Prioritarianism in practice

"Prioritarianism is a framework for ethical assessment that gives extra weight to the worse off. Unlike utilitarianism, which simply adds up well-being numbers, prioritarianism is sensitive to the distribution of well-being across the population of ethical concern. Prioritarianism in Practice examines the use of prioritarianism as a policy-evaluation methodology-across a range of policy domains, including taxation, health policy, risk regulation, climate change, education, and responses to the COVID-19 pandemic-and as an indicator of a society's condition (as contrasted with GDP). This chapter is an introductory chapter to the Prioritarianism in Practice volume. It surveys the intellectual roots of prioritarianism: in the philosophical literature, in welfare economics, and in scholarship about public health. And it provides brief summaries of each of the volume's chapters. This chapter provides theoretical foundations for the Prioritarianism in Practice volume, by clarifying the features of prioritarian social welfare functions (SWFs). A prioritarian SWF sums up individuals' well-being numbers plugged into a strictly increasing and strictly increasing transformation function. Prioritarian SWFs, like the utilitarian SWF, fall within the "generalized utilitarian" class of SWFs. Generalized-utilitarian SWFs are additive and, hence, especially tractable for purposes of policy analysis. The chapter reviews the axiomatic properties of generalized utilitarian SWFs and, specifically, of prioritarian SWFs. Prioritarianism satisfies the Pigou-Dalton axiom (a pure, gap-diminishing transfer of well-being from a better-off to a worse-off person is an ethical improvement), while utilitarianism does not. Pigou-Dalton is the axiomatic expression of the fact that a prioritarian SWF gives extra weight (priority) to well-being changes affecting worse-off individuals. The chapter also discusses the informational requirements of prioritarian SWFs (as regards interpersonal well-being comparisons). It reviews the various methodologies for applying a prioritarian SWF under uncertainty. And it describes the two main subfamilies of prioritarian SWFs, namely Atkinson and Kolm-Pollak SWFs"--