In On the Nature of the Psyche Jung presents a masterly overview of his theories of the unconscious, and its relation to the conscious mind. Jung's discovery of the 'collective unconscious', a psychic inheritance common to all humankind, transformed the understanding of the self and the way we interpret the world. In On the Nature of the Psyche Jung describes this remarkable theory in his own words, and presents a masterly overview of his theories of the unconscious, and its relation to the conscious mind. Also contained in this collection is On Psychic Energy , where Jung defends his interpretation of the libido, a key factor in the breakdown of his relations with Freud. For anyone seeking to understand Jung's insights into the human mind, this volume is essential reading.

Jean-Paul Sartre, the seminal smarty-pants of mid-century thinking, launched the existentialist fleet with the publication of Being and Nothingness in 1943. Though the book is thick, dense, and unfriendly to careless readers, it is indispensable to those interested in the philosophy of consciousness and free will. Some of his arguments are fallacious, others are unclear, but for the most part Sartre's thoughts penetrate deeply into fundamental philosophical territory. Basing his conception of self-consciousness loosely on Heidegger's "being," Sartre proceeds to sharply delineate between conscious actions ("for themselves") and unconscious ("in themselves"). It is a conscious choice, he claims, to live one's life "authentically" and in a unified fashion, or not--this is the fundamental freedom of our lives. Drawing on history and his own rich imagination for examples, Sartre offers compelling supplements to his more formal arguments. The waiter who detaches himself from his job-role sticks in the reader'