Abstract
As the title of this paper indicates, I’m going to discuss what we ought to do in situations where our actions affect future generations. More specifically, I shall focus on the moral problems raised by cases where our actions affect who’s going to live, their number and their well being. I’ll start, however, with population axiology. Most discussion in population ethics has concentrated on how to evaluate populations in regard to their goodness, that is, how to order populations by the relations “is better than” and “is as good as”. This field has been riddled with “paradoxes” which purport to show that our considered beliefs are inconsistent in cases where the number of people and their welfare varies. Derek Parfit’s Mere Addition Paradox is a case in point. The main question of my paper concerns the implication of such axiological paradoxes for normative theories. Do the axiological paradoxes translate into paradoxes for normative theories or will they, as some believe, disappear if we switch to a normative framework?