Today we start our Language Learning Grand Masters series with Dr. Stephen Krashen. At the university I learned about Krashen, but it was in a very brief way, so that when I started reading Krashen by myself I suddenly realized “oh, some time ago some teacher in some class talked about this guy”. In fact, most language students at university don’t know about Krashen. But why should you know about him? First, because his ideas about language learning are, in my humble opinion, amazing! Second, because every serious language learner will greatly benefit from reading and knowing Krashen. Let’s take a quick look at what Wikipedia says about him:

Stephen Krashen is professor emeritus at the University of Southern California, moving from the linguistics department to the faculty of the School of Education in 1994. He is a linguist, educational researcher, and activist. Dr. Krashen has published more than 350 papers and books, contributing to the fields of second language acquisition (SLA), bilingual education, and reading. He is credited with introducing various influential concepts and terms in the study of second language acquisition, including the Acquisition-learning hypothesis, the Input Hypothesis, Monitor Theory, the Affective Filter, and the Natural Order Hypothesis. Most recently, Krashen promotes the use of free voluntary reading during second language acquisition, of which he says “I believe that it is the most powerful tool we have in language education, first and second.” From Wikipedia.

As you can see, Krashen has formulated a series of hypotheses on language learning: The Natural Order Hypothesis, The Acquisition/Learning Hypothesis, The Monitor Hypothesis, and The Affective Filter Hypothesis. Let’s take a look at each of them:

The Natural Order Hypothesis
“we acquire the rules of language in a predictable order”

The Acquisition/ Learning Hypothesis
“adults have two distinctive ways of developing competences in second languages [...] acquisition, that is by using language for real communication [...] learning, ‘knowing about’ language” (Krashen & Terrell 1983)

The Monitor Hypothesis
‘conscious learning [...] can only be used as a Monitor or an editor’ (Krashen & Terrell 1983)

The Input Hypothesis
“humans acquire language in only one way – by understanding messages or by receiving ‘comprehensible input’”

The Affective Filter Hypothesis
“a mental block, caused by affective factors [...] that prevents input from reaching the language acquisition device”(Krashen, 1985, p.100)

From Krashen’s Comprehension Hypothesis Model of L2 learning

At first it may seem too complicated, but, in fact, the hypotheses are very simple. Acquisition and learning are different. We acquire language in natural contexts, reading, listening, talking to people. It’s using the language in the real world for real communication. On the other hand, learning is what usually takes place inside the classroom, it relates to every conscious study on and about the language. Nomenclatures, explicit grammar rules, drills, and so forth. We acquire language through input, i.e., listening and reading real content. We learn the language deliberately studying, be it in a classroom or by self-study. Although one can learn a foreign language through only input/natural learning or through only conscious learning, the best learner would be one able to balance natural acquisition and explicit learning. In other words, we need lots of input in order to acquire language, and by studying, we consciously learn the language in order to polish the few errors that the input by itself couldn’t correct.

This article is just a short introduction to Krashen. His theories about language learning goes much further. You can read his papers for free at http://www.sdkrashen.com/. Great language learners like Stu Jay Raj, Steve Kaufmann and Khatzumoto were highly influenced by Krashen, so I strongly recommend reading Krashen papers and books.