This supplement consists of four parts: (i) the robustness of findings in the main paper with respect to several main assumptions, (ii) an alternative nterpretation of intergenerational Pareto and its implication on quasi-hyperbolic discounting, (iii) a result with forward and backward individual exponential discounting, and (iv) a discussion of the choice domain of the main paper. The supplement uses definitions and notations from the main paper.