Critical Levels and the (Reverse) Repugnant Conclusion

It is well-known that there is a trade-off among the properties of population principles that are used to make social evaluations when the number of people in the society under consideration may vary. The commonly used principles either lead to the repugnant conclusion (which is the case for classical utilitarianism), or they violate the Pareto-plus principle and related properties (average utilitarianism is an example of such a principle). This paper examines the nature of this trade-off and shows that the incompatibility between avoiding the repugnant conclusion and the Pareto-plus principle is fundamental and not restricted to the commonly used population principles.