In “The Relations between the Ego and the Unconscious” I had discussed only my preoccupation with the unconscious, and something of the nature of that preoccupation, but had not yet said anything much about the unconscious itself. As I worked with my fantasies, I became aware that the unconscious undergoes or produces change.
Only after I had familiarized myself with alchemy did I realize that the unconscious is a process, and that the psyche is transformed or developed by the relationship of the ego to the contents of the unconscious.
In individual cases that transformation can be read from dreams and fantasies.
In collective life it has left its deposit principally in the various religious systems and their changing symbols.
Through the study of these collective transformation processes and through understanding of alchemical symbolism I arrived at the central concept of my psychology: the process of individuation. ~Carl Jung; Memories, Dreams and Reflections, Page 209.