I've been reading Scruton's, How to Be a Conservative, both because I find a certain kind of conservative theory interesting and because it's important to read people and ideas with which you don't necessarily agree. In his consideration of multiculturalism ("The Truth in Multiculturalism"), Scruton faults this approach as turning into a kind of cultural relativism. He finds the philosophical grounding of relativism in the perspectivism of Nietzsche and its adoption by "postmodern" thinkers.
Elsewhere, he has praise for some of Nietzsche's thought, but the belief that there are no truths and only perspectives he calls both self-refuting—"What then is this, a truth or not?" he asks—and the basis of our inability to stand up for or against any cultural practice. I think the claim that dear Friedrich has unwittingly contradicted himself is too quick, but what is more interesting to me is a common understanding that Nietzsche is introducing his denial of TRUTH ex nihilo.
This isn't the way he seems to understand himself, nor is it the right way to understand the genesis of his approach. He sees himself as showing the endpoint of philosophy and, most especially, Christianity. To paraphrase: Christ tells us the truth will set us free and, at the end of the day, it sets us free of itself. He's taking things to what he thinks are their logical conclusions. He might be showing his reader the way forward or he might be providing a reductio, but he doesn't think of himself as fully breaking with the tradition he's critiquing.
I don't know whether that full historical path can be fairly traced, but perspectivism and its denial of truth can be seen as having its roots in Kant and his distinction between the phenomenal and noumenal. If that's right—I so rarely am—then we have Hume to blame for awakening Kant from his dogmatic slumbers. Hume's own skeptical project only makes sense in the context of the search for absolute certainty with which René Descartes begins modern philosophy. Descartes—for all his smuggling of philosophical method and terminology—does see himself as a rupture with the philosophy that went before.
So, my point? It's become a commonplace to criticize relativism and postmodernism and to locate their genesis in Nietzsche; but, if you want to find the error, you have to go back further. Once you go down the certainty-seeking skeptical rabbit-hole with Descartes, you're going to end up at either solipsism or perspectivism.
Also, Happy Thanksgiving!