I work on the following broad set of issues. For a full list of my publications, see my CV.

Age, demography, and the global burden of disease

It is bad if many people die of preventable causes. But how bad is premature mortality for a population? In The Value of Longevity, I develop a theory of the harm of population mortality. It was in part inspired by the way the Global Burden of Disease project (GBD) calculates years of life lost due to premature mortality. (For an overview, see QALYs, DALYs, and Their Critics.) The GBD used to give different weights to death and disability at different ages, a practice I criticized in Age-Weighting. Although there is no explicit age-weighting in the GBD any more, a form of implicit age-weighting is still present, as I argue in Age and Time in the Measurement of the Burden of Disease.

It is not clear, however, that this form of age-weighting must be rejected. In Fair Innings, I defend the idea that more weight should be given to an additional year of life for a younger person than an older person. (I provide an overview of the debate in Priority Setting and Age.) With Sam Kerstein, we defend the permissibility of giving priority to the young on Kantian grounds as well in Saving Lives and Respecting Persons, and we argue, in Complete Lives in the Balance, that our account has advantages over other ethical frameworks for saving lives in emergencies (such as a pandemic).

If people don’t die of preventable causes and many children are born, then we have to face the problem of overpopulation. If it gets really bad, what can we do? In Overpopulation and Procreative Liberty, I discuss two proposals: mandatory long-term contraception and tradeable procreation entitlements (roughly, markets for parenting rights). Contrary to what almost everyone believes, these proposals not only do not conflict with personal autonomy and liberty, but can actually increase them.

Equality, priority, and responsibility

Many philosophers are luck egalitarians: they believe it is in itself bad if some people are worse off than others through no fault or choice of their own. But on this view, it is not in itself bad if some are worse off through their own fault or choice – that is, when they are responsible for their misfortune. In Catering for Responsibility: Brute Luck, Option Luck, and the Neutrality Objection to Luck Egalitarianism, I show that the way luck egalitarians think about responsibility is deeply problematic. This is not just a theoretical problem. The Mismarriage of Personal Responsibility and Health illustrates how the influence of luck egalitarianism can distort health policy.

My favored view of distributive justice is prioritarianism, which says, roughly, that benefiting a person matters more the worse off that person is. (This gives no role to equality, since what matters is not how you fare compared to others, but how badly off you are in absolute terms.) Egalitarians have attacked this view, in part, by building arguments from the claim that common-sense morality is egalitarian, since empirical surveys on people’s preferences in health care resource allocation problems correspond to egalitarianism, rather than prioritarianism. In Empirical and Armchair Ethics, I explain that this kind of argument is based on a misunderstanding of the empirical data, and if anything, common-sense morality is closer to prioritarianism than to egalitarianism.

It’s not that inequalities don’t matter. We are on the cusp of a biotechnological revolution, and soon we might be able to genetically engineer ourselves to have longer, healthier, and better lives. In the future, biotechnology will massively improve population health, but the benefits will be unequally distributed. Enhancement and Equality maps out these issues. But the correct ethical response to the moral problems of the future is to adopt prioritarianism, rather than egalitarianism. I show this for the case of climate change in Can the Maximin Principle Serve as a Basis for Climate Change Policy?

Priority setting, disability, and quality of life

Because Scarcity is unavoidable, priorities must be set. This is especially true in health policy. The most important analytical tool to help manage scarcity in health care is cost-effectiveness analysis (CEA). But many people worry: Does Cost Effectiveness Analysis Unfairly Discriminate Against People with Disabilities? My view is that it does not; standard examples of disability discrimination are based on misunderstandings of CEA, as I argue in Cost-Effectiveness Analysis and Disability Discrimination. When health care priority setting disadvantages people with disabilities, it should be dealt with as a matter of justice (and thus prioritarianism can be applied), instead of as a matter of wrongful discrimination.

Surprisingly, my views on disability are somewhat controversial, insofar as I think that disability is bad for you. That’s because more and more philosophers argue that disability is “mere difference,” and rather than treated as a harm, it should be considered and even celebrated as just another manifestation of human diversity. Is Disability Mere Difference? defends the view that disability is, indeed, bad for you. Fairness and the Puzzle of Disability shows that it also raises paradoxes for ethical theory.

Controversies about disability lead to broader issues about well-being or the quality of life. Many philosophers, and most quality of life researchers, argue that well-being or quality of life is “subjective”: people’s own evaluations (their preferences, happiness, or judgments of life satisfaction) have an indispensable role both in conceptualizing and measuring it. In The Concept of Quality of Life, I argue that things are more complicated than this. Of course, there are philosophers who defend subjective theories of well-being; Authentic Happiness argues against a prominent hedonist theory and Welfare Judgments and Risk shows how even the most plausible preference-based theories run into problems once risk is taken into account.