The origin of dreams: during sleep, brain cells are basically in a static state, and only a few are still weak and active to a certain extent. Because this activity is basically unaffected by perception and not controlled by rational thinking, it has formed the characteristics of strong imagery and weak logic of dreams. If the activity of these brain cells is too weak or slack, dreams cannot be formed. However, when there is some abnormality in the body, the number of brain cells at rest during sleep decreases, and there are many disturbances from waking factors. At this time, the relationship between the dream formed and the state of mind when awake has increased, which is what people often say, "thinking day and night." For the first time, the interpretation of dreams tells those ignorant and full of doubts that dreams are a real dialogue between a person and his own heart, a process of learning from himself, and another life closely related to himself. Everything you see and feel in secret dreams, breathing, tears, pain and happiness is not meaningless. Freud pointed out that any dream can be divided into manifestation and concealment: manifestation, the surface of the dream, refers to those things that people can remember and describe, that is, similar to masks; Invisible refers to the essential content of dreams, that is, the real meaning, similar to the real desire covered by masks.