What Can You Actually Do? The Capability Approach to Well-Being

Imagine two kids in the same classroom. They both get the same backpack at the start of the year, with the same supplies: pencils, notebooks, a calculator, the same textbook. Now imagine that one of them needs glasses to read the board, but doesn’t have them. The other kid has perfect vision. Same backpack, same supplies — but very different abilities to actually learn, participate, and succeed.

This is the kind of puzzle that the economist-philosopher Amartya Sen started thinking about in the 1970s, and it led him to develop what’s now called the capability approach. The core idea is simple but powerful: when we’re trying to figure out whether someone is doing well in life, we shouldn’t just look at what stuff they have. We should look at what they can actually do and be with that stuff. That’s what “capabilities” are — your real, substantial opportunities to be the person you want to be and do the things you want to do.

The Problem with Just Looking at Stuff

Most ways of measuring well-being focus on the means — the resources people have. Does a person have enough money? Enough food? A good school nearby? These things matter, Sen agrees. But they’re not the whole story, because people differ dramatically in their ability to turn those resources into actual achievements.

In a famous lecture called “Equality of What?”, Sen asked us to consider two people with the same amount of resources. One of them has a disability that requires her to spend a lot of her resources just to get around — maybe on a wheelchair, or on medical care. The other person is able-bodied and can spend all his resources pursuing whatever he values. Are they equally well-off? Obviously not. The disabled person has to work much harder just to achieve the same basic doings and beings — like being able to move around, or being in good health.

Here’s another twist. Suppose you try to measure well-being by how happy or satisfied people feel. This is what utilitarians do. Sen points out a problem: people who are used to being deprived often lower their expectations. A person living in extreme poverty might report being “satisfied” because she’s learned not to hope for more. Meanwhile, a wealthy person who’s hard to please might report being unhappy. If we use happiness as our measure, we might end up giving more resources to the already-comfortable person and less to the person who actually needs help. That seems deeply unfair.

The capability approach says: instead of looking at happiness or at resources, look at the real opportunities people have to achieve the things that matter.

What Are “Functionings” and “Capabilities”?

The capability approach works with two closely related ideas.

Functionings are the actual “doings and beings” a person has achieved. Being well-nourished. Being educated. Being able to move around. Having friendships. Taking part in community life. These are the things that make up a human life.

Capabilities are the real opportunities a person has to achieve those functionings — the set of possible lives they can actually choose from. A person might have the capability to be well-nourished (enough food is available, she can access it, her body can digest it properly) even if she chooses to fast for religious reasons. Her functioning is “fasting,” but her capability includes being nourished.

Capabilities, Sen emphasizes, are real freedoms — not just formal rights on paper. You might have the legal right to vote, but if the nearest polling station is 200 kilometers away and you have no transportation, you don’t really have the capability to vote. You might have the formal freedom to become a doctor, but if your family can’t afford medical school and no scholarships exist, that opportunity isn’t real.

What Makes a Capability Real?

Whether you can turn a resource into a functioning depends on something Sen calls conversion factors. These are the conditions — inside you and around you — that help or hinder your ability to convert stuff into actual opportunities.

There are three main kinds:

Personal conversion factors are about you as an individual. Your metabolism, your physical condition, your skills, your intelligence. A bicycle enables the functioning of mobility — but only if you’ve learned to ride, if your legs work, if you’re not too ill to pedal.

Social conversion factors are about the society you live in. Laws, cultural norms, discrimination, power relations. In some societies, women are not allowed to ride bicycles. In that case, even if a woman owns a bike, she doesn’t really have the capability to ride it freely.

Environmental conversion factors are about the physical world around you. Climate, roads, infrastructure, pollution. Living in the Netherlands — with its bike lanes and flat terrain — gives you a much better chance of actually using a bicycle for transportation than living in a city built entirely for cars on steep hills.

All these factors together determine whether a resource actually becomes a real opportunity. This is why the capability approach insists we need to know a lot about each person’s specific situation before we can say whether they’re well-off.

Why Focus on Ends, Not Means?

The capability approach makes a sharp distinction between means and ends. Money, goods, infrastructure — these are means. They’re tools. What ultimately matters, for the capability approach, are the ends — the actual capabilities and functionings that make a life go well.

This might sound like a small shift, but it has big consequences. For one thing, it means we don’t end up treating money or economic growth as valuable in themselves. They’re only valuable if they actually expand people’s real freedoms. A country might get richer while some groups — say, people with disabilities, or women in highly unequal societies — see their capabilities shrink. The capability approach catches that.

It also means we don’t assume that the same means work for everyone. If you want to improve people’s health, you might need to think about more than just building hospitals. You might need to address social norms that make some people afraid to seek care. You might need clean water, or better roads to reach clinics, or education about nutrition. The right combination of means depends on what’s blocking people’s capabilities in the first place.

Acknowledging Human Diversity

One reason the capability approach has been popular among feminist philosophers and disability advocates is that it takes human diversity seriously. Many standard theories of justice or well-being assume a “normal” person — an able-bodied, independent adult who can convert resources into well-being pretty easily. But many people don’t fit that picture.

The capability approach doesn’t treat those people as exceptions or afterthoughts. Their different needs, different bodies, different circumstances are built into the framework from the start. The question is never just “does everyone have the same resources?” but “does everyone have the real freedom to achieve the things that matter, given their particular situation?”

