The aims of art

In one of his essays, George Orwell says "All art is propaganda." Even reading that as a kid, I thought "Well I'm not so sure about that, old horse." Art has been hijacked for utilitarian aims, particularly political aims, but it was not always so. You might say, well, all that old stuff is just propaganda for a religious worldview. But those cathedrals took a long time to build, and the scaffolding was not always so secure. You can call the Pieta propaganda, but if you compare it to 20th century art, it comes out looking pretty good. 

Propaganda can reach masterpiece levels, I guess the examples that come to mind are Richard III and The Shining, which is the only horror film I enjoyed (to me they're all horror films). But who knows what the verdict will be two centuries after its creation? The best art has the force of truth in it, this is even and especially the case with comedy, which is topical and dated by its very nature.