The author is undoubtedly erudite and knowledgeable. He is also familiar with the works done by his Japanese colleagues. His suggestion is interesting that Chinese historians should make the studies of "the eastern ocean" as a field like the Inner Asian studies (Ch. Xiyu xue), focusing on China, Korea and Japan. However, his conclusion does not point out a new direction for us. There have been many good researches which have done by other scholars (especially anthropologists and historians who were influenced by theories of historical anthropology) following this way before the author put forward that. For example, in Taiwan, to view the Han people from border ethnic minorities was an old idea raised around twenty years ago. The author adds the perspectives from Japan and Korea. But their main concern was very similar: to observe China from her neighboring peoples.