This also connects to something Sen calls agency freedom. People don’t just want to be well-off in some abstract sense. They want to pursue their own goals and values. Two people might have the same capability set — the same real opportunities — and make very different choices about which functionings to realize. The capability approach respects that. It values the freedom to choose, not just the achievement of some predetermined list of good things.

How Do We Decide Which Capabilities Matter?

This is where the approach gets complicated — and where philosophers disagree.

Martha Nussbaum, another key thinker in this tradition, argues that we can identify a specific list of “central human capabilities” that every government should guarantee to its citizens. Her list includes things like life, bodily health, bodily integrity, senses/imagination/thought, emotions, practical reason, affiliation, play, and control over one’s environment. She argues that these capabilities are essential for a life with human dignity.

Amartya Sen takes a different approach. He refuses to draw up a fixed list, arguing that communities and groups should decide for themselves which capabilities matter in their context. He worries that an outside philosopher’s list might impose one particular vision of the good life on people who don’t share it. Instead, he emphasizes democratic deliberation and public reasoning.

This debate is still very much alive. Some capability scholars think Sen is too vague — that without some way to prioritize capabilities, we can’t make the hard choices that justice requires. Others worry that Nussbaum’s list is too rigid, or that it doesn’t leave enough room for people to decide what matters in their own lives.

An Open Question: Capabilities or Functionings?

Here’s another tricky question: when we’re comparing how well-off people are, should we look at their capabilities (the opportunities they have) or their functionings (what they actually achieve)?

There are good arguments on both sides. Looking at capabilities respects people’s freedom to choose. If someone chooses to fast, they’re not deprived — they have the capability to be nourished but exercise their freedom not to be. Looking only at functionings would wrongly count them as badly off.

But sometimes capabilities are hard to see. It’s much easier to observe whether someone is well-nourished than to know whether they could be well-nourished if they chose. And for some people — infants, people with severe dementia — the distinction between capability and functioning may not make much practical sense. We don’t really care whether a baby has the opportunity to be nourished; we care that she actually is nourished.

And there’s a trickier problem: some capabilities are conditional on what other people choose. Two parents might each have the capability to hold a demanding job — but if they also have a baby who needs care, only one of them can actually realize that capability at a time. In cases like this, just knowing that each parent has the opportunity in the abstract doesn’t tell you enough about their real situation.

Why This Still Matters

The capability approach has been hugely influential — not just in philosophy, but in how international organizations like the United Nations think about development. Every year, the UN’s Human Development Report measures countries not just by their wealth, but by indicators of health, education, and other capabilities. This shift — from asking “how rich are they?” to asking “what can they actually do and be?” — is a direct result of Sen’s work.

But the approach also raises deep questions that are still being debated. How do we weigh different capabilities against each other? Is it okay to sacrifice some capabilities (say, environmental sustainability) for others (say, economic opportunity)? Who gets to decide? Can the capability approach handle justice for future generations, or for non-human animals?

These aren’t just abstract puzzles. They’re questions about what we owe each other, and about what a genuinely good life looks like. The capability approach doesn’t give final answers, but it gives a powerful way to ask the questions — by insisting that we keep our eyes on what people can actually do and be, not just on the stuff they happen to have.

Key Terms

Term	What it does in this debate
Capability	Your real, substantial opportunity to achieve a certain doing or being
Functioning	An actual “doing or being” that you’ve achieved (being nourished, being educated, etc.)
Conversion factors	The conditions (personal, social, environmental) that affect whether you can turn a resource into a capability
Means	The resources and goods you have — valuable only as tools for achieving capabilities
Ends	The capabilities and functionings that ultimately matter for well-being
Real freedom	Freedom that’s substantive — you have all the necessary conditions to actually do or be something, not just the formal right

Key People

Amartya Sen: An economist and philosopher from India who pioneered the capability approach. He argued that well-being should be measured by what people can actually do and be, not just by their resources or happiness.
Martha Nussbaum: An American philosopher who developed her own version of the capability approach, with a specific list of ten central capabilities that she thinks every government should guarantee. She also applies the approach to animal rights.

Things to Think About

Sen argues that people living in deprivation often lower their expectations, so their reported happiness can be misleading. But if you were in charge of deciding what people need, wouldn’t you risk imposing your own values on them? How do you decide when to trust people’s own reports of their well-being and when to override them?
Nussbaum’s list of central capabilities includes “play” and “affiliation” alongside more obvious ones like “life” and “health.” Does that seem right to you? Should every person on earth be guaranteed the opportunity to play? What about things not on her list — like the capability to practice your religion, or to create art?
Think about your own school. If you measured how well it’s doing by looking only at resources (budget per student, number of computers, size of library), what might you miss? What would you need to know about each student’s conversion factors to really understand whether they have the capability to learn?
The capability approach focuses on individual opportunities. But some things that matter — like friendship, or political protest, or playing in a band — can only be done together with other people. Can an approach that starts with individuals really capture these shared capabilities?

Where This Shows Up

Human Development Index (HDI): Every year, the United Nations ranks countries using a measure that includes not just income but also life expectancy and education — directly inspired by Sen’s capability approach.
Public health: Organizations like the World Health Organization use capability thinking to argue that health isn’t just about treating disease but about giving people the real opportunity to live flourishing lives.
Disability advocacy: The capability approach provides a framework for arguing that what matters isn’t just giving disabled people the same resources as others, but removing the social and environmental barriers that block their real opportunities.
Your own life: Next time someone asks “what do you want to have?” try asking instead “what do I want to be able to do and be?” The shift from means to ends can change how you think about your own goals.