Reputed ghost of a monk. Taken in a church in England
Ghosts are the supposed apparitions of the dead. A ghost is often thought to be the spirit or soul of a person who has remained on Earth after death. Every culture in the world carries stories about ghosts, but its beliefs vary substantially across time and place, with disagreements both as to what ghosts are and whether such things exist in reality.
In Asian cultures (such as China), many people believe in reincarnation. Ghosts are those souls that refused to be 'recycled' because they have unfinished business similar to those in western belief. Exorcistss can either help a ghost to be reincarnated or blow it out of existence. In Chinese belief, apart from being reincarnated, a ghost can also become immortal and become a demigod, or it can go to hell and suffer for eternity, or it can die again and become "ghost of ghost".
Both the West and the East share some fundamentals about ghosts. They may wonder around places where they frequent when alive, or where they have died. Such places where ghosts frequent are known as "haunteded"; the rounds they go on are known as "hauntings". Ghosts do not have a physical body like human beings. They often wear the sort of clothing in which they would have been seen when alive.
Skeptics seek to explain ghost sightings by applying the principle of Occam's razor, which involves selecting the simplest from all possible explanations for a phenomenon. This usually means that first, the sincerity and motive of the person reporting will be called into question. For example, lingering of ghosts is typically associated with seeking justice or revenge. Ascribing such motives and powers to dead people could be interpreted as a scare tactic directed at those who might consider murdering someone. Second, the possibility of a con will be considered, with the reporting person assumed to be the victim. It seems possible that, sometimes, the telling of ghost stories might have been a way for secluded communities to scare off intruders. It is also conceivable that, when unsuccessful, this tactic could have been backed up by more or less elaborate setups with members of that community playing ghosts. Third, explanations grounded in knowledge about human physiology will be proffered. For instance, the appearance of ghosts is often associated with a chilling sensation and pale, semitransparent figures instilling "negative energy". But a natural animal response to fear is hair-raising which can be mistaken for chill. The visual aspects could also be accounted for by human physiology: the peripheral vision is very sensitive for detecting motion, but does not contain color or provide focused shapes; therefore, a moving curtain or other movement outside the focused view can create a strong illusion of an eerie figure. The natural occurrence of infrasound, which are sounds below human auditory frequencies (below 20 hertz), could possibly explain the notions of feeling a 'presence' in the room, or unexplained feelings of anxiety or dread, as certain infrasonic frequencies are known to have these effects on the body. The frequency of 18hz is known to cause the human eye to vibrate, which can make pale forms appear in the peripheral vision. Psychological factors are also often cited as natural explanations for ghost sightings: susceptible people might be prone to exaggerated interpretations of perceptions when visiting a site of unpleasant historical events.
In Shakespeare's play Hamlet, a ghost taking the form of Hamlet's recently deceased father appears to Prince Hamlet one night. The ghost says that he was in fact murdered by his brother Claudius, who now (by virtue of having married Hamlet's mother Gertrude) occupies the throne. The ghost exhorts Hamlet to take revenge on Claudius. When Hamlet sees the ghost, he is not sure if it is in fact his father's spirit, or a demon whose aim is to deceive him.
In the Biblical account of the Witch of Endor, King Saul of Israel has the witch conjure up the ghost of the prophet Samuel to consult him on his precarious situation; the prophet's spirit gives the king no assistance, and foretells his doom instead.
In the Ghostbusters film and television franchise, the protagonists use special technology of their own design to hunt and capture/exile the ghosts they encounter.
In The Matrix, ghosts are explained as obsolete or malfunctioning programss which choose to hide in the matrix to escape deletion. A program's other option is to return to "the Source," which is like the Heaven of the matrix.
In Ghost in the Shell, ghost is a word used to describe a person's inner being, similar to the concept of a soul.
