In order to discuss the properties of human judgment and decision making in the risk society, a decision theoretic framework for evaluating uncertainties of several societal risks was introduced. There are controversies on the theoretical discussions about uncertainties related to the societal risks among scientists, sociologists, and also, possibly, the populace. Therefore, we introduced a taxonomy of the uncertainties from the standpoint of the environmental structure of decision makers, and examine the social risk problems as decision making problems uncertainties using it. Secondly, we also introduced prospect theory as a nonlinear expected utility theory in order to examine human judgment and decision making and normative societal decision theory. We proposed to apply prospect theory as a non-linear expected utility theory for the evaluation of risks especially for natural disasters, nuclear power plants, and other new technologies. Lastly, we introduced the properties of human social behavior and trust formation in the modern uncertain world, and then discussed practical implications of our framework for risk evaluation as a process of social technology for social safety and security.
