The main difference between humans and animals is that humans can think abstractly, make plans and imagine the future. These abilities are the facets of our consciousness, and people have tried to study consciousness at all times.
Consciousness is a reflection of reality in the human psyche. It includes thoughts, imagination, self-awareness, perception of information, and so on, and is purely individual. That is, what you see, imagine and think is only your subjective experiences, for the rest, the picture of the world may well differ.
In primitive times, people were interested not in consciousness, but rather in its altered state. That is why shamans, who could enter and be in an altered state of consciousness, aroused special respect. These are considered trance and ecstasy. Shamans heard voices and experienced hallucinations, and primitive society considered them to be healers, psychologists, and prophets.
To enter an altered state of consciousness, shamans used various psychotechnics, as well as hallucinogenic substances of natural origin, such as mushrooms. Paradoxically, they really could heal some diseases, foresee the future, and talk to the spirits of the dead.
In the Middle Ages, philosophers dealt with issues of the psyche and consciousness. Psychology and mysticism were closely intertwined. People believed that consciousness is a divine spark, each person is able to predict the future. Particular attention was paid to the interpretation of dreams - all dreams were considered prophetic.
In the period from the 18th to the 12th century, psychotherapists were occupied with all the same topics of changing consciousness, especially hypnosis and somnambulism. They asked questions - why after hypnosis the patient does not remember what happened to him during hypnosis, and how in a state of somnambulism a person can move, speak, perform any actions. However, the answers to these questions lie more in the field of physiology. Along the way, such phenomena as clairvoyance, a state of passion, amnesia, and exacerbation of feelings were identified. Psychologists with special interest investigated multiple personality disorder, and also concluded that even those memories that seem to be forever erased from our memory still live somewhere in the depths of the subconscious, and they can be pulled out using hypnosis. And here it would be reasonable to recall the notorious Sigmund Freud.
In the twentieth century, with the development of his theory of psychoanalysis, consciousness received a reverse side - the unconscious. The unconscious manifests itself in dreams, automatic actions, reservations. The unconscious protects our brain from constant tension of consciousness, displaces unpleasant memories and experiences. The unconscious also keeps all our secret desires and needs, when they cannot be satisfied for any reason.
