In 1952, he graduated the Department of Mathematics, the Faculty of Science, the University of Tokyo, and obtained his Bachelor of Science.[1] That same year, he was appointed Assistant Professor in the Department of Mathematics of the University of Tokyo.[1] He obtained his Doctor of Science (DSc) degree from the University of Tokyo in 1961,[3] under the direction of Shokichi Iyanaga. In 1962, he was appointed Associate Professor in the Faculty of Science at Gakushuin University, and was promoted in 1966 to the rank of Professor. He became a professor of Theoretical Foundation of Information Science in 1972. After retiring from the University of Tokyo in 1990, he moved to Tokyo Denki University.
^Koster, Cornelis H. A. (25–28 June 1996). "The Making of Algol 68". In Bjørner, Dines; Broy, Manfred; Pottosin, Igor V. (eds.). Perspectives of System Informatics: Second International Andrei Ershov Memorial Conference, Proceedings. Lecture Notes in Computer Science. Vol. 1181. Akademgorodok, Novosibirsk, Russia. pp. 55–67. doi:10.1007/3-540-62064-8_6. Especially see p. 61.