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The Compelling (not just interesting) Hypothesis
Stephen Krashen
The English Connection (KOTESOL) in press

It is by now well-established that input must be comprehensible to have an effect on
language acquisition and literacy development. To make sure that language acquirers pay
attention to the input, it should be interesting. But interest may be not enough for optimal
language acquisition. It may be the case that input needs to be not just interesting but
compelling.
Compelling means that the input is so interesting you forget that it is in another language.
It means you are in a state of "flow" (Csikszentmihalyi, 1990). In flow, the concerns of
everyday life and even the sense of self disappear - our sense of time is altered and
nothing but the activity itself seems to matter. Flow occurs during reading when readers
are "lost in the book" (Nell, 1988) or in the "Reading Zone" (Atwell, 2007).
Compelling input appears to eliminate the need for motivation, a conscious desire to
improve. When you get compelling input, you acquire whether you are interested in
improving or not.
The evidence for the Compelling Input Hypothesis includes improvement as an
unexpected result, the many cases of those who had no conscious intention of improving
in another language or increasing their literacy, but simply got very interested in reading.
In fact, they were sometimes surprised that they had improved.
I included several cases like this in The Power of Reading (Krashen, 2004, pp. 22-24):
Both students and teachers were surprised by the students' startling improvement in
English after they became avid readers in English.
More recently, Lao (Lao and Krashen, 2009) described the case of Daniel, a 12-year-old
boy who came to the US at age eight from China. Daniel's Mandarin proficiency was
clearly declining, despite his parents' efforts: They sent Daniel to a Chinese heritage
language school but it was clear that Daniel was not interested in Mandarin. He was also
not an enthusiastic participant in a summer heritage language program supervised by Dr.
Lao, even though it included free reading.
Then Dr. Lao gave Daniel a few books written in Chinese to take home. One was an
illustrated chapter book, "The Stories of A Fan Ti." Daniel loved it. The book was a bit
beyond his level, but thanks to the illustrations and his ability to understand some of the
text, Daniel was very interested in the story, and begged his mother to read it to him.
When Dr. Lao learned of this, she loaned Daniel more books from the "A Fan Ti" series,
in comic book format. Daniel begged his mother to read more, from two to five stories
everyday. Daniel liked the books so much that he would do the dishes while his mother
read to him. Both Daniel and his mother were quite happy with this arrangement. Daniel's
Mandarin was clearly improving, but he wasn't aware of it, nor was he particularly
interested. He was only interested in the stories.
The Compelling Input Hypothesis also explains why self-selected reading is typically
more effective than assigned reading (e.g. S.Y. Lee, 2007).
An important conjecture is that listening to or reading compelling stories, watching
compelling movies and having conversations with truly fascinating people is not simply
another route, another option. It is possible that compelling input is not just optimal: It
may be only way we truly acquire language.
References
Atwell, Nancy. 2007. The Reading Zone. New York: Scholastic.
Csikszentmihalyi , M. 1990. Flow: The psychology of optimal experience. New York:
Harper Perennial.
Krashen, S. 2004. The Power of Reading. Second edition. Portsmouth: Heinemann and
Westport: Libraries Unlimited
Lao, C. and Krashen, S. 2008. Heritage language development: Exhortation or good
stories? International Journal of Foreign Language Teaching 4 (2): 17-18.
Lee, S. Y. 2007. Revelations from Three Consecutive Studies on Extensive Reading.
Regional Language Center (RELC) Journal , 38 (2), 150-170.
Nell, V. 1988. Lost in a Book. New Haven, Conn.: Yale University Press.