#003 – The Input Hypothesis – Dr Stephen Krashen

September 27, 2018 - By 

#003 – The Input Hypothesis – Dr Stephen Krashen

00:00 / 1:00:27

Dr. Stephen Krashen  is linguist behind the Input Hypothesis, which revolutionised our understanding of the way languages are learned. If you want to speak a foreign language well then you must become familiar with him and the hypothesis.

In this Episode of the podcast we discussed: 

  • Dr Krashen’s research which reveals that conscious knowledge of language is not the key to language acquisition.
  • Why reading and listening are key ingredients in language acquisition (Fluency Activator 6 & 7)
  • How to get comprehensible input.
  • Why it’s important to enjoy the content you read and listen to in a foreign language.
  • Why most people fail to learn a foreign language.
  • The best type of people to help you improve your comprehension and speaking skills.

Episode Transcript

David: Today I’m speaking with Stephen Krashen, Dr. Stephen Krashen, a renowned linguist in the second language acquisition space and I’m really excited to speak with him today because I’ve read many of his journal articles and I’ve read some of your books as well. And I’m excited to dive deep into what we call the “Input Hypothesis” because this is also something that revolutionized the way that I learn languages. I actually studied it at university as well. So to get to speak with you today is an honor. I could keep talking forever but I think that you would do a better job of introducing yourself so could you please first introduce yourself and tell us a little bit about your history as a linguist and some of the work that you’ve done.

Dr. Stephen Krashen: Okay, it’s interesting that I’m described as a linguist. That’s actually technically correct because my degrees are all in linguistics, except my undergraduate degree, which is in music—which is another story. I describe myself as a recovering linguist. I have a Ph.D in Theoretical Linguistics, where I studied with great enthusiasm everything written by Noam Chomsky but my theories and my research all says that conscious knowledge of language is not the key to language acquisition so it goes against everything that I did before. In the old days, we did something called applied linguistics. Applied linguistics means study all the rules, learn the grammar of language, and then apply them to pedagogue. No more. What we now do is language acquisition. And in 1975, when I was already in the field working as an assistant professor in New York, the idea came to me that we don’t acquire language by studying it, we don’t acquire language by conjugating verbs, memorizing lists of vocabulary words, we don’t even acquire language by speaking or writing. We acquire language by listening, by reading, by understanding what people tell us, and understanding what we read. The message. In fact, in the last few years, I’ve become more and more interested in the idea that we acquire language when we’re deeply listening to the message. When we’re not even thinking about whether it’s in another language. When we’re so interested in what we’re reading or listening to that we have no idea it’s in another language, we have no idea what grammatical constructions are used when the input is totally compelling. This all started in the 1970’s, when I was interested in adult second language acquisition because that’s what I was doing. I was the director of an ESL program, English as a Second Language program in New York and we had these adult students. And the original work showed that adults do better when they get comprehensible input, interesting messages. After that, it spread, I discovered to my great delight, that it worked for child second language acquisition too. And then after that, in the 1980’s, it occurred to me that this worked for first language development and then it worked for literacy development. I was influenced in 1985, I think it was, when I read a book called Reading Without Nonsense by Frank Smith. And I found my theory there, I found all my ideas there, written years before I had thought of them from a completely different source of different data and expressed much more clearly than I ever had. Smith had it all worked out, it was beautiful. And that pushed me ahead 10 years. And I should put in a commercial message, I’m still very dependent on Frank Smith, who along with my son, I think is one of the most brilliant people on the planet. He and Kenneth Goodman had this idea that you learn to read by reading. You learn to read by understanding what’s on the page. After that I discovered that the idea of comprehensible input, we acquire language by understanding helped explain bilingual education. Why some bilingual programs were more efficient than others. The good ones gave you background information that made input more comprehensible. About 10 years after that, I got interested in animal language. And I’ve been looking at the research on parrots, on songbirds, on chimpanzees, and guess what, the comprehension hypothesis has something to say about this too. And I actually wrote a paper which people can find on my website, sdkrashen.com, called Cosmo, a parrot that I have actually interviewed and met, along with my grandchildren, in Athens, Georgia, who speaks English pretty well, no kidding.


And comprehensible input gives a very interesting insight into Cosmo. It works not perfectly, but pretty well.

David: Okay. So, for those of you listening, I want to just give a quick summary of what you’ve said here. So the input hypothesis, just to make it clear, is a theory that says that we learn to read by reading, we learn to listen by listening, and what we need to acquire language is called comprehensible input. Comprehensible input is self-explanatory and it’s when we are able to understand the messages that are being communicated to us. Correct? So could you tell us a little bit about how you discovered this hypothesis or how you discovered this theory that we acquire language in this way? What steps did you go through and what was your epiphany moment, if there was one?

