The reason why we dream is that when we sleep, our brains don't completely stop resting, and some brain cells are still working. Dreaming is a true reflection of physical stimulation and what we see and think during the day. There is a certain objective basis.
Psychologically speaking, dreams are a way to coordinate the balance of human psychological world. People's attention, emotion and cognitive activities will have obvious negative effects if they are accumulated in their hearts. Dreaming can relieve psychological pressure, reduce the burden on the brain and make the brain's thinking work normally.
Physiologically speaking, dreaming can adjust the balance of the body. Dreaming is always accompanied by the whole process of sleep. Some of you have memories, others have no memories, but it can't be said that it doesn't exist every day. Long-term dreamless sleep is bad for your health and you often have nightmares. This is also a sign of physical weakness and some diseases. When the brain is damaged, many body functions can't function normally, and many diseases will appear in our body and mind. Dreaming is the embodiment of the normal operation of the brain and the concrete expression of the balance of the body.
Dream is an objective phenomenon and an indispensable conditional mechanism for the continuation of our lives.