On parity views of mere addition if someone (or a group of people) is added to the world at a range of well-being levels – or ‘neutral range’ – leaving existing people unaffected, addition is on a par with the initial situation. Two distinct parity views – ‘rough equality’ and fitting-attitudes views – defend the ‘intuition of neutrality’. The first can be interpreted or adjusted so that it can rebut John Broome's objection that the neutral range is wide. The two views respond in distinct ways to two of Broome's other objections. Both views can, nonetheless, be plausibly defended against these objections.

In criticizing communitarian views of justice, Amartya Sen argues that identity is not merely a matter of discovery but an object of reasoned choice subject to constraints. Distinguishing three notions of identity – self-perception, perceived identity and social affiliation – I claim that the relevant constraints implied by this argument are minimal. Some of Sen's arguments about perceived identity and social context do not establish any further constraints. Sen also argues that a model of multiculturalism and some forms of education can restrict, or fail to promote, reasoned and informed identity choice. This argument is better understood in the light of Sen's work on capability and justice, notably his concern with ways in which underdogs can adapt and his emphasis on public reasoning. It highlights limitations on information and opportunities for reasoning. I suggest that these lead to genuine constraints on (reasoned and informed) identity choice. The paper focuses on Sen's work, though its claims are also relevant to George Akerlof and Rachel Kranton's analysis of identity.

In comparing Sen's work with Mill's, Sugden criticizes Sen's capability approach because it may be applied in such a way that society or theorists judge what is best for people and potentially restrict liberty on that basis. Sugden cites Nussbaum's work as evidence in making his case. Sugden's critique of Sen's approach succeeds on a narrow reading of it. On that reading Sen is also critical of it because it does not leave enough room for liberty. On a broad reading, the critique has less force. Nussbaum's approach follows Mill in allowing people freedom to act on whatever desires they have if this does not harm others. This neutralizes the central element of Sugden's critique as it applies to her approach to some degree. Both Sen and Nussbaum nonetheless recognize the danger of illiberal restrictions in application which motivates Sugden's critique.

The concept of well-being is central to the subject matter of moral philosophy as well as economics. According to some moral theorists (particularly utilitarians) morality is about the maximization of social well-being. According to others, notably John Rawls (1972) we ought to give particular priority to the worst off members in society. Both these and other moral positions, whatever the priority they attach to different members of society in arriving at moral judgements, require an account of well-being or advantage. The concern with well-being is thus of foundational importance in moral philosophy, even if well-being is not thought of as all that matters. Furthermore, those who want to distinguish ‘morality’ from ‘self-interest’ must furnish us with an account of human interests, so that we can distinguish the moral realm from that of self-interest or prudence. The concerns of moral philosophers, here, clearly overlap with those of economists. Economists (particularly in welfare and development economics) are much concerned with questions of how well people are doing, with their ‘standard of living’ or ‘quality of life’. However, there are very different ways of thinking about each of these ideas. Indeed, we need to discriminate between different views of the quality of life and to decide which is the most appropriate for the purposes of moral theory and the normative parts of economics.