<p> The purpose of this paper is to clarify the thought of Shuichi Katsuta (1908-1969) on co-presence from the pre-war through wartime, and to define the limits of his thought.</p><p> Katsuta has been a far-reaching influence on educational thought after World War II in Japan; however, most researchers who have discussed Katsuta's thought have not considered his thought on co-presence. Therefore, this paper observes his thought on co-presence, and how it came about. The paper refers to the Kyoto School, especially Kitaro Nishida's philosophy and Tetsuro Watsuji's ethics, as the source of Katsuta's thought on co-presence.</p><p> This paper consists of the following sections:</p><p> 1. Introduction</p><p> 2. Survey of “I and We”</p><p> 3. Background of “I and We”</p><p> 4. Influence of Tetsuro Watsuji's ethics upon Katsuta's thought on co-presence</p><p> 5. Dilemmas of repetition of the past</p><p> 6. The loss of the other brought by recurrence to the origin</p><p> 7. Conclusion</p><p> The first section of the paper takes a general view of research on Shuichi Katsuta's thought, and confirms that existing research has not significantly considered his thought on co-presence.</p><p> The second section presents a survey of the thesis “I and We” (1938) that shows Katsuta's fundamental thought on co-presence.</p><p> The third section discusses the background of Katsuta's thought about co-presence from the pre-war through wartime. This section expresses that Kitaro Nishida's philosophy had a great influence on Katsuta's thought.</p><p> The fourth section searches for the influence of Tetsuro Watsuji's ethics upon Katsuta's thought on co-presence. This section shows that Katsuta discussed co-presence under the influence of Watsuji's ethics theories, and that the most important point of Katsuta's thought on co-presence was recurrence to the origin.</p><p> The fifth section considers the logic of recurrence to the origin. As with Watsuji's ethics, Katsuta considered that recurrence to the origin related to time. Surveying his thought on recurrence to the origin with time theory shows the core of his thought on co-presence.</p><p> The sixth section tries to define the limits of Katsuta's thought on co-presence. This section shows that the core of the problem of his thought on co-presence consists of recurrence to the origin itself.</p><p> The seventh section presents the conclusion and the issue of research into Katsuta's thought on co-presence after World War II.</p><p> As above, this paper discusses Shuichi Katsuta's thought on co-presence from the pre-war to wartime and defines the limits of his thought.</p>