A group of seven intellectuals, led by Shunsuke Tsurumi, founded a journal entitled The Science of Thought (Shisô no kagaku) in 1946 in Japan under the occupation by the American General Headquarters (GHQ). In this paper I will study the collective research on the political conversion of Japanese intellectuals in the war period by analyzing some impacts of William James, especially his Varieties of Religious Experiences.

The first part of the paper is a short introduction of The Science of Thought and the background of the collective research on the political conversion. Taking a distance from the discourses on democracy promoted by American occupation policy, the journal tried to make a communication between philosophy and daily life of Japanese people in order to avoid the superficial use of ideas such as “liberty” and “equality”. It was a criticism of the modern Japanese intellectuals who tried to enlighten the people with imported European philosophy and came to support the military regime. Shunsuke Tsurumi was a leading founding member of The Science of Thought. He learned at Harvard University between 1939 and 1941, took classes of Ralph Barton Perry and learned logical positivism under his tutor W.V.O. Quine. After the regrettable war experience, he advanced his reflection on the facts that the Japanese people, who had supported the war regime by repeating slogans against devil Americans, was changing quickly its attitude by accepting superficially the democratic ideas dispersed through the US occupation. In the early period of fifty years of its history (1946-1996), the journal introduced American philosophy in post‑war Japan.

Pragmatism played an important role in the journal's activities: most of its contributors were interested in describing the life of “ordinary people” in Japan. The pluralism was a policy of the journal, wishing to create a liberal place by supporting spontaneous exchanges. The journal activities , overlapping with other social movements, developed its form like an undefined association of “circles” based on their interests For example, Kazuko Tsurumi, the sister of Shunsuke Tsurumi and a founding member of Shisô no kagaku, participated in a circle for the life writing by housewives, in which people learned “non-professional life writing” (Seikatsu tuzurikata) in order to improve the living conditions. (There were many groups of this sort.) Then this activity of life writing became a part of the Collective Research on Political Conversion (Kyôdô kenkyu Tenkô) (1959-1962) pursued during eight years by around twenty members of Shisô no kagaku.

Recalling their work to make a record about the urged conversions of the Japanese intellectuals under militarism, Shunsuke Tsurumi said “ by taking a distance from the existing method of the history of ideas, which followed up the achievement of one's thought, we tried to describe how an individual transformed one's own thought through the opposition with the state. The methodology for that purpose was firstly to examine the existing method to make a record of conversion not only in contemporary America, Britain, Germany and Italy but also in the documents since the Roman Empire, to attempt to situate in this frame of the conversion what is happening in Japan and what is happening in myself.” In other words, “the motive of the research project consisted in being aware of how Japanese liberal intellectuals had corrupted collectively and in making a record of their way of corruption” (S.Tsurumi, 2001, “Buried in a piece named as nation”, Rethinking on Conversion, 2001 pp.10-11).

The second part of the paper analyses the methodology of the research on political conversion. The introduction of the Collective Research on Political Conversion written by Shunsuke Trusumi explained the possible typology of conversion as a grid in order to grasp the conversion of the intellectuals and re-describe their personal history from their works and other documents. Tsurumi, who had submitted his graduation dissertation on the pragmatism of William James before leaving US in 1942, considered James' descriptive study as a guide to his later work. Although James is not explicitly mentioned in the methodology, James study on religious experiences in The Varieties of Religious Experience indeed had a certain influence on the method of political conversion analyses.

To illustrate James' impact on the Collective Research on Political Conversion, I will try to give a comment on two chapters of the first volume (prewar period) written by a pragmatist Uozu Ikuo : “A public activist, Takakurateru” and “A left-wing liberal intellectual, Kiyoshi Miki”. Uozu's description about those two intellectuals introduces the two types of conversion, which can be comparable with James' famous model of “sick-soul” and “healthy mindedness” types in religious experience. It will allow us to understand James' influence on the social thoughts in the context of pacifism in the post-war Japan.