General Psychological Theory: Papers on Metapsychology (The Collected Papers of Sigmund Freud): Sigmund Freud: 9781416573593: Amazon.com: Books. General Psychological Theory: Papers on Metapsychology (The Collected Papers of Sigmund Freud) [Sigmund Freud] on Amazon.com. *FREE* shipping on qualifying offers. In fifteen essays, sigmund freud explains his most controversial theories exposing the darkest corners of the human psyche. Best known for his research into the unconscious mind www.amazon.com