In liberalism the relation between one self and another is contingent, not constitutive; and it is law which enables the freedom of separate selves to co-exist. As expressed in Rawls’s first principle of justice, this means that ‘each person has an equal right to the most extensive equal basic liberties compatible with a similar system of liberty for all’. So that, as he puts it, ‘liberty can be restricted only for the sake of liberty itself’ (Rawls, 1972: 244).