In 1927 he graduated from Keio University with the thesis entitled Nikon shihon shugi hattatsu ski (“History of the Growth of Japanese Capitalism”), and its contents were introduced in Shakai mondai kenkyu (published by Shinchosha) and other publications.
In 1929 he played a leading role in the founding of the Proletarian Science Research Center. In 1930 his graduation thesis was published in book form, and the same year he became a member of the Japan Communist Party. In 1931 he participated in the planning and editing of a series of lectures on the history of the growth of Japanese capitalism prepared by a number of scholars. He thus became a leading spokesman for the theories of the so- called lecture group, w'hich was soon engaged in a spirited controversy with the members of the “labor-farm group.”
From the autumn of 1932 on, he was engaged in various illegal underground activities. As a member of the secretariat of the Central Committee of the Japan Communist Party, he worked in cooperation with Miyamoto Kenji and others to rebuild the party and, in spite of the fact that he was suffering from chest disease, continued to edit the lecture series for publication by Iwanami Shoten. In 1934 he was arrested and subjected to torture at the Shinagawa police headquarters and died thereafter in Shinagawa Hospital.
While still a student in the economics department of Keio University, he joined Nosaka Sanzo in doing w’ork for the Industry and Labor Research Center and was active in the Mita Social Science Studies Society and the labor school affiliated with the Japan Federation of Labor.
In 1926 he was implicated in the investigation of left-wung student activities in Kyoto and charges were brought against him.
In 1930 he became a member of the Japan Communist Party.