IB Philosophy 10.6.1 the Capabilities Approach: a New Metric for Justice and Development Key Definitions

Developed by Martha Nussbaum and Amartya Sen, the capabilities approach evaluates human well-being and social justice by measuring what people are actually able to do and to be, rather than what resources they formally possess. It holds that a just society must guarantee every person a sufficient threshold of real, effective opportunities across central areas of human life, including bodily health, education, political participation, and emotional expression.

In Aristotle's ethics, eudaimonia refers to human flourishing understood as the active exercise of distinctively human capacities in accordance with virtue over a complete life. Often translated as "happiness," it more precisely means living and faring well through the full realisation of what a human being is capable of becoming.

in Nussbaum's capabilities approach, the active realisations of capabilities, specifically what a person actually does or experiences, such as being well-nourished or participating in political life. Functionings are distinguished from capabilities, which are the real freedoms to choose those states: a person who fasts has the capability of nourishment, while a person who starves involuntarily does not. Justice requires securing capabilities (the option), not compelling specific functionings (the outcome), thereby respecting individual autonomy and pluralism.

Social contract theory is a tradition in political philosophy, associated with Hobbes, Locke, and Rousseau, that grounds political authority and justice in a real or hypothetical agreement among individuals to leave a state of nature and form a governed society. Classical versions assume parties are roughly equal in power, which critics such as Nussbaum argue excludes people with disabilities, non-human animals, and citizens of less powerful nations.