From Mark Helprin’s A Soldier of the Great War:

The construction worker nodded. “But of what are you a professor?”
“Aesthetics.”
“What are aesthetics?”
“The study of beauty.”
“Beauty? What for?”
“Beauty. Why not.”
“Why do you have to study it?”
“You don’t. It’s everywhere, in great profusion, and always will be. Were I to cease studying it, it would not go away, if that’s what you mean.”