Summarizing your arguments: 1) The dictionary gives...
It is impossible to define art
Summarizing your arguments: 1) The dictionary gives "manifestation" as a synonym for "expression," and "manifestation" implies that something must be revealed. But art is art regardless of whether or not it is seen/appreciated by others. 2) Art can't be defined because people will disagree. My responses: 1) I agree that art doesn't need to be shown to others in order to be considered art. Expression can be private. If I paint a painting then lock it in a safe without ever showing it to anyone else, are you saying the painting would cease to be expressive? That's just silly. When a person writes in a private diary, isn't that expression? 2) As I said before, I don't expect this debate.org page to spawn a global art revolution that will accept my definition as gospel, but I do think it's a pretty good definition. I have to disagree with your assertion that my definition doesn't apply well to certain forms of art. Consider: the central drive of every person who purports to create art is to convey thoughts, sensations and/or emotions. The way I see it, that's basically the definition of expression.