000ooo000ooo Lyotard

As I understand it, post-modernism is very closely related to modernism except post-modernism encompasses a wider range of objects and time. While modernism relates only to artwork,architecture and other aesthetic endeavors, just about anything can be interpreted through a post-modern view point. As such, questions one might use to explore modernism will be relevant to post-modernism. Lyotard explains one question which he sees as central to the evaluation of modern art: "As Thierry de Duve penetratingly observes,the modern aesthetic question is not 'What is beautiful?' but 'What can be said to be art (and literature?'"
This question illustrates what can be powerfully progressive about post-modern thought both artistically and politically. While I wouldn't say that art has no importance, I also don't think it really has the power to "change the world" or really change much of anything. It may be part of a movement, or it may help one person see a situation in a new light, but a single piece of art will probably have very little impact on the world - regardless of how "powerful" people who wear beret may claim they are. However, in this question of "What is beautiful?" as opposed to "What is art?" lies a host important cultural realizations and appreciations.
"Beautiful" is subjective. Hence, it is cultural. We think something is beautiful because of how it fits into our worldview and what else we've been told is beautiful and how a specific object fits into everything else that has happened in our lives. As such, people from the same or similar cultures will often have similar tastes for beauty. This can be seen throughout history. For centuries though, people failed to realize that beauty truly is subjective. They thought there could be an absolute beauty by which anything that hoped to be beautiful must ascribe. This type of ethnocentrism was at the heart of British imperialism and the European conquest of the "New World". Ethnocentrism is a disease that has plagued humanity for all of its existence. But now, for post-modernism to bring to realization that "What is art?" is a more important question than "What is beautiful?" is highly significant.
If we accept everything on an equal playing field of being "art", we can begin to appreciate things that originally we may have dismissed because they didn't fit the ideals of beauty. It enables us to look deeper into things and give everything a second look. As the cliche goes, "Beauty is only skin deep" and if we only judge things based on whether they fit our immediate presupposition of beauty, we really aren't allowing beauty to be anything beyond skin-deep.