The veil of ignorance
John Rawls, A Theory of Justice (1971) · also original position, Rawls’s veil of ignorance, justice as fairness
You are to choose the basic rules of a society, but behind a veil that hides who you will be in it. You do not know your class, sex, race, talents, health or even your idea of a good life. Whatever principles you pick, you must then live under them as whoever you turn out to be.
What it tests What principles of justice would people choose for their society if they could not know where in it they would end up?
The case
John Rawls, in A Theory of Justice (1971), asked what principles should govern the basic structure of a society: its constitution, its economy, its main institutions. His method was to imagine a choice made in an “original position”, by people behind a veil of ignorance. Behind the veil you do not know your place in society, your class or social status, your natural talents, your race or sex, or even your conception of what makes a life good. You do know general facts about how societies and economies work. You must choose principles that you will then live under.
Why the veil
The point of the veil is fairness. In real life, people arguing about justice tend to favour rules that favour themselves: the talented prize talent, the wealthy defend property. Behind the veil nobody can do that, because nobody knows which rules would favour them. Whatever they agree to under those conditions is, Rawls argued, fair to everyone.
What Rawls thought we would choose
Rawls argued that people in the original position would choose two principles, in order of priority:
- Equal basic liberties. Each person has an equal right to the most extensive scheme of basic liberties compatible with the same for all: freedom of speech, conscience, association, the vote, the rule of law.
- Fair inequality. Social and economic inequalities are permitted only if they are attached to positions open to all under fair equality of opportunity, and if they benefit the least advantaged. The second condition is the difference principle.
His argument appealed to a cautious rule of choice, maximin: when the stakes are your whole life prospects and you cannot assign probabilities, choose the option whose worst outcome is best.
The objections
Why not maximise the average? The economist John Harsanyi argued that rational people behind the veil would assign equal chances to every position and maximise expected well-being, which leads to utilitarianism, not to the difference principle. Much depends on whether the maximin rule is rational there.
Justice is historical. Robert Nozick, also the author of the experience machine, argued that a just distribution is whatever results from just acquisitions and voluntary transfers, not one that fits a pattern chosen in advance.
Who is choosing? Communitarians such as Michael Sandel argued that people stripped of their ends, attachments and identities are not intelligible agents, so their choices cannot ground principles for real people.
The veil and AI
The veil has become a practical test in the ethics of automated decisions. Would you accept the rules a system uses to approve loans, allocate welfare or flag fraud if you did not know whether you would be the applicant it approves or the one it rejects? The test is especially pointed for systems that determine people’s standing, such as identity and welfare infrastructure, which is the subject of What does an institution owe the people whose standing it produces? and Can consent make Aadhaar legitimate?
Terms
Questions people ask
What is the veil of ignorance?
It is a device from John Rawls’s A Theory of Justice (1971). To find fair principles for a society, imagine choosing them without knowing your own position in it: your class, race, sex, talents or beliefs. Since you cannot tailor the rules to your own advantage, the principles you would choose are fair to everyone.
What principles did Rawls think people would choose behind the veil?
Two. First, equal basic liberties for everyone. Second, social and economic inequalities are allowed only if positions are open to all under fair equality of opportunity, and if the inequalities benefit the least advantaged members of society, which Rawls called the difference principle.
What is an example of the veil of ignorance?
Suppose you must decide whether a society should provide public healthcare without knowing whether you will be born healthy and wealthy or chronically ill and poor. Rawls argued that, facing that uncertainty about something so important, you would choose rules that protect the person who ends up worst off.
What are the criticisms of the veil of ignorance?
John Harsanyi argued that rational choosers would maximise expected well-being, which supports utilitarianism rather than Rawls’s principles. Robert Nozick objected that justice concerns how holdings came about, not patterns of distribution. Communitarians argued that people stripped of all their commitments are not recognisable choosers at all.
How is the veil of ignorance used in AI ethics?
It is used as a test for the fairness of automated systems: would you accept the rules an algorithm applies to decide loans, benefits or bail if you did not know which side of its decisions you would be on? Researchers have also tested whether people reason about AI alignment principles more fairly when placed behind a veil.
Sources and further reading
- Rawls, J. (1971). A Theory of Justice. Cambridge, MA: Harvard University Press.
- Harsanyi, J. C. (1975). Can the maximin principle serve as a basis for morality? American Political Science Review 69(2): 594–606.doi.org/10.2307/1959090
- Nozick, R. (1974). Anarchy, State, and Utopia. New York: Basic Books, chapter 7.
- Weidinger, L. et al. (2023). Using the veil of ignorance to align AI systems with principles of justice. Proceedings of the National Academy of Sciences 120(18).doi.org/10.1073/pnas.2213709120
- Original Position, Samuel Freemanplato.stanford.edu/entries/original-position/
- John Rawlsplato.stanford.edu/entries/rawls/