the physician who pioneered the study of the human subconscious was
History of hypnosis From the 1880s the examination of hypnosis passed from surgical doctors to mental health professionals. Charcot had led the way and his study was continued by his pupil, Pierre Janet. Janet described the theory of dissociation, the splitting of mental aspects under hypnosis (or hysteria) so skills and memory could be made inaccessible or recovered. Janet provoked interest in the subconscious and laid the framework for reintegration therapy for dissociated personalities.
Philosophy of mind In Western Philosophy, the earliest discussions of dualist ideas are in the writings of Plato who maintained that humans' "intelligence" (a faculty of the mind or soul) could not be identified with, or explained in terms of, their physical body.[6][30] However, the best-known version of dualism is due to René Descartes (1641), and holds that the mind is a non-extended, non-physical substance, a "res cogitans".[7] Descartes was the first to clearly identify the mind with consciousness and self-awareness, and to distinguish this from the brain, which was the seat of intelligence. He was therefore the first to formulate the mind–body problem in the form in which it still exists today.[7]