If, after all I've shared this past week about the obvious problems with moral relativism, you still have some inclination toward that view, it's likely because you believe that tolerance is a worthy goal. It is, after all, a virtue that's riding an all-time high; indeed, for some (including, especially, moral relativists) tolerance is the 'boom shiggety,' the highest of all virtues.
I'll save it for another post to discuss how tolerance is misunderstood in today's culture. But for now, let's grant (and that willingly, since I believe it) that there exists a virtue known as tolerance and that people should exhibit this virtue in their dealings with others.
Here again we run into a huge problem for the moral relativist. Because while I--as a moral objectivist--can say that people should be tolerant--the relativist cannot. Words like 'should' and 'ought' are terms of moral obligation, and moral obligation is exactly what relativists deny. If there are no objective moral absolutes--as the relativist claims--then tolerance is not one either. Put another way, if every individual has the right to make up his own ethical principles, then there is no way of judging or blaming the individual who chooses to make intolerance the core of his morality.
You see, one cannot make a case for moral relativism on the basis of tolerance, nor can one make the case for tolerance from a position of moral relativism.
If tolerance is a virtue, then moral objectivism must be true.