Instead of thus employing the libido in the real world, however, certain people never relinquish the seeking for satisfaction in the shadowy world of phantasy and even though they make certain attempts at adaptation they are halted and discouraged by every difficulty and obstacle in the path of life and are easily pulled back into their inner psychic world. This condition is called a state of introversion. It is concerned with the past and the reminiscences which belong thereto. Situations
Jung, C. G.. Psychology of the Unconscious (Kindle Locations 300-303). Dover Publications. Kindle Edition.