According to the procreation asymmetry, we have strong pro tanto reason to do what prevents someone from coming into a miserable existence—an existence so bad that it would be rational to prefer having never been born—solely because it prevents them from coming into a miserable existence, but we do not have strong pro tanto reason to do what allows someone to come into a happy existence solely because it allows them to come into a happy existence. At best, the fact (...) that an act would create a happy person merely offsets the reasons we have to avoid that act—i.e., an act that would be impermissible because it brings a miserable person into existence could be rendered permissible if it also brought into existence enough happy people. In this paper, I first argue that there is an intuitive asymmetry in the offsetting weight of happy humans and the offsetting weight of happy animals: the offsetting weight of happy animal lives vis-à-vis miserable animal lives appears to be greater than the offsetting weight of happy human lives vis-à-vis miserable human lives. This is the Procreation Asymmetry Asymmetry. I then argue that there is no Procreation Asymmetry Asymmetry. The best explanation of why happy human lives have only weak offsetting weight implies that happy animal lives also have only weak offsetting weight. (shrink)

Person-affecting views in population ethics state that (in cases where all else is equal) we’re permitted but not required to create people who would enjoy good lives. In this paper, I present an argument against every possible variety of person-affecting view. The argument takes the form of a dilemma. Narrow person-affecting views must embrace at least one of three implausible verdicts in a case that I call ‘Expanded Non-Identity.’ Wide person-affecting views run into trouble in a case that I call (...) ‘Two-Shot Non-Identity.’ One plausible practical upshot of my argument is as follows: we individuals and our governments should be doing more to reduce the risk of human extinction this century. (shrink)

This thesis consists of a series of papers in population ethics: a subfield of normative ethics concerned with the distinctive issues that arise in cases where our actions can affect the identities or number of people of who ever exist. Each paper can be read independently of the others. In Chapter 1, I present a dilemma for Archimedean views in population axiology: roughly, those views on which adding enough good lives to a population can make that population better than any (...) other. In Chapter 2, I extend Gustaf Arrhenius’s famous impossibility theorems in population axiology into the domain of choices under risk. My risky impossibility theorems dispense with the assumption that welfare levels are finitely fine-grained, and so tell against lexical views in population axiology. In Chapter 3, I present objections to critical-level and critical-range views in population axiology. I then sketch out what I call the ‘Imprecise Exchange Rates View’ and argue that it is an attractive alternative. In Chapter 4, I address critical-level and critical-range views again. This time, I note that they are vulnerable to objections from biographical identity: identity between lives. I suggest that these objections give us reason to reject critical-level and critical-range views and embrace the Total View. In Chapter 5, I argue that objections of the same form – objections from personal identity – tell against person-affecting views in population ethics. In Chapter 6, I draw out some counterintuitive implications of two recent complaints-based theories of the procreation asymmetry. (shrink)