Yamazaki Ansai (born Jan. 24, 1619, Kyōto, Japan—died Oct. 16, 1682, Kyōto) was a propagator in Japan of the philosophy of the Chinese neo-Confucian philosopher Chu Hsi (1130–1200). Ansai reduced neo-Confucianism to a simple moral code, which he then blended with the native Shintō religious doctrines. This amalgamation was known as Suika Shintō.
A Buddhist monk early in life, Ansai began to study Confucianism and gradually turned against Buddhism. By the time he was 29, he had become a Confucian teacher, gathering thousands of students, among whom were some of the greatest scholars of the day.
From the complex philosophic system of Chu Hsi, Ansai extracted the simple formula “Devotion within, righteousness without.” By the former he meant the neo-Confucian emphasis on sincerity and seriousness. But in Ansai’s hands, these concepts took on religious connotations. Indeed, as Ansai grew older, he began to combine the ethical doctrines of Confucianism with the religious values of Shintō. He equated the Chinese speculations on the universe with Shintō creation legends and identified the various elements of the neo-Confucian metaphysical principles with the Shintō gods. The Supreme Ultimate (T’ai Chi) of the neo-Confucianists (i.e., the normative principle underlying the various objects and affairs of the world) became identified in Ansai’s system with the first two divinities mentioned in the Shintō religious chronicles.
His amalgamation of Confucian morality with the Shintō tradition of the divine origin of the imperial line was one of the philosophical roots of the later extreme Japanese nationalism and emperor worship. Ansai was himself intensely nationalistic: he instructed his disciples that if Confucius and his great disciple Mencius were to come to Japan at the head of an invading army, the students would be obliged to don their armour and attempt to capture both sages.