Editing Ghost (section)

==History==
[[File:Dumuzi aux enfers.jpg|thumb|upright=1.3|Ancient Sumerian [[cylinder seal]] impression showing the god [[Dumuzid the Shepherd|Dumuzid]] being tortured in the [[Kur|Underworld]] by ''[[gallu|galla]]'' demons]]

===Ancient Near East and Egypt===
{{Main article|Ghosts in Mesopotamian religions}}
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There are many references to [[ghosts in Mesopotamian religions]] – the religions of [[Sumer]], [[Babylon]], [[Assyria]], and other early states in [[Mesopotamia]]. Traces of these beliefs survive in the later [[Abrahamic religion]]s that came to dominate the region.<ref>{{cite book
 |title=The treasures of darkness: a history of Mesopotamian religion
 |author=Jacobsen, Thorkild
 |publisher=Yale University Press
 |year=1978
 |isbn=978-0-300-02291-9}}</ref> The concept of ghosts may predate many [[belief systems]].<ref>{{Cite book |title=Religion and Chinese Society: Ancient and Medieval China |date=2004 |publisher=The Chinese University of Hong Kong Press |isbn=978-962-996-123-7 |editor-last=Lagerwey |editor-first=John |page=174|doi=10.2307/j.ctv1z7kkfn |jstor=j.ctv1z7kkfn }}</ref> Ghosts were thought to be created at time of death, taking on the memory and personality of the dead person. They traveled to the netherworld, where they were assigned a position, and led an existence similar in some ways to that of the living.
Relatives of the dead were expected to make offerings of food and drink to the dead to ease their conditions. If they did not, the ghosts could inflict misfortune and illness on the living. Traditional healing practices ascribed a variety of illnesses to the action of ghosts, while others were caused by gods or demons.<ref name=black>{{cite book
 |title=Gods, demons, and symbols of ancient Mesopotamia: an illustrated dictionary
 |author1=Black, Jeremy A. |author2=Green, Anthony |author3=Rickards, Tessa |publisher=University of Texas Press
 |year=1992
 |isbn=978-0-292-70794-8}}</ref>
[[File:Gardiner G25 Glyph.svg|thumb|right|upright|Egyptian Akh glyph – The [[Egyptian soul|soul]] and spirit re-united after death]]
There was widespread belief in [[ghosts in ancient Egyptian culture]].
The [[Hebrew Bible]] contains few references to ghosts, associating spiritism with forbidden occult activities cf. [[Deuteronomy]] 18:11. The most notable reference is in the First [[Books of Samuel|Book of Samuel]] (I Samuel 28:3–19 KJV), in which a disguised [[Saul the King|King Saul]] has the [[Witch of Endor]] summon the spirit or ghost of [[Samuel]].

The [[Egyptian soul|soul]] and spirit were believed to exist after death, with the ability to assist or harm the living, and the possibility of a second death. Over a period of more than 2,500 years, Egyptian beliefs about the nature of the afterlife evolved constantly. Many of these beliefs were recorded in [[hieroglyph]] inscriptions, papyrus scrolls and tomb paintings. The Egyptian ''[[Book of the Dead]]'' compiles some of the beliefs from different periods of ancient Egyptian history.<ref>{{cite book |last=Goelet |first= Ogden |title= A Commentary on the Corpus of Literature and Tradition which constitutes the Book of Going Forth By Day |publisher= Chronicle Books |location= San Francisco |year=1998 |pages=139–170}}</ref>
In modern times, the fanciful concept of a mummy coming back to life and wreaking vengeance when disturbed has spawned a whole genre of horror stories and films.<ref name="Vieira2003">{{cite book|author=Vieira, Mark A.|title=Hollywood horror: from gothic to cosmic|url=https://archive.org/details/hollywoodhorrorf0000viei|url-access=registration|year=2003|publisher=Harry N. Abrams|isbn=978-0-8109-4535-7|pages=[https://archive.org/details/hollywoodhorrorf0000viei/page/55 55]–58}}</ref>

===Classical Antiquity===
{{further|Shade (mythology)|Magic in the Greco-Roman world}}

