Criticizing Postmodernism
Be warned. This post uses the coarse "BS" word but it is only in quoting. Sorry.
I saw this review for a book by Harry G. Frankfurt (a Princeton philosophy professor emeritus). This is from the Amazon.com's own summary of a book titled On Bullshit:

Bulls**tting, as he notes, is not exactly lying, and bulls**t remains bulls**t whether it's true or false. The difference lies in the bulls**tter's complete disregard for whether what he's saying corresponds to facts in the physical world: he "does not reject the authority of the truth, as the liar does, and oppose himself to it. He pays no attention to it at all. By virtue of this, bullsh*t is a greater enemy of the truth than lies are."
...
...he points to one source of bulls**t's unprecedented expansion in recent years, the postmodern skepticism of objective truth in favor of sincerity, or as he defines it, staying true to subjective experience. But what makes us think that anything in our nature is more stable or inherent than what lies outside it? Thus, Frankfurt concludes, with an observation as tiny and perfect as the rest of this exquisite book, "sincerity itself is bulls**t."

A viable criticism on postmodernism: nonsense out of complete disregard for objective truth. (I added the astericks in the quote)