What is A Theory of Justice about?

A Theory of Justice, published in 1971, is John Rawls's attempt to construct a systematic alternative to utilitarianism in political philosophy. The book argues that a just society is one whose basic institutions could be chosen by rational agents behind a "veil of ignorance" — a thought experiment in which no one knows their place in society, their class, their natural abilities, or even their conception of the good. Rawls calls this the "original position," and argues that from behind the veil, rational persons would choose two principles: first, that everyone has equal basic liberties; second, that inequalities are only permissible if they are arranged to benefit the least advantaged members of society.

The second principle — the difference principle — is the book's most contested contribution. It doesn't demand strict equality, but it does demand that inequalities be justified from the perspective of those worst off. A society may permit doctors to earn more than custodians, but only if the arrangement, through training incentives and productivity, leaves the least advantaged better off than a more egalitarian alternative would. This is not charity but structural justice: the basic institutions of society are to be arranged according to what those who gain least from them could rationally accept.

Rawls also develops an account of the sense of justice and of what he calls a "well-ordered society" — one in which citizens understand and accept the principles of justice governing their institutions. He engages extensively with Kantian ethics, arguing that his contractualism provides a more plausible framework for impartiality than utilitarian maximization, which can in principle sacrifice individual rights for aggregate welfare.

The book is long, technical, and not written for general audiences. The most practically accessible parts are the original position thought experiment, the two principles and their derivation, and the critique of utilitarianism in Part I. Parts II and III, on institutions and on the concept of goodness, are denser and more contested. The book reshaped political philosophy in ways that are still playing out — virtually every significant work in liberal political philosophy since 1971 has had to engage with Rawls — but it is a demanding text that rewards patient, selective reading.