How should we compare welfare across pension systems in presence of differential mortality? A commonly used standard utilitarian criterion implicitly favors the long-lived over the short-lived. We investigate under what conditions this ranking is reversed. We clearly distinguish between the redistribution along mortality and income dimensions, and thus between mortality and income progressivity. We show that when mortality is independent of income, mortality progressivity can be optimal only when (i) there is more aversion to inequality in lifetime utilities compared to aversion to consumption inequality, (ii) life is valuable. When the short-lived tend to have lower income, mortality progressivity can be also optimal when income redistribution tools are limited. In this case, mortality progressivity is used to substitute for income progressivity.