In this study, we explored the complementarity of ignorance in the study of learning as a social act and as subject matter in Japanese language education. We explored the influences of "another reader" that reads the text and "another text" that the class has been read, and the resultant ways of reading. We adopted a "Vygotsky Space" as a lens of learning and explained the relation of "another reader" and "another text" through an analysis of learners' protocols in a study of "Takasebune" at an experimental Japanese class. It was found that learners needed peers to appropriate new cognitive tools, and when a learner transformed the cognitive tools into a new usage, they needed peers to talk about the new interpretation. In the "Takasebune" class, where learners compared two scenes chosen arbitrarily, we identified possibilities of new tool use and creating new interpretations. In addition, we identified the significant meanings of the teacher's behavior that influenced learners' study and that encouraged their "Appropriation".
