Abstract:During the Edo period, Ishida Baigan, the founder of “Sekimon Shingaku”, advocated the syncretism of Shinto, Confucianism, and Buddhism to educate the general populace. He believed the loyalty ethics of Confucianism, the mercy ethics of Buddhism, and the integrity ethics of theology share the common essence. They are all essential to the cultivation of mind. Based on the union of the three religions, he advocated the practice of “integrity” and “frugality” to seek “conscience”, from which he developed “Business Ethics” for modern Japanese businessmen, and then developed it into “Sekimon Shingaku”. His ideas spread first among business people and then among the majority of peasants and warriors. It is generally agreed by academics that Ishida Baigan’s thought has profound influence on the development of modern Japan’s intellectual, economic, and educational history.