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What is justice?
asked since c. 375 BC· Big question· Politics, society & justice
Mostly agreedGood evidence; some details uncertain.
The question of what people owe each other, and how a society should share out goods, burdens, rights and punishments.
See it on the Philosophy map →The idea
Answers fall into families. Justice as power: rules serve whoever makes them (Thrasymachus). Justice as harmony: everyone doing their proper part (Plato). Justice as desert: giving each their due, treating equals equally (Aristotle). Later came justice as the greatest good for the greatest number (utilitarians), as fair rules chosen behind a 'veil of ignorance' (Rawls), and as respect for free exchange (Nozick). A concrete test: should a bonus pool be split equally, by contribution, or by need?
Why it matters
Every tax code, court sentence and wage policy assumes some answer, and the competing answers still define much of political disagreement.
Where it comes from
Traced through texts: Plato's Republic, Aristotle's Nicomachean Ethics Book V, Rawls's A Theory of Justice (1971) and Nozick's Anarchy, State, and Utopia (1974).
Still debated
Whether justice is one standard for all people or varies by culture, and whether equality, merit or need should win when they conflict.
Connections (5)
▸The Sophists (Protagoras, Gorgias) gave a power-based answer to What is justice?Mostly agreed
The connection
Sophists contrasted nature (physis) with convention (nomos): laws are human agreements, not cosmic truths. Some drew a hard conclusion. In Plato's Republic, Thrasymachus says justice is 'the advantage of the stronger', rules written by rulers for their own benefit. Plato's whole account of justice was built to answer that challenge.
When and how
Athens in the late 5th century BC, during the Peloponnesian War; voiced by Thrasymachus of Chalcedon and Antiphon, and by Callicles in Plato's Gorgias.
How sure are we?
Fragments of Antiphon's On Truth survive on papyrus; Thrasymachus's view is known mainly from Plato, a hostile witness.
Debates and open questions
Whether the Sophists shared any one view: Protagoras taught that everyone needs a sense of justice, and Plato may have made the movement look more cynical than it was.
▸Plato's Republic asks What is justice?Well documented
The connection
The Republic is built as one long answer. After Thrasymachus says justice serves the strong, and Glaucon asks whether anyone would stay just if invisible, Socrates argues that justice is a harmony in which each part of the city and of the soul does its proper job, and that the just person is the happiest.
When and how
Books I–IV and IX of the Republic, around 375 BC; the challengers are Thrasymachus and Plato's brothers Glaucon and Adeimantus.
How we know
The dialogue's ancient subtitle, 'On Justice', and its structure, question in Book I, answer in Book IV, final defence in Book IX, make the link explicit.
Debates and open questions
Critics since antiquity ask whether Plato changed the subject: inner harmony of the soul may not be what ordinary people mean by treating others justly.
▸Gandhi's satyagraha (nonviolent resistance) gave a nonviolent answer to What is justice?Mostly agreed
The connection
Gandhi held that justice cannot be won by unjust means, because means shape ends. Satyagraha, 'holding to truth', meant openly breaking unjust laws, accepting the punishment, and refusing to hate opponents, aiming to convert them rather than defeat them. The 1930 Salt March against Britain's salt tax is the classic case.
When and how
South Africa from 1906, against laws targeting Indians; India from 1915 to independence in 1947. Martin Luther King Jr. adapted it in the 1950s and 60s.
How sure are we?
Gandhi's own writings, especially Hind Swaraj (1909) and Satyagraha in South Africa, set out the theory; King credited Gandhi's method directly.
Debates and open questions
How much nonviolence, versus war exhaustion, economics and other movements, ended British rule is debated, as is whether it works against ruthless regimes.
▸The veil of ignorance answers What is justice?Well documented
The connection
The veil turns 'What is justice?' into a choice problem: just rules are those you would pick not knowing who you will be. Rawls's answer, equal liberties plus inequalities only when they help the worst-off, stands with Plato's harmony and the utilitarian sum as one of the main answers.
When and how
A Theory of Justice (1971), answering a question Plato's Republic posed around 375 BC.
How we know
It is the most-cited modern answer in political philosophy, and courses and textbooks on justice routinely center on it.
Debates and open questions
Whether a fair procedure guarantees just results, and whether justice can be defined without first agreeing on what a good life is, remain contested.
▸The ethics of care (Gilligan, Noddings) challenged impartial, rule-based answers to What is justice?Mostly agreed
The connection
Gilligan argued that the dominant view treated moral maturity as reasoning about impartial rights and rules, the justice perspective. Care ethicists answered that morality also needs responsiveness to particular people. Susan Moller Okin later added that justice must reach inside the family, where care work is shared unequally.
When and how
Harvard, where Gilligan had worked with Kohlberg; In a Different Voice (1982). Okin's Justice, Gender, and the Family followed in 1989.
How sure are we?
Gilligan's book presents itself as a challenge to justice-based models of moral development, and 'justice versus care' became a named debate in ethics.
Debates and open questions
Whether care and justice are rival frameworks or complementary parts of one morality is debated; many, including Virginia Held, now argue each needs the other.