Toleration is a paradoxical political virtue. To tolerate the morally odious smacks of moral weakness. Yet to speak of toleration in the case of beliefs or practices that are morally acceptable also seems to speak poorly of the individual or group that practices toleration. To tolerate is to prescind from using the power one has to condemn or prohibit a practice of which one disapproves. But if the practice being tolerated is morally acceptable, then on the face of it there is no reason to disapprove of it in the first place. Thus the paradox: a political virtue that has been widely praised throughout history ends up being difficult to spell out without making the tolerators either morally spineless or overly censorious.

Rawls’s forays into the discussion of toleration begin with the first of these two apparently unattractive postures. The question he asks, in an early essay on “Constitutional Liberty and the Concept of Justice,” and then again in A Theory of Justice, is whether “tolerant sects” have the right to suppress “intolerant sects,” where intolerance is defined as the rejection of the principle of equal liberty. Rawls argues that they do not. In his view, the widely held thought that the intolerant can be suppressed stems from a fallacious inference. Though it is true, Rawls claims, that the intolerant do not have a legitimate claim against those that would suppress them, it does not follow that the tolerant have the right to suppress them. Whether that right exists should be determined on the basis of principles of justice, rather than on the presence or absence of a legitimate claim on the part of the intolerant that they not be suppressed.