He suggested and implemented the following policies: the Charter Oath of Five Articles, the nurturing and promotion of mass media, the abolition of feudal conventions, the reversion of people and lands to the emperor, the abolition of the feudal domains and the establishment of prefectures, meritocracy, equality of the four classes, the establishment of a constitution, the separation of the three powers of the state, the introduction of the bicameral parliamentary system, the advancement of education, and the establishment of legalism.
五箇条の御誓文、マスコミの発達推進、封建的風習の廃止、版籍奉還・廃藩置県、人材優先主義、四民平等、憲法制定と三権分立の確立、二院制の確立、教育の充実、法治主義の確立などを提言し、明治政府に実施させた。