system
Given the following post, respond as if you're commenting on Reddit:
human
What is postmodernism philosophy?

I have done some research but I'm still very confused what it is. Can someone simply explain what post modernism is? 
Thank you.
gpt
The confusion is probably for multiple reasons.  

First, the term itself is impossibly vague.  Post-modernism is a term used to refer to a bunch of artists, philosophers, and other groups doing all sorts of different things with all sorts of different agendas.  There is very little in common for instance between Kurt Vonnegut and Jacques Derrida, and yet they are both "post-modern" in their approach.

Second, many people are confused about what is included in the movement.  Some for instance mistake surrealism, Marxism, or avant-gardism as being part of post-modernism, despite the fact that two of those are entirely modernist movements and Marxism is an example of the kind of political theory that is most often target of post-modernist critique.

Third, the term has been co-opted by the right wing as a pejorative meaning 'art and philosophy we don't like'.  Thus authors who were in fact at the time anti-post-modernism, such as many French Marxists, psychoanalysts, and critical theorists, are now labelled post-modernists when they have nothing in common with someone like Lyotard.

The most canonical statement of what is supposed to draw together this amorphous blob of people is given by Lyotard in *The Postmodern Condition*.  He claims that we have entered a new era, the postmodern era, where it has become difficult for people to take seriously "meta narratives" - stories that are supposed to be all-encompassing descriptions for the way human history progresses, which tend to offer a complete account of moral or political good, and suggest where human progress is headed.  The exact account of what this era entails and what conclusions we ought to draw from entering this new era is where people end up disagreeing.

Marxism is one such metanarrative since according to Marxism, history is the playing out of class conflict, with set stages (at least at some points it seems in Marx's discography, e.g. *The German Ideology*), and while Marxism is neither utopian nor moralistic, a more vulgar version of communism does certainly have some features of that sort.  Liberalism, fascism, and modernism also had metanarratives associated with them (critics of 19th century liberalism give us the term "Whiggish History" which is meant to describe this sort of account of history).  A post-modernist who welcomes this break down of metanarratives would criticize Marxism, liberalism, fascism, modernism, etc because of their commitment to a metanarrative of this sort.

But that's only one statement of what post-modernism entails, certainly the most popular but not the only one.  Since post-modernism refers to a disparate movement, there is very little that we can say about it as a whole, unlike say, Hegelianism.