Abstract
Legal philosophy must be based on a set of substantive political values about such fundamental matters as the nature of the political community and the meaning of human freedom. This general thesis is illustrated by the analysis of moral discourse about the justification and limits of liberty-rights and equality-rights.The most effective way of arguing about the liberal conception of individual liberties (consistent with the Millian Harm Principle) is by recourse to the priority of the right over the good. But this conception is little more than a restatement of the Harm Principle itself hence, a more fundamental justification for it is required. This can be provided by a substantive conception of equality of individuals as moral agents who are capable of choosing, pursuing and changing their own conceptions of the good, within the parameters of avoiding harm to others.