"POSTmodernISM is often a B.S. talking point used as a feeble attempt by most people to seem like they are contemporary.
The "ism" makes it more BS than the silly "post" moniker, particularly if you are looking at a Derrida based deconstruction (he has said over and over that if his "deconstruction" ever became "deconstructionISM" then it would not be his intent or even nearly the same thing he has been talking about)
Check out Derrida, Lyotard, Nietzche, and pre Tibetan Buddhism (or preferably Taoist texts) and filter the contemporary rhetoric through those lenses.
A large concept is the idea that grand narratives are either not inclusive enough to explain everything, or simply human constructions that can't explain everything. Thus we are left with pluralism. But, the human tendency to want to explain everything in a neat package keeps rearing it's ugly head and people either make up more grand narratives to try to explain everything, or get frustrated and think that everything is nothing.
In my opinion, both extremes are foolish endeavors, motivated by desire, and as separate as the republican/democrat two-party political system we have here in the U.S. (two different parties,but still really the same shit)
Often, a misunderstanding of deconstruction and "post" modern is the same misunderstanding of both nihilism and buddism. The point is NOT to come to some sad realization that everything is a construct, thus a lie. It is to recognize that we (humans) construct our realities without awareness. A recognition of these constructions can be found (if you believe Derrida) through deconstructing them piece by piece, within each paradigms' own rules. A similar result can be found through the neo-Buddhist writing of Nietzche, particularly in his recognition of the "will to power", in so much as he is pointing out that we are creating our own realities. It's not magic. It's just awakening. Enlightenment is not a magical, physical thing. it's simply an awakening through awareness.
"postmodernism" has been a phrase used for a long time now and is, itself, full of smoke and mirrors. Explore every question for yourself. it's the only way to grow beyond catch phrases and popular distraction."