Abstract

In the brilliant final section of Reasons and Persons , Derek Parfit presents a puzzle about how the goodness of states of affairs relates to the quality of the lives led by people in those states. Stripped to barest essentials, the puzzle runs as follows: if the value of a state is obtained simply by aggregating the quantity of whatever makes life worth living, then a world in which a significant number of people (say ten billion) enjoy lives of very high quality would be inferior to a world in which a vastly greater number of people have lives that are barely worth living (the..