After the collapse of the shogunate, he moved to Shizuoka, where the Tokugawa family had retired, and studied medicine in a hospital there. He went to Tokyo in 1871 and studied in the Kyoritsu Gakusha school operated by Seki Shimpachi, a scholar of English. When Seki took a position in the Finance Ministry, Taguchi became a student attached to the Translation Bureau of the ministry, applying himself to the study of economics and English. He completed the course of study in 1874.
He held the degree of Doctor of Law
Until 1878 he did translation work in the Currency Bureau of the ministry.
During the period 1877-82 he published a work called Nihon kaika shoshi, a systematic history of Japanese culture that was influenced by the writings of Guizot and Buckle and stressed matters of production and the living conditions of the common people. Because of these features and the fact that it attempts to define the principles of social evolution, it has proved to be a pioneer work in its field.