Sufficientarian accounts of intergenerational justice have recently gained more popularity. These accounts require that in just distribution all persons should enjoy some minimum threshold of basic needs, rights or wellbeing. Moreover, sufficientarianism typically holds generational neutrality, i.e., the view that the moral weight of persons’ basic needs, rights or wellbeing should be the same regardless of what generation these persons belong to. On the basis of generational neutrality, intergenerational sufficientarians have argued that there are no defensible justifications for the employment of “pure time discounting”.
However, while intergenerational sufficientarians defend generational neutrality regarding people’s basic needs, rights or wellbeing up to the minimum threshold, they may accept temporal discounting on some other grounds. Uncertainty concerning future basic needs or wellbeing might be one possible justification. Another one may concern the just savings rate between generations that would be required to guarantee the minimum threshold for all. For instance, some accounts seem to require rather high savings rate from the current and following generations in order to recover a relatively stable atmosphere, whereas once climate sustainability has been achieved the savings rate could later be more moderate.
These questions lead us to investigate the other “fundamental ethical parameter” of the social discount rate, namely the elasticity of marginal utility. Our aim in this paper is to analyze how the particular climate-relative specifications of minimum threshold assumed by various intergenerational sufficientarian accounts may support different views about the choice of the elasticity of marginal utility and the social discount rate respectively. Since the elasticity of marginal utility can be fitted in a number of economic models, the significance of these considerations extends beyond the cost-benefit analysis of mitigation policies and should be explored also in other contexts.
