Unconscious mind, conceptual artwork. It is estimated that around 10 percent of mental activity is conscious thought, with the remaining 90 percent the unconscious mind. Consciousness is the state of awareness, including subjective feelings and sentience. The unconscious mind includes instinct, dreams, memories, and other mental processes that are automatic and occur without awareness. Other states are semi-consciousness and pre-consciousness. The terms were developed by Sigmund Freud and are used in psychoanalysis. An iceberg metaphor (as here) is sometimes used to express these concepts.