Dr. Stephen Krashen: Yes, there were several epiphanies. What happened was, in the 1970’s, 1975, I was teaching in New York and I had a problem. There was data I couldn’t make sense of. Two different kinds of studies. One was studies that we found of adult second language acquirers have the same order of acquisition as child second language acquirers. This was based on the work of Heidi Dulay and Marina Burt, who had done work in second language in children. And we, my colleagues and I, looked at adults and found very similar patterns, which were very interesting. Carolyn Madden, F. Lee Bailey, and I published several papers on this in the 70’s. The order of acquisition was similar to the difficulty order. What they found easy and what they found hard. But we also found that it only appeared if you gave them a real communicative situation where they weren’t thinking about grammar and they were just communicating. If you had them write and focus on correctness, or gave them a grammar test, the order changed. Most writing stayed the same but if it’s a writing with “make sure this is correct,” then it changed. Things like the third-person singular, which is usually late acquired, jumped up in the order example, it was more accurate. Another study at the same time, based on a student of mine named Pauline Ponn. Let me tell you about Pauline. She took several of my classes, one at Queens College, one at the graduate center. At the time she was in her 40’s and she was an immigrant from China, first language Mandarin. Her written English was phenomenal. She wrote some of the best papers I had ever gotten from a student still, both in form and content. And it was very accurate and well stated. Her spoken English, she had an accent, she occasionally made mistakes. The term paper that we decided on, that she decided to do, was based on herself. Her son was 16, native speaker of English, native level and in their apartment in New York, they left slips of paper around. And every time she made a spoken mistake, her son wrote it down. At the end of semester, we looked at the mistakes. She could self-correct nearly every one. Those two studies combined, those two problems, this was in the epiphany. There was the only way out was to hypothesize that there are two systems going on. There’s a consciously learned grammatical system and there’s a subconscious system naturally acquired, which is similar to what children have. And if you peel away the conscious mind in adults, you see the child subconscious natural mind—I thought that was a very beautiful idea. So what happened to Pauline, when she wrote, she appealed to this conscious grammar. But when she just spoke to her son, she didn’t worry about it, she used her subconscious only. Similarly, in the natural order studies, when people are just talking they use the subconscious system. But then when there’s a grammar test, they superimposed on it this grammatical system, which I hypothesized was used as a conscious monitor. That was the first breakthrough and it was a secondary analysis of older data that did it. It was trying to make sense of old research, which is, as we know in history of science, the way Albert Einstein came up with the theory of relativity based on research done 30 years ago, Maxwell’s research, etc. So this, generally, I found out later what happens in science. The other epiphany happened in a class I was auditing, taught by my colleague Eleanor Oaks, and I was listening to what she said and suddenly it hit me, “My gosh, this is how language is acquired.”


I don’t know what she said but it started me thinking and I tuned out for the next 10 minutes and I started scribbling. And it seemed to me too simple. We acquire language when we hear it and read it and there are aspects of grammar that we haven’t yet acquired. And it seemed to me this was too simple to be true and maybe everybody knew all about it. So I turned to one of my students next to me—I wrote this out, I didn’t disturb the class—Tina Bennet and I said, “Is this how it happens?” She wrote back, “Yeah, probably. No, we didn’t know about it. This is new.” Finally, the third epiphany was happening when I was on the freeway on my way to Riverside, California and it hit me that optimal input, if you give people a lot of comprehensible input, all the grammar rules that people are ready to acquire is already there in the input. We don’t have to teach along the natural order. Just like the balanced diet will give you all the calcium you need, all the iron I need, all the vitamin B-25 that somebody else needs, etc. Not only that, it has all the vitamins that have yet to be discovered, that scientists don’t know about, and they’re recycled in just the right amount, etc. So, those are the three individual breakthroughs that led to the theory. And the fourth one, which was a year-and-a-half ago, is based on the work of my former student Christy Lao, who had a student in her summer class— she teaches a summer Mandarin class, special seminars in Richmond—she had one student who spoke Mandarin as a first language but his English had totally outstripped his Mandarin, which we find in immigrants, and he wanted to drop the class. She gave him a book, said, “You can drop the class but let me give you something to read, you might like it. Here’s a going away present.” It was the stories of Afanti, the graphic novel written in Mandarin, which is popular in Chinese-related language speakers all over the world. He absolutely loved it. It was a little hard for him so he asked his mom to read the stories to him. And she got more of them from Christy. They were so wonderful that he wanted mom to read these stories all day, three or four a day. Finally, he and his mom made a deal, she would read him the stories while he did the dished. It worked out for everybody. This is a 9-year-old kid. His Mandarin got better, and better, and better. At no time did he care about Mandarin. He cared about the stories. This young man, Jack, knew something that we in language education don’t know. Most people don’t care about acquiring languages. Most people care about getting through the day. If they’re kids, they care about going to th

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