Policy design by "imaginary future generations" with systems thinking : a practice by Kyoto city towards decarbonization in 2050

To achieve the societal goal of becoming a sustainable decarbonized society by 2050, it is essential to design visions and policies that take into account the perspectives of future generations overcoming intergenerational conflicts. In this paper, we present an innovative framework to envision a decarbonized society in 2050 and design policies by introducing "imaginary future generations," together with systems thinking, and analyze the effectiveness of these methods. We organized a series of workshops in which Kyoto City officials participated in the application of the framework. We demonstrate that by applying the framework, the policy measures proposed by the participants shifted from individual measures to proposals of new mechanisms and systems that do not yet exist, even if they present high hurdles for the current generation. Causal loop diagrams based on system thinking proved to be effective for increasing liveliness, reducing divergence, and improving the development of discussion themes. A questionnaire survey revealed that the workshop produced shifts in the participants' perceptions. We conclude that the proposed framework effectively generated "futurability" in the participants and could help facilitate policy design that aims to achieve a decarbonized society by overcoming the shortsightedness of the present society.