In 1909 Jung resigned from Burgholzli Hospital to focus on research into mythology. "I went about with all these fantastic figures: centaurs, nymphs, satyrs, gods and goddesses, as though they were patients and I was analyzing them." The result: Transformations and Symbols of the Libido. There are two types of thinking directed and fantasy,
Fantasy thinking was passive, associative, and imagistic and exemplifies mythology. With comparative studies of myths he discovered typical myths or primoral images. Example: the hero. These images were to be found in a layer of the unconscious - later identified as a collective unconscious.
In 1952 Jung identified this work as the beginning of the second half of his life. The studies made him realize that his life lacked myth; his self-experimentation was a way to discover the myths of his life.