sentences:  In 1953, he became a full professor at Tokyo Metropolitan University, a post he eventually resigned from in protest at the abuses of parliamentary voting procedures during the period of civil unrest and protest that arose while the ratification of the revised Treaty of Mutual Cooperation and Security between the United States and Japan took place in May 1960.During the struggle, he led the movement as one of the foremost thinkers in post-war Japan under the slogan "democracy or dictatorship".From 1963, he argued in favor of Mao Zedong and the Chinese Cultural Revolution in his magazine "Chugoku" published by Chugoku no Kai until the diplomatic normalization between Japan and the PRC (1972).