Current dabete on reforming graduate education in Japan, which emphasizes the excellencies of American graduate schools and tries to introduce their system into Japan, mostly neglects the examination of actual training process. Structural features of American graduate programs appear to be similar. The requirements and their sequenses to doctoral degrees at various institutions, for example, show rather same patterns. The coursework at the first one or two year(s), is followed by the some kind of comprehensive/preliminary examinations and finally working on the dissertation. But the content of coursework and the way to administer the examinations differ from one discipline to another and even in the same discipline from one department to another. Especially one of significant aspects of the homogeneity-heterogeneity argument is as to the similarity of the curriculum in one discipline, since the existence of similarity of the curriculum means the consensus on what constitutes of the "core" of one discipline as well as the integrity of it. American Sociological Association and many concerned sociologists have been examined this problem since 60s. They conclude that "Theory", "Research Methods" and "Statistics" have been the "core" of graduate curriculum in the education of sociologists, based on the analysis of courses listed in Guide to Gradaute Department of Sociology since then. Some argue, however, that sociology is divided into two theoretical camps, positivistic and interpretive, in addition to the division between qualitative methodologists and quantitativeones. Therefore to determine the exact "core" of sociology curriculum reqires the carefull examination of course syllabi of each department. By doing this we can also determine whose and what writing is considered as "canon" in sociological knowledge today.