I've noticed, in a few comments on different posts, that some readers are attracted to views that reject the existence of objectivity.  Roughly speaking, something is objectively true if its truth does not depend on any particular person as knower or any particular group as knowers.  Put differently, if proposition P is objectively true, it is true for everyone, everywhere; any rational person should be able to rationally assent to P.   Many instinctively think “well, too bad, everything (or everything about moral and politcial life) is relative; there is no absolute or universal truth.”  Indeed, there is a popular—but poor—argument in contemporary (Western) culture that takes this belief in a lack of objectivity as its premise for an important conclusion.  The argument is deceptively simple: as everything is relative, we should not impose our views, so should tolerate.  This argument takes a variety of forms depending on the sort of relativism being espoused.  On one version, knowledge is thought to be relative to individual knowers.*  Call this subjectivism.  The subjectivist believes that what is true for him is not necessarily true for you.  According to cultural relativism, knowledge is indexed to cultures so that what is true for one culture is not necessarily true for another culture.  Given that there is nothing that is universally true, the idea goes, we can’t insist on our own view and so should tolerate.  As popular as this argument is, it is simply misguided.  Consider the simple fact that if everything is relative, the idea that “we should tolerate” is also relative.  This means that on the subjectivist view, if I believe it to be true, its true for me and I should tolerate but if you don’t, you shouldn’t.  Or, on the cultural variant: if my culture believes we should tolerate, we should, but if yours doesn’t, it shouldn’t.  Not exactly a helpful defense of toleration.  Indeed, why this argument is as popular as it is, is unclear (I have some ideas).  Why would one believe that we should not impose our views if there is no (universal) truth about not imposing views?

Here's the thing: I do value toleration.  Indeed, I would say it is the core of my libertarian beliefs, the fundamental political value I hold to.  Because I value it, I want to be able to defend it.  I want arguments that are rationally persuasive to all rational parties.  I think there are such arguments (many, actually).  None of them start with relativism.

*One point of clarificaton: that something is of a subject does not mean it is subjective in the sense that I am discussing here.  Only subjects can be in pain, for example, but I take it that whether a particular subject is in pain or not is an objective fact.   Someone either is in pain or not.  They might be lying about being in pain, of course, but if they genuinely believe themselves to be in pain, I take it they are objectively in pain.