Identity and family ties
Maybe for some people, explaining who they are begins with a lengthy backstory about the family from which someone hails. Not for Murau. He can barely stand his family. They are somewhat dumpy folks, in his opinion, and they pride themselves in all the wrong was on their Austrian heritage, pretending that their fancy estate makes them fancy, when Murau can tell they're shallow and insipid. He defines himself in contrast to his own family. He goes to Italy, claiming to be exactly the opposite of what they are. When his parents die, he has to reassess this style of self-identification.
Intellectual appreciation
Even apart from his family's perceived philistinism, Murau claims that he has a genuine appreciation of the arts. He feels emotionally and morally stirred by works of genius, and he knows which art is truly genius, and what is derivative, and what is merely entertainment. Part of the reason he resents his family is because they don't even know that there is a deeper kind of art appreciation in life. When Murau goes home to deconstruct his sense of self in light of his parents' death, he reassesses his relationship to art and finds himself at a crisis. Is he faking it so that he can feel morally superior to his folks?
Death and life's meaning
When Murau's parents die, he inherits their beautiful estate. He re-examines his hatred for this home of his, noticing that technically, the reasons he felt embarrassed about his home or misrepresented by it—those reasons are finally put into the grave when his parents die. He sees that he can do whatever he wants, and his emotions, which have guided him for years, are suddenly perplexed and unhelpful. He realizes that his relationship to his parents was wrong, not because he was incorrect, but because in light of human death, the aspects of their character that he regretted were not important at all. Now they are dead, and oblivion has its say. He gets rid of the estate.
