Against utilitarian and empiricist philosophers, Immanuel Kant argued that we must think of ourselves as more than a bundle of preferences and desires. To be free is to be autonomous, and to be autonomous is to be governed by a law I give myself. John Rawls adapted Kant's conception of the autonomous self and drew upon it in theory of justice. Like Kant, Rawls observed that the choices we make often show morally arbitrary contingencies. Someone's choices to work in a sweatshop, for example, might reflect dire economic necessity, not free choice in any meaningful sense. So if we want society to be a voluntary arrangement, we can't base it on actual consent; we should ask instead what principles of justice we would agree to if we set aside our particular interests and advantages, and choose behind a veil of ignorance. Kant's idea of an autonomous will and Rawls's idea of a hypothetical agreement behind a veil of ignorance have this in common: both conceive the moral agent as independent of his or her particular aims and attachments. When we wish the moral law or choose the principles of justice, we do so without reference to the roles and identities that situate us in the world and make us the particular people we are.