In his writings, Keisai challenges the notion that China lies in the center of the world and occupies the majority of it, leaving places like Japan on the periphery. To the contrary, he argues, there are a great many countries/lands in the world, and several of them are tens the size of China; China does not even occupy one-hundredth the land area of the world. Thus, he posits, China should not be considered "central." He further suggests that each land be considered its own separate realm (tenka, "Under Heaven"), "defined by the extent to which its customs prevail. ... none is more noble or base than any other." He suggested that just as the great Sage King Shun could not help that he was born to a perverse father, but observed filial piety nevertheless as a devoted son, so too, though Japanese cannot help being born into a society that has never produced a Sage King, they too can observe devotedly the customs of their own land, and in this manner attain moral excellence.
In defending the idea that Japan not be considered "barbarian" relative to China, Keisai points out that many parts of China were previously considered barbarian lands before being incorporated into China (kara). Some Chinese Imperial capitals, he points out, were even located in formerly barbarian lands, and great Chinese Confucian scholars such as Zhu Xi came from areas formerly considered barbarian lands. As a result, instead of the use of terms such as "civilization" (華) or "Middle Kingdom" (中国) and "barbarian" (夷), he advocates the use of the terms wagakuni (我が国, "our country") and ikoku (異国, "foreign" or "different countries") to refer to one's own land, and to other lands, respectively, without the implication of this civilized/barbarian connotation.
Keisai's thought differed importantly, too, from that of the kokugaku (nativist, or National Learning) scholars in that he did not suggest a syncretic explanation for the alignment of Confucianism and Shinto, as manifestations of a single universal Way, suggesting instead that the two corresponded by coincidence.
- Bob Tadashi Wakabayashi, Anti-Foreignism and Western Learning in Early Modern Japan, Harvard University Press (1992), 30-35.
- Ono Masako, Tomita Chinatsu, Kanna Keiko, Taguchi Megumi, "Shiryô shôkai Kishi Akimasa bunko Satsuyû kikô," Shiryôhenshûshitsu kiyô 31 (2006), 228.
- Wakabayashi, 32.