The aim of this paper is to explicate the characteristics and problems of the theory of "Logic and Rhetoric of Writers" by T. Saigo, the chairperson of Bungei-Ken. He asserts that we don't have to take much time in teaching expository texts, because good texts can be understood at a first reading, and the most important object of teaching expository text is to help pupils and students to learn "Logic and Rhetoric of Writers". The assertion results from examining of defective practices in the teaching reading comprehension in which the contents of the texts have been regarded as very important and been paid no attention to the characteristics of methods of cognition and expression. Saigo has developed a tentative curriculum from elementary school to secondary school for cultivating the abilities of cognition and expression, and has been improving it through practicing. The curriculum is of great value, because perhaps, it is the first trial to systematize the abilities of recognition and expression as a curriculum of Japanese language teaching, including expository text teaching as an important part of it. A problem to be examined is that it carn be built as a spiral curriculum or not.