The argument of this paper, which is conducted at two distinct levels of abstraction, has four parts. First, I consider how the disputed character of the concept of freedom bears on the definition of liberalism. This will be done by examining the contrasting accounts of the concept of freedom advanced by Felix Oppenheim and Sir Isaiah Berlin: my conclusion is that the contestability of the concept of freedom does not constitute an insuperable obstacle to formulating a working definition of liberalism. Secondly, I consider the general thesis that some, if not all, of the central concepts of social and political thought have an essentially contestable character, and look in particular at the application of this thesis to the concept of the ‘political’. Thirdly, I consider some aspects of the theories of distributive justice advanced by John Rawls and Robert Nozick, concluding that the supposedly contractarian mode of argument adopted by each of these writers is insufficient to yield the distributive principles specified, which must rather rest upon definite normative commitments and quasi-empirical assumptions about man and society. Fourthly, I explore the prospects of a procedural approach to questions of distributive justice, and I claim for such an approach a special congruence with basic liberal principles regarding equality and freedom. The substantive result of these arguments is that, within the conceptual framework of the liberal tradition, a just distribution is any that emerges from background economic and political institutions protecting equal freedom. The methodological or metatheoretical result is that, in virtue of the contestability and indeterminacy of the constitutive concepts and regulative principles of political discourse, my arguments fail to be demonstrative, having a persuasive and dialectical rather than a deductive form. If my arguments can be sustained, these are features of the paper it shares with every other essay in social philosophy.