Shackle was one of the representative critics of probability calculus. His alternative decision theory was mathematically reformalized by Katzner till 1990s. Following the Katzner’s reformalized framework, this paper presents a new interpretation of Shacklean theory by focusing on the common stage structure of the decision-making. This paper shows that the characteristics of Shackle-Katzner framework can be explained as: (1) the non-distributive and non-additive ordinal measure of subjective uncertainty, (2) the incomplete list of imaginable future states, (3) the valuation of “importance” reflecting various types of loss- psychology, and (4) the final choice of the action is made on the set of importance intervals. The purpose of this paper is to investigate how the foundational stance of Shackle-Katzner framework about the decision-making elicits the different formal structure, and to provide a new interpretation of Shacklean decision theory.