There are many books with unreliable narrators under the control of sane authors; this is the only one I know where a sane, reliable narrator (on the book’s own terms) is under the control of a clearly crazy author.
The hysteria suited him. He seems to have been a man of intellectual passion and compulsive appetite (he was married five times), the kind of guy who can’t drink one cup of coffee without drinking six, and then stays up all night to tell you what Schopenhauer really said and how it affects your understanding of Hitchcock and what that had to do with Christopher Marlowe.
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The vision of an unending struggle between a humanity longing for a fuller love it always senses but can’t quite see, and a deranged cult of violence eternally presenting itself as necessary and real—this thought today does not seem exactly crazy. The empire never ends.