Abstract
Population ethics is the subfield of philosophy that focuses on the moral aspects of how actions affect who exists in a particular population and what quality of life they have. The choices regarding what policies are adopted in response to climate change will affect the identities of those who exist in the future, the size of future populations, and the quality of life that future people will have. This chapter examines the nonidentity problem, various theoretical outlooks on population ethics, some recent policy proposals aimed at reducing fertility, and the relationship between population reduction and the impacts of climate change. After summarizing the relevant issues, the relevance of the discourse to climate policy is highlighted, and points of consensus and dissensus are noted. Disagreement on some of the key theoretical questions in population ethics is significant and poses a challenge for deriving meaningful conclusions about climate policy. Fortunately, emerging points of consensus on other aspects of climate policy and its relationship to population provide reasons to think moral decision-making about these matters is far from hopeless.