The commitment to ‘social justice’ has in fact become the chief outlet for moral emotion, the distinguishing attribute of the good man, and the recognized sign of the possession of a moral conscience. Though people may occasionally be perplexed to say which of its conflicting claims advanced in its name are valid, scarcely anyone doubts that the expression has a definite meaning, describes a high ideal, and points to grave defects of the existing social order which urgently call for correction. Even though until recently one would have vainly sought in the extensive literature for an intelligible definition of the term, there still seems to exist little doubt, either among ordinary people or among the learned, that the expression has a definite and well understood sense.
But the near-universal acceptance of a belief does not prove that it is valid or even meaningful any more than the general belief in witches or ghosts proved the validity of these concepts.
Friedrich A. Hayek, The Mirage of Social Justice, being the second volume of Law, Legislation and Liberty (University of Chicago Press, 1976), p. 66.