After all, if all cultures are morally equal, does not cultural relativism both entail and promote tolerance?
We should hope that tolerance does reign in a pluralistic world, but there is no necessary connec- tion between tolerance and cultural relativism. For one thing, cultural relativists cannot consistently advocate tolerance. To advocate tolerance is to advocate an objective moral value. But if tolerance is an objective moral value, then cultural relativism must be false, because it says that there are no objective moral values. So instead of justifying tolerance toward all, cultural relativism actually undercuts universal tolerance. Moreover, according to cultural relativism, intolerance can be justified just as easily as tolerance can. If a culture approves of intolerance, then intolerance is right for that cul- ture. If a culture approves of tolerance, then toler- ance is right for that culture. Cultural relativists are thus committed to the view that intolerance can in fact be justified, and they cannot consistently claim that tolerance is morally right everywhere.
At this point we are left with no good reasons to believe that cultural relativism is true. But the
problems for the doctrine are deeper than that. Like subjective relativism, it has several implica- tions that render it highly implausible.
First, as is the case with subjective relativism, cultural relativism implies moral infallibility. A culture simply cannot be mistaken about a moral issue. If it approves of an action, then that action is morally right, and there is no possibility of error as long as the culture’s approval is genuine. But, of course, cultural infallibility in moral matters is fla- grantly implausible, just as individual infallibility is. At one time or another, cultures have sanc- tioned witch burning, slavery, genocide, racism, rape, human sacrifice, and religious persecution.