Well, that gets us near aesthetic philosophy -- something is beautiful if most relevant people will or should find it beautiful. The distinction between "will"

Well, that gets us near aesthetic philosophy -- something is beautiful if most relevant people will or should find it beautiful. The distinction between "will" and "should" can of course cause issues, and in this case "relevant people" can be troublesome as well. But as a shorthand, "This is a beautiful theory" is a lot like "This is a theory that seems like it SHOULD -- or at least COULD -- be right".