Whether there are ghosts in the world or not depends on different perspectives.
First, what is a ghost? Xu Shen of the Eastern Han Dynasty "Shuo Wen Jie Zi": "People are ghosts. From people, like ghosts. Ghost, 隂气, [gf]8cca[ gf] harm, from 厶. Xu Shen believes that the ultimate destination of people is ghosts, so the word ghost is from people. The upper half of the ghost word resembles a ghost head. What does a ghost head look like? Actually, it's a skeleton. A skeleton is a dead man's skull with no flesh and hair, and its eyes, nostrils, and mouth holes are shaped like ghost heads. Skeletons give people a psychological hint of darkness, death, and fear, so the characteristics of ghosts are that they belong to yin qi and can secretly harm people, so the right middle of the word ghost is from 厶. This should be the original meaning of ghost characters.
Second, there are no ghosts in the world. Ghosts belong to people. "Erya Interpretation" says: "The ghost is the return of words." "But man has both flesh and spirit. Originally, the word ghost was supposed to refer to the return of the body after death, and later gradually extended to the return of the spirit. "Poetry Xiaoya" said: "For ghosts, for ghosts." "Rite [gf]904b[gf]" says: "Listed among the ghosts and gods." The "Note" says: "The ghosts are the return of the spirits." "Liezi Tianrui Chapter" said: "The spirit is out of shape, and each belongs to its own eyes, so the so-called ghost." Ghosts, return also. Return to his home. "The spirits of men leave their bodies and return to their true houses, where their spirits return, hence the names of ghosts. From a materialist point of view, the spirit cannot exist independently of the body, and when the body dies out, the spirit dies with it. So, there are no ghosts in the world.
Third, there is a ghost in the heart. Ghosts, in the eyes of superstitious people, refer to the soul of a person after death. After death, judging from the current scientific experiments, there is no soul, and therefore no ghosts. But according to Xu Shen's explanation: "Ghosts, yin qi, thieves." "Out of fear of ghosts and gods, people often have an inexplicable fear of unknown things, and this fear is often regarded as ghosts, so there are no ghosts in the world, but there are ghosts in people's hearts. In this sense, the fear of darkness and death in the human heart is a ghost. The ghost in your heart is difficult to get rid of, and scaring yourself will scare others to death. In order to avoid suspicion of dark ghosts, the ancients proposed that "people do not do bad things, and they are not afraid of ghosts knocking on the door in the middle of the night." "The heart is selfless, the world is wide, and there is no ghost in the heart.