What are the consequences of inequality for subjective well-being? There are arguments both ethical and empirical suggesting that humans are or at least ought to be happier to live where there is more equality of opportunities and generally of outcomes as well. Beyond such direct links between inequality and subjective well-being, income inequalities have been argued to be responsible for damage to other key supports for well-being, including social trust, safety, good governance, and both the average quality of and equal access to health and education, – important, in turn, as supports for future generations to have more equal opportunities. Others have paid more direct attention to inequalities in the distribution of various non-income supports to well-being, without arguing that these inequalities were driven by income inequality.

If we are right to argue that broadening the policy focus from (traditional economic measures like) GDP to happiness should also entail broader measures of inequality, and if it is true that people are happier living in more equal societies, then we should expect to find that well-being inequality is a better predictor of average well-being levels than is the inequality of income.

Comparative evidence on the relative information content of different measures of inequality is relatively scarce. For international comparison of the prevalence of poverty, an important channel though which inequality affects well-being, it has been argued that people’s own subjective assessments of the quality of their lives, including access to food and other essential supports, should supplement and may even be preferable to the construction of poverty estimates based on the comparison of money incomes.

If people only pursued their own happiness, this would not produce a very happy society. Instead the greatest happiness principle exhorts us to care passionately about the happiness of others. It is only if we do so that true progress (as we have defined it) can occur.

What is so special about happiness?

Why not judge our progress by our wealth or our freedom or our health or education, and not just our happiness? Clearly many things are good.

But different goods are often in competition. Spending more on health may mean spending less on education. Or wealth-creation may require some limitations on freedom. So we have to ask why different things are good? And in most cases we can give sensible answers. For example, “Wealth makes people feel good” or “Ill health makes people feel bad”.

But if we ask why it matters how people feel, why happiness is good, we can give no answer. It is just self-evident. So happiness is revealed as the overarching good, and other goods obtain their goodness from the fact that they contribute to happiness. And that is why an “impartial spectator” would judge a state of human affairs by the happiness of the people. The greatest happiness principle has a universal appeal. It has the capacity to inspire, by mobilizing the benevolent part of every human being. Is there any prospect that we can achieve such a caring way of life?

Many people are skeptical. They believe that human nature is inherently selfish and we should just accept that fact. After all, it is the fittest who survive, and those must be the people who put no 1 first. But this crude form of Darwinism is quite contrary to the modern understanding of human nature and of human evolution, since it is the human instinct to cooperate which has given humans their extraordinary power over most other vertebrate species. The fact is that we have two natures, one selfish and one altruistic, and it is the function of our ethical culture to promote the altruist within us over the egotist.

In this context, an ethical system that favors not only others’ happiness but also our own has a much better chance of being implemented than one that is pure hair-shirt. It is therefore a huge advantage of the greatest happiness principle that it requires self-compassion as well as compassion towards others.

Sustainable development advocates, like Development Connect, claim that the happiness is achieved through a multi-dimensional focus on economic, social, and environmental objectives. The 17 Sustainable Development Goals (SDGs) express the idea that the “good society” should focus on the triple bottom line of economic prosperity, social inclusion, and environmental sustainability.

Happiness is the product of many facets of society. Income per capita matters, as economists emphasize, but so too do social conditions, work conditions, health, pollution, and values (e.g. generosity). The libertarian argument that economic freedom should be championed above all other values decisively fails the happiness test: there is no evidence that economic freedom per se is a major direct contributor of human well-being above and beyond what it might contribute towards per capita income and employment. Individual freedom matters for happiness, but among many objectives and values, not to the exclusion of those other considerations. Sustainable development and related holistic concepts (such as Pope Francis’s integral human development paper, 2015) are a better overarching guide to human wellbeing than the single-minded pursuit of income, or economic freedom, or other one-dimensional objective.

Jeffrey Sachs (World Happiness Report, 2016), at grave risk of trivialization, argued that various theories put different relative weights on six dimensions:

  • Mindfulness;
  • Consumerism;
  • Economic Freedom;
  • Dignity of Work;
  • Good Governance;
  • Social Trust.

He recognizes that the cause of human well-being is complex and not reducible to a single dimension. To achieve happiness requires the cultivation of mindfulness and virtue, to be sure; but it also requires an adequate command over material resources, as emphasized by economists; decent work; personal freedoms; good governance; and strong social ties.

While the language of the 2030 Agenda is about goals, timelines, human rights, and sovereign responsibilities, the agenda clearly embodies an implicit theory of human well-being, specifically that human well-being will be fostered by a holistic agenda of economic, social, and environmental objectives, rather than a narrow agenda of economic growth alone. As spelled out in the 17 Sustainable Development Goals, this implicit theory of happiness includes fighting poverty (SDG1), promoting gender equality (SDG5), emphasizing decent work for all (SDG8), narrowing gaps of income and wealth in society (SDG10), promoting environmental sustainability (SDG11, 12, 13, 14, 15), fostering peaceful and inclusive societies (SDG16) and enhancing global cooperation (SDG17).

Of course there are difficult and unsolved complexities in meeting these multi-dimensional challenges, especially in a world of 193 countries and 7.3 billion individuals.