In other words, they deny the existence of rational standards by which to determine whether the beliefs and goals of one individual, group, or nation are more valid or intrinsically superior to those of another.
Cynicism is rampant.
Morality, religion, metaphysics, all the rest of ideology and their corresponding forms of consciousness, thus no longer retain the semblance of independence. Another perverse mind, exempting itself from its own conclusions. Amazing how many academic earthlings have made a livelihood teaching this sophisticated madness. Thus the slightest restriction on, let's say, the presumption of innocence of the accused is said to demonstrate the absence of the rule of law. The slightest failure of an electoral system demonstrates contempt for political equality.