I am an anti-psychiatry fundie - there is no such thing as mental illness and no such thing as madness.
There are no such things as lunatics, nutters, madmen, loonies, headcases, nutters.
Van Gogh, Hitler, Nietzsche, Ezra Pound - none of them were lunatics or madmen because there is no such thing.
Didn't Nietzsche eventually "go mad" in later life?
Well, he may have suffered from a brain disease in later life but he didn't "go mad" because this is meaningless.