Veil of Ignorance

The veil of ignorance is the central device of John Rawls's A Theory of Justice (1971). Rawls asks the reader to imagine rational agents choosing the basic principles of their political society from behind a veil that screens out information about who they will turn out to be — their class, race, gender, talents, conception of the good, or generation.

Behind the veil, no agent can choose principles that favor his own particular position, because he does not know what that position will be. Rawls argues that rational agents in this original position would converge on two principles: equal basic liberties for all, and inequalities permitted only when they benefit the least well-off. The device gives a rigorous structure to the intuition that fairness is impartiality — though critics from Nozick to Sandel have argued that it imports substantive assumptions Rawls denied or smuggles a controversial conception of the person into the framework.

Rawls argues that two principles emerge from rational choice behind the veil. The first principle gives each person an equal claim to a fully adequate scheme of basic liberties. The second principle — the difference principle — permits inequalities only when they benefit the least well-off members of society. The argument turns on the maximin reasoning Rawls attributes to rational agents who must choose without knowing their own position.

The device has been the most criticized element of Rawls's framework. Nozick argued that the veil already presupposes a controversial conception of the person as separable from her natural endowments, and that historical entitlements escape the framework altogether. Sandel charged that the veiled chooser is metaphysically too thin to choose anything substantive. Habermas argued that hypothetical agreement is no substitute for actual democratic deliberation. Defenders including Thomas Pogge and Samuel Freeman have refined the device against each line of objection.