On the forty-second page of “Law, Legislation and Liberty, Volume 2: The Mirage of Social Justice” author F. A. Hayek wrote (emphasis added):
this does not exclude the possibility that we may later discover cases to which, if we had not commited ourselves, we should wish not to apply the rule, and where we discover that we had thought to be quite just is in fact not so; in which event we may be forced to alter the rule for the future. Such a demonstration of a conflict between the intuitive feeling of justice and rules we wish also to preserve may often force us to review our opinion.
We shall later have to consider further the changes in the recognized rules which will be necessary for the preservation of the overall order if the rules of just conduct are to be the same for all. We shall then see that often effects which seem unjust to us may still be just in the sense that they are necessary consequences of the just actions of all concerned. In the abstract order in which we live and to which we owe most of the advantages of civilization, it must thus in the last resort be our intellect and not intuitive perception of what is good which must guide us. Our present moral views undoubtedly still contain layers of strata deriving from earlier phases of the evolution of human societies—the small horde to the organized tribe, the still larger groups of clans and the other successive steps toward the Great Society. And though some of the rules or opinions emerging in later stages may actually presuppose the continued acceptance of earlier ones, other new elements may be in conflict with some of those of earlier origins which still persist.
The significant of the negative character of the test of injustice
The fact that, though we have no positive criteria of justice, we do have negative criteria which show us what is unjust, is very important in several respects. It means, in the first instance, that, though the striving to eliminate the unjust will not be a sufficient foundation for building up a wholly new system of law, it can be an adequate guide for developing an existing body of law with the aim of making it more just. In such an effort towards the development of a body of rules, most of which are accepted by the members of society, there will therefore also exist an 'objective' (in the sense of being inter-personally valid, but not of universal—because it will be valid only for those other members of the society who accept most of its other rules) test of what is unjust. Such a test of injustice may be sufficient to tell us in what direction we must develop an established system of law, though it would be insufficient to enable us to construct a wholly new system of law.