The problem is that the position is logically incoherent being self-undermining. If all truths are relative, then so is postmodernism. There is no more objective reason to accept it than anything else. While the postmodernist would initially be pleased with this, it shows that they can mount no criticism against conservativism, which is true according to its own standard of truth, which is objective. But, if the postmodernist grants the relative truth of conservativism, then it follows that by the conservative criterion of truth, conservativism is objectively true! Thus, relativism is objectively false and can be rejected!
https://www.quora.com/What-are-the-problems-with-postmodernism
Postmodernism is an intellectual dead end; it’s central premise seems to be derived from a saying of Nietzsche’s, “There are no facts; only interpretations”, which is thought to mean that each one of us views “reality” through our individual perspective. This is true to a degree, but as with so many aphorisms, there are limits to its validity; let’s say person x thinks a temperature of 20 C is a warm day; that is a fact for person x. Person y finds 20 C to be cool; a fact for person y. Both, however, would agree that 60 C is too hot, since that would be close to a record breaking high temperature on earth. We have some wiggle room for debate, but beyond a certain point, we have to acknowledge that there are actually facts upon which we can agree.
Postmodernism seeks to deny the existence of unbiased truth, and claims that all interpretations, particularly of a text, are equally “valid”; In “The Ship of Fools”, Michele Foucault attempts to argue that mental illness is not something that can be defined outside of a dominant cultural paradigm of what is considered to be sanity. There is a degree of truth to this, but as postmodernists tend to do, he carries the point too far; followed to its logical conclusion, a “madman’s” conviction that he is Napoleon Bonaparte is just as valid as a “sane man’s” conviction that he is not. The madman is not, in fact, “mad”; he’s just “different”.
Since postmodernism promotes a highly subjective epistemology, it concludes that what is promoted in society as objective truth is actually nothing of the sort, but rather a subjective view of reality that is imposed through power. Yet again, there is a degree of truth to this; in communist countries, the “truth” of the Marxist-Leninist sociopolitical model was imposed by a dictatorial one party state, and on occasion, dissenters were sent to psychiatric hospitals, since the denial of this “truth” was, at least, treated as evidence of insanity; Foucault was half right. On the other hand, Soviet Russia clearly had a grasp of objective reality when it came to physics and engineering, being the first nation to put a satellite into orbit; they were smart enough to keep the professional ideologists out of their laboratories.
By insisting that a given text has an infinite number of interpretations, postmodern philosophy is effectively saying that texts have no inherent meaning; the obvious retort to this foolishness is to say “Why, then, should we bother reading postmodernist texts? If they can mean anything, they mean nothing.” If you have read any postmodernist texts, they are, in fact, devoid of meaning, other than the constant assertion of a rather sophomoric skepticism, couched in a deliberately obfuscatory dialect of academese; try reading anything by Judith Butler, and you’ll see what I mean. …
Postmodernism is also the underlying philosophy of Wokeism; for the Woke, biology, and science in general, is merely a “social construct” imposed by the cis-het white male patriarchy to maintain its dominance; “Other ways of knowing”, such as “indigenous” creation myths, are just as “valid” as any of the scientific theories advanced by dead white men, and should be taught as such to schoolchildren. A biological male can become a woman merely by “identifying as” such, and once the claim has been made, only a “transphobic bigot” would question that claim. In an eerie echo of Soviet ideological authoritarianism, female swimmers who objected to the presence of the male-bodied, but female identifying swimmer, Lia Thomas, in their changing rooms, were referred for “psychological counselling”. They “thought” they saw a man, and made the mistake of believing their “lying eyes”, as opposed to submitting to Woke gaslighting.
I am Philailouros Semisapiens, unworthy prophet of le Dieu-Chat, the French Feline Creator of the universe. We humans are the result of an unfortunate experiment to create a species of intelligent biped, which His Felinity was persuaded to undertake by the wicked Lucy Fur. His Felinity took a catnap that spanned several eons during the course of this experiment, and the bipeds continued to evolve in an unguided manner until we reached our current form, at which point His Felinity woke up, and realized what a mistake it had been to succumb to Lucy Fur’s persuasion, since a whole planet had been overrun by a species of narcissistic primate. In His mercy and wisdom, le Dieu-Chat sent us his little avatars to guide us in the path of Felinity, and to remind us that bipedalism is, at best, sub par.
For the Woke postmodernists, my account of creation and evolution is just as “valid” as anything that was imagined by dolts like Einstein and Darwin; it is “my truth”, and “my lived experience” that cats are the superior species.
The problem with postmodernism is that it induces a form of madness by denying the existence of a hierarchy of interpretations, when in reality, such hierarchies do exist: Einstein’s interpretation of the laws of physics is better than Newton’s, since it allows us to make more accurate predictions; Darwin’s conception of evolution is better than Lamarck’s, since it is actually in accordance with what we observe in nature; someone born with a female phenotype has a better claim of being a woman than someone born with a male phenotype…
Postmodernism, in its various forms, has metastasized from being a type of intellectual … engaged in by French “philosophers” to become dangerously prevalent in politics, academia, education, science, and even the practice of medicine in the form of “gender affirming care” practiced upon confused children. Anyone can be a postmodernist, since this epistemological onanism requires no evidence or intellectual rigor; all you need to do is “make sh** up”, repeat it loudly and often, and claim to be “offended” when people disagree with you.
If we surrender to the radical subjectivism and solipsism of postmodernism, we will lose the ability to communicate with each other; if logic itself is regarded as merely “a tool of the patriarchy”, and words like “woman” and “racism” can be arbitrarily redefined for ideological reasons, an argument from one ideological position will cease to be comprehensible to those who hold a different position; this is already happening; those with competing ideologies increasingly talk at, or past each other. How can we simultaneously support women’s rights, and promote the idea than any male can become a woman, merely by identifying as one? The answer is, we can’t, and we have the epistemological chaos generated by postmodernism to “thank” for the fact that we even have to try.
In the end, postmodernism is a form of ressentiment, manifested by intellectual mediocrities against the rationalism and empiricism of the Enlightenment; being unable to generate any new ideas, windbags like Derrida and Foucault merely sought to deconstruct the powerful ideas that underlie Western thought, and attempt to sound profound in the process. Let’s hope that we can move beyond this incoherent, sloppy, and destructive mode of thinking, which merely serves to enrichen its grifting practitioners, while the rest of us pay the price.”