This article aims to scrutinize the contents of two papers published in 1951 by Masanao Toda, the one arguing a general framework for human behavior and the other concerning a measurement of intuitive probability. Although Masanao Toda is recognized as a pioneer of cognitive science in Japan, his works prior to those on cognitive science are not familiar to the Japanese cognitive science community; thus, the fact, that he was also a pioneer of decision-making research in Japan, is not sufficiently recognized. This paper demonstrates several interesting and ingenious features of the two papers published early in Toda's career that concern an issue of intuitive judgment in terms of research trends both in those days and since. Finally, this paper also argues for the significance of examining Toda's studies in reconsidering the origin of both behavioral economics and cognitive science.