IWATA Keiji (1922-2013) was among the first-generation lecturers who participated in the first postwar overseas survey of Southeast Asia. His academic background was in geography and he was graduated from the Faculty of Letters of Kyoto University. During the interwar period, when geopolitical theses were required to graduate, he started his research with a literature study of Aboriginal thought in Australia, in which he incorporated Émile Durkheim’s sociology methods of religion research and other disciplinary methods. While looking over the methodology of the German scholars, Carl Ritter and Alexander von Humboldt after the war, he applied their literature research methods in West Africa and Tonami-Gokayama regional research, both conducted in the Toyama Prefecture, at Osaka City University (now Osaka Metropolitan University). Later, he developed his theory of animism based on field surveys and observations in Laos, Thailand, Borneo, and other South Asian countries such as India, Sri Lanka, Nepal, and Bhutan. In his later years, he devoted himself to self-study pursuits. He worked at the Osaka City University, Tokyo Institute of Technology, National Museum of Ethnology and Otani University, and served as the president of the Ethnological Society of Japan, yet he was a solitary researcher who kept his distance from the currents of the Western cultural anthropology of the 1970s. From his student days, he had been interested in Buddhism, especially in the philosophy of Dogen(道元)，the founder of the Soto srect(曹洞宗). Based on the founder’s consideration of the natural and unnatural, pattern and ground, he insisted on self-participation and immersed himself in the subject where plants, insects, fishes, and people were all fused. This thought was fundamentally different from the Western dichotomous perception of nature and man, and it was also contrary to the Western cultural anthropological methodology and European geography of the time. Additionally, he adhered to a theory of animism with physiognomy and synchronicity. Ten years after his death, his work is being reevaluated from the ontological anthropology perspective. This short article presents oral materials and make some comments and annotates which illustrate Iwata’s attitude in the context of his long research history at the Asian Area Studies Group of the Human Geographical Society of Japan in 2004.