One of my favorite C.G.Jung excerpts from his book: Memories, Dreams, Reflections: I was greatly intrigued by the fact that a woman should interfere with me from within. My conclusion was that she must be the “soul,” in the primitive sense, and I began to speculate on the reasons why the name “anima” was given to the soul. Why was it thought of as feminine? Later I came to see that this inner feminine figure plays a typical, or archetypal, role in the unconscious of a man, and I called her the “anima.” The corresponding figure to the unconscious of woman I called the “animus.”
This was the beginning of Jung’s Depth Psychology, the understanding of part of the contents of our unconscious state called “archetypes.”