[1] Its achievements included publishing Kaizō, a popular general interest magazine which carried both works of fiction and articles pertaining to social issues and socialist thought.

[1] He began by launching the general interest magazine, Kaizō (改造; English, "Reconstruction"), which during the 1920s would become a forum for Marxist and socialist debate.

The magazine also published articles by foreign intellectuals such as Bertrand Russell and Albert Einstein, with the result that it became a voice in Japan of "new trends in thought and science".

[2] Yamamoto also invited Russell, Einstein and other prominent foreign personalities, including Margaret Sanger (March 1922)[4] [5][6] and George Bernard Shaw (February 1933),[7] to visit Japan.

Before and after his visit Russell contributed fifteen essays to Kaizō, which were published in English-Japanese bilingual editions and all "discussed social and political problems, except one on the Theory of Relativity".

[14] World War II saw increases in political repression, with events such as the Yokohama incident, in which three dozen intellectuals (including editors of Kaizō) were arrested.