Despite all the subjectivity, the differences in taste, the contradictory philosophies, and the difficulty in translating aesthetic concepts to different artistic mediums, there is one thing that I've become pretty sure of. It's simple, but it probably had to be (again: I do not think I am good at aesthetics). It's not terribly original, but it's what I've got, so here it is.
A work of art is not finished until it is received.
It's the audience that finishes a play. The viewer that finishes a painting. The listener who finishes music. A work of art is not finished until someone takes it in. The final collaborator. That's why theatre isn't theatre if there is no audience. It's why the same painting can mean such different things to different people. It's why we have to talk about subjective vs. objective. In math, there is no subjective, because the numbers add up whether or not anybody's there to add them. In art, though, there is. Because a work of art is an unfinished thing, waiting for someone to come along and complete it.
It's tempting to get mad at someone for not liking the things I like. But how can I? They're not me. They can only finish works of art their way, just as I can only finish them in mine. And I can't be too dismissive of what other people love that I don't, just because I couldn't finish it the way they did.
This seems more out of left field than usual for me (is there a usual yet? Can i say that?), but I felt it needed to be said. I needed to say it. So that if I disagree with myself in ten years, I can remind myself what a twit I used to be. At any rate, it's all I can do. The rest is up to you.