Part I – Acquisition-Learning Distinction Hypothesis

(For an explanation of this series on the second language acquisition theories of Stephen Krashen, see this post. Also, I went straight to the horse’s mouth and got the information from “Principles and Practice in Second Language Acquisition,” which is freely available on Krashen’s website.)

Krashen’s Acquisition-Learning Distinction hypothesis, his first and perhaps most important hypothesis, claims that adults pick up languages via two distinct processes:

  • Acquisition – A subconscious process by which we are exposed to language input and then intuitively pick up its patterns. In turn, we are able both to understand and speak language without having to reason through every word and sentence construction. We’re basically on auto-pilot.
  • Learning – A conscious process by which we are taught grammar, rules, and meta-information of the language, and are expected to understand the language logically.

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What’s important to notice here is that these are treated as two completely distinct processes. In a sense, these two processes are competing for our attention. And Krashen has determined that one is much, much more valuable than the other.

I won’t make you wait for the thrilling conclusion: the winner is acquisition. Basically, according to Krashen’s writings, when you learn, you know about a language. When you acquire, you know a language.


If this hypothesis is true, it would mean a few things.

First, language learning takes time. Acquisition is a slower process than learning. Also, since it’s a subconscious activity, it’s difficult to rush, being out of our control and all.

Second, formal studying has limited impact. Studying grammar tables and memorizing vocab lists won’t tap into that acquisition process, since those activities are firmly in the domain of the learning process.

Third, we’re teaching languages wrong. Every foreign language class in every high school and college across the world “teaches” the language. They may vary slightly in their methods, sure, but at the end of the day you’re going to be doing some kind of verb conjugation or vocab memorization.

Fourth, the burden of picking up a language isn’t on the teacher, and it’s not really on the student either. It’s on the student’s brain. If acquisition is really a subconscious process, then you basically have to get out of the way and let the brain do its work and form its neural pathways. Then after enough time you know another language.

So how do we “acquire” a language? According to Krashen, it’s via comprehensible input, which is a separate hypothesis and the topic of another post.

My Take

Here’s what I think.

I think this hypothesis is definitely on to something. It would explain quite a few things:

  • Why we learn languages as children without ever picking up a grammar book or ever being “taught” a language. We’re not perfect by the time we enter school, but most of us are able to communicate fluently. And in cases where people don’t go to school and don’t receive an education, they’re still able to speak their native language enough to communicate with their neighbors.
  • Why my American colleagues in Germany–IT engineers who were educated, were extremely smart, and could pass any certification test you threw at them–had difficulty learning German, while their kids were picking it up in kindergarten. And it’s not because kids learn languages faster, because they absolutely don’t (and in fact learn slower). It’s that my colleagues were trying to learn the language and not doing the things to help them acquire it.
  • Why language learning takes time. It can take months and even years to become fluent in a foreign language. Acquisition would help explain the mechanisms behind this.

I also have a couple reservations about this hypothesis.

I’m not entirely convinced that acquisition and learning are two completely different processes. In fact, I think that a little learning can help acquisition. For example, “I have” in Spanish is tengo, while “you have” is tienes. Both are from the infinitive verb tener, which means “to have.” If you pick up that pattern on your own and acquire it, awesome. But let’s say that you “learn” that pattern, from a teacher who explains it to you explicitly. I don’t think you’re forever doomed to knowing it only superficially. It’s just that you’ve now learned it at the conscious level and need time to let it sink in subconsciously.

Here’s an example: multiplication. My elementary school teachers first taught me multiplication using things like crayons. Three crayons, three times totaled up to nine crayons. I understood the idea very consciously but couldn’t pass any math tests with that. But the next step was drills. Then multiplication tables. Then flash cards. And then years of homework. Now I have acquired single-digit multiplication. I know it subconsciously. I know that 9 X 9 is 81 without having to think about it. My learning the theory early on didn’t hinder me from learning, but actually helped me spot the pattern so that later on I could acquire it faster.

So where are we getting this disconnect? How can Krashen’s hypothesis seem so right and at the same time leave me with reservations?

