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)

Lexical views in population axiology can avoid the Repugnant Conclusion without violating Transitivity or Separability. However, they imply a dilemma: either some good life is better than any number of slightly worse lives, or else the ‘at least as good as’ relation on populations is radically incomplete. In this paper, I argue that Archimedean views face an analogous dilemma. I thus conclude that the lexical dilemma gives us little reason to prefer Archimedean views. Even if we give up on lexicality, (...) problems of the same kind remain. (shrink)

Population axiology concerns how to evaluate populations in terms of their moral goodness, that is, how to order populations by the relations “is better than” and “is as good as”. The task has been to find an adequate theory about the moral value of states of affairs where the number of people, the quality of their lives, and their identities may vary. So far, this field has largely ignored issues about uncertainty and the conditions that have been discussed mostly pertain (...) to the ranking of risk-free outcomes. Most public policy choices, however, are decisions under uncertainty, including policy choices that affect the size of a population. Here, we shall address the question of how to rank population prospects—that is, alternatives that contain uncertainty as to which population they will bring about—by the relations “is better than” and “is as good as”. We start by illustrating how well-known population axiologies can be extended to population prospect axiologies. And we show that new problems arise when extending population axiologies to prospects. In particular, traditional population axiologies lead to prospect-versions of the problems that they praised for avoiding in the risk-free settings. Finally, we identify an intuitive adequacy condition that, we contend, should be satisfied by any population prospect axiology, and show how given this condition, the impossibility theorems in population axiology can be extended to (non-trivial) impossibility theorems for population prospect axiology. (shrink)

This article articulates and defends a dissolution of the so-called repugnant conclusion, which focuses on the notion of life worth living figuring both in Parfit's formulation of the repugnant conclusion and in most responses to such a conclusion. The proposed dissolution demonstrates that the notion of life worth living is plagued by multiple ambiguities and that these ambiguities, in turn, hamper meaningful debate about both the issue of whether the repugnant conclusion can be avoided and the issue of whether the (...) repugnant conclusion is actually repugnant. This result does not exclude that some modified versions of the repugnant conclusion may yield valuable insights about the value of populations and the tenability of different axiological/ethical theories. Still, if the proposed dissolution is correct, then the repugnant conclusion rests on an ill-defined notion and we lack the information required to assess the merits of the repugnant conclusion. (shrink)

We examine a general class of variable-value population principles. Our particular focus is on the extent to which such principles can avoid the repugnant and sadistic conclusions. We show that if a mild limit property is imposed, avoidance of the repugnant conclusion implies the sadistic conclusion. This result generalizes earlier observations by showing that they apply to a substantially larger class of principles. Our second theorem states that, under the limit property, the axiom of mere addition also conflicts with avoidance (...) of the repugnant conclusion. This result is a consequence of a similar observation that appears in the earlier literature. (shrink)