The second question: wake up in the morning and feel back in another world. A: Dreams are really different from the real world. Dreams are the product of splicing information parts in the knowledge structure of individual brains. The real world is the result of external environment stimulation on human brain nervous system. If individuals regard dreams as real, or notice that the dream world is really different from the real world, then this feeling will lead to your doubt. Zhuangzi had a butterfly dream in ancient times. Because the dream is true, because the dream is puzzled, because the soul phenomenon is puzzled, the question of "am I a butterfly or a person" is put forward.
The third question: I didn't hear the sound of sleeping, thunder and rain. Answer: I entered the fourth stage of slow-wave sleep (deep sleep stage). At this time, the subject is not only asleep, but also difficult to wake up. So it is normal to hear the sound of thunder and rain outside.
The fourth question: Why are dreams real? Answer: The perceptual growth model holds that although what you see and hear in your dream is illusory and did not exist at that time, first of all, the information carriers that reflect your dream, such as appearances and perceptual units, are all information records of objective and real things. So as long as you get excited energy, you will reflect the objective information of these real things, so the perception in your dream is also true. Second, because in the state of sleep, everything is inhibited except the only dream. As a result, people have lost their proper views on right and wrong, morality, evaluation criteria, discrimination and criticism, and the only dream can only be perceived as real.