Well, I have a hunch (and it’s really nothing more than a hunch).

I think that what Krashen calls “acquired” and “learned” language knowledge is labelled differently by other people. Cognitive researchers and neuroscientists separate knowledge into two kinds:

  • Declarative knowledge – Factual information, which the brain stores as static information.
  • Procedural knowledge – Knowledge of how to perform, which the brain stores as dynamic information.

With declarative knowledge, you know the names for the different parts of a bike. With procedural knowledge, you know how to ride a bike.

I think what Krashen might be referring to as acquisition is the development of procedural knowledge, while learning is the development of declarative knowledge.

If that’s the case, then it’s not fair then to lump all grammar and language instruction into the “learning” camp. Skills are successfully “taught” and “learned” all the time, at dance studios, martial arts schools, driving schools, and on and on and on.

“The Dance Class” – Edgar Degas

It’s just that with language, you have to be careful to teach the procedural knowledge and not just the declarative knowledge.

So if you’re “learning” grammar, minimize the lectures and spend more time with flashcard and workbook drills.

Wrapping Up

Let’s step back out of the textbooks for a minute and discuss the takeaways for real-life language learning.

No matter what kind of terminology you want to use–acquisition, learning, declarative knowledge, procedural knowledge, whatever–if you want to speak and understand a new language, you have to let it sink in deep. You have to let its thousands of moving parts get down deep inside you and take root so that you can understand what the other person’s saying, and then reply back instinctively, paying attention to what you’re trying to say and not how you’re saying it.

  • Pingback: Series Introduction: Stephen Krashen’s Theory of Second Language Acquisition ← Language Surfer

  • Pingback: Part II – The Natural Order Hypothesis ← Language Surfer

  • Pingback: Part III – The Input Hypothesis ← Language Surfer

  • Pingback: Part IV – The Monitor Hypothesis ← Language Surfer

  • Barbara Eckard

    I think that your assessment of Krashen’s theory is basically right. I would like to say, however, that the comment about 2 types of knowledge- declarative and procedural could be linked to acquisition and learning, but the fact that it’s neuroscientist’s and cognitive researchers using this dialogue doesn’t mean that Krashen’s assessment of it is incorrect. As an educator I would describe the phenomenon like Krashen but someone in a different field of study would use different terminology to describe the same process. The terminology isn’t what is important, it’s the process. As a language learner of languages other than English, I lived with 2 different families in Costa Rica that spoke nothing but Spanish. As a result I “picked up” more of the language faster than just studying the grammar, phonetics and phonology of Spanish. I realize the two processes worked together to build fluency more rapidly but it was due to the comprehensible input I was hearing that made me want to learn the language faster so I could communicate with those around me.

    • Ron G.

      Hi Barbara, thanks for stopping by and commenting! I probably didn’t clarify correctly what I was thinking. This is admittedly heavy stuff. :)

      But what I was trying to get across was that grammar instruction can consist of both (a) labeling the language’s structure and (b) practicing actually using the language’s structure–i.e., drilling. In his writings, Krashen seemed to focus mostly on (a) whenever he referred to “learning” or grammar instruction.

      It seemed to me that Krashen didn’t find (a) at all useful, and I tend to agree with him on that. But I think (b) can be useful. It’s not so much that I think he’s wrong with his labels; it’s that I think he completely overlooked one kind of grammar instruction, the kind that is in fact most common in language classes.

      Your story is fascinating, by the way. How long were you in Costa Rica? After really digging into Krashen’s theories, I’ve been ramping up my comprehensible input and I have to admit that it’s making the language come together more than ever for me.

      • Barbara Eckard

        Ron, Thanks for clarifying your statements and I do agree with what you said. I was in Costa Rica for eight months from April-December 1981. It was part of my training to become a literacy specialist with Wycliffe Bible Translators in Guatemala.
        I’m glad to hear that the comprehensible input is working well for you. It certainly helps develop more neurotransmittor passageways in the brain if you are using input that you encounter on a regular basis.

    • Ron G.

      Whoops, just saw your other comment. :)