass up.

A note: Mark asked, in his wonderfully-rich comment on the last post, whether the cognitive benefits of a second language accrue only when one learns it "unnaturally," after the critical period closes in adolescence. Happily, the answer from my research seems to be no. All the above studies, for example, were done with people who had learned their second language in childhood. In fact, some of the studies on the benefits of executive functioning and accelerated learning come from infants, who are only able to listen to the languages! If you're interested in more, grab a copy of The World Until Yesterday.

If anyone knows any evidence to the contrary — evidence that the cognitive benefits of second-language-learning come only when learning the language after adolescence — please let me know! (It seems entirely possible that learning a language at different times offers different benefits.)

I'll respond to more comments and questions on Wednesday — keep 'em coming, readers!