Great art is prophetic and transcends societal values, like a Van Gogh's, that to some extent predicted the spiritual age we are coming into. Conceptual art of the white canvas and lets talk a lot variety, is NOT in that category but probably fits the art for art sakes view. It is not great and history will show that in time our capitalistic technological world produced very little art of lasting value.
I think that capitalism and the rapid growth of technology has bastardized art to the point of no return. Real art is not a trade or craft, which is what capitalism has made it. It is a transcendent quality that even prominent galleries can't often discern, and history will sort it all out. Art has , in the same way religion has, become a trade and not a vocation and as a result, is a non-substantial, void of substance and essence manufactured bit of fluff. If you are selling then you are trying to please the present masses and ergo, not being prophetic in any way. If people don't recognize it they won't buy it.
“In a period of intense suffering, Van Gogh was somehow able to perceive and represent one of the most supremely difficult concepts nature has ever brought before mankind. But more than a masterwork of art, Van Gogh’s painting turns out to hold astounding clues to understanding some of the most mysterious workings of science. Van Gogh and other Impressionists represented light in a different way than their predecessors, seeming to capture its motion, for instance, across sun-dappled waters, or here in star light that twinkles and melts through milky waves of blue night sky."