A tangential question for those in the know, but first let me preface it.
I can't claim that post modernist are full of themselves because philosophy is not my gig...they do sound like they are full of it though. From my perspective (wow! I am becoming a postmodernist already), starting with the Pre-Socratic philosophers all the way to 19th century philosophers, we can safely say that they have influenced practically every aspect of modern western society: Ethics, Science, Art, Politics, Forms of Government, etc, etc.
What do the 20th century philosophical schools have done to improve our world or our understanding of it? Will they matter in the future?