====Archaic and Classical Greece====
[[File:Klytaimnestra Erinyes Louvre Cp710.jpg|thumb|Apulian red-figure [[bell krater]] depicting the ghost of [[Clytemnestra]] waking the [[Erinyes]], date unknown]]

Ghosts appeared in [[Homer]]'s ''[[Odyssey]]'' and ''[[Iliad]]'', in which they were described as vanishing "as a vapor, gibbering and whining into the earth". Homer's ghosts had little interaction with the world of the living. Periodically they were called upon to provide advice or prophecy, but they do not appear to be particularly feared. Ghosts in the classical world often appeared in the form of vapor or smoke, but at other times they were described as being substantial, appearing as they had been at the time of death, complete with the wounds that killed them.<ref>Finucane, pp. 4, 16</ref>

By the 5th century BC, [[classical Greece|classical Greek]] ghosts had become haunting, frightening creatures who could work to either good or evil purposes. The spirit of the dead was believed to hover near the resting place of the corpse, and cemeteries were places the living avoided. The dead were to be ritually mourned through public ceremony, sacrifice, and libations, or else they might return to haunt their families. The ancient Greeks held annual feasts to honor and placate the spirits of the dead, to which the family ghosts were invited, and after which they were "firmly invited to leave until the same time next year."<ref>Finucane, pp. 8–11</ref>

The 5th-century BC play ''[[Oresteia]]'' includes an appearance of the ghost of [[Clytemnestra]], one of the first ghosts to appear in a work of fiction.<ref>{{Cite journal|last1=Trousdell|first1=Richard|title=Tragedy and Transformation: The Oresteia of Aeschylus|journal=Jung Journal|volume=2|issue=3|pages=5–38|jstor=10.1525/jung.2008.2.3.5|doi=10.1525/jung.2008.2.3.5|year=2008|s2cid=170372385}}</ref>

====Roman Empire and Late Antiquity====
[[File:Athenodorus - The Greek Stoic Philosopher Athenodorus Rents a Haunted House.jpg|thumb|left|''[[Athenodoros Cananites|Athenodorus]] and the Ghost'', by [[Henry Justice Ford]], {{Circa|1900}}]]
The [[ancient Rome|ancient Romans]] believed a ghost could be used to exact revenge on an enemy by scratching a curse on a piece of lead or pottery and placing it into a grave.<ref>Finucane, pg 12</ref>

[[Plutarch]], in the 1st century AD, described the haunting of the baths at [[Chaeronea]] by the ghost of a murdered man. The ghost's loud and frightful groans caused the people of the town to seal up the doors of the building.<ref>Finucane, pg 13</ref> Another celebrated account of a haunted house from the ancient classical world is given by [[Pliny the Younger]] ({{circa|50 AD}}).<ref>{{cite web|url=http://www.siu.edu/news/ghosts.html |title=Classical ghost stories |last=Jaehnig |first=K.C. |date=1999-03-11 |publisher= Southern Illinois University |archive-url= https://web.archive.org/web/20070908171955/http://www.siu.edu/news/ghosts.html |access-date=2007-09-19 |archive-date= September 8, 2007}}</ref> Pliny describes the haunting of a house in [[Athens]], which was bought by the [[Stoicism|Stoic]] philosopher [[Athenodorus Cananites|Athenodorus]], who lived about 100 years before Pliny. Knowing that the house was supposedly haunted, Athenodorus intentionally set up his writing desk in the room where the apparition was said to appear and sat there writing until late at night when he was disturbed by a ghost bound in chains. He followed the ghost outside where it indicated a spot on the ground. When Athenodorus later excavated the area, a shackled skeleton was unearthed. The haunting ceased when the skeleton was given a proper reburial.<ref>{{cite web |url=http://www.bartleby.com/9/4/1083.html |title=LXXXIII. To Sura |author=Pliny the Younger |website=bartleby.com |access-date=2007-09-19 |archive-date=2007-10-12 |archive-url=https://web.archive.org/web/20071012164531/http://bartleby.com/9/4/1083.html |url-status=live }}</ref> The writers [[Plautus]] and [[Lucian]] also wrote stories about haunted houses.

In the [[New Testament]], according to [[Gospel of Luke|Luke]] 24:37–39,<ref>{{cite web|url=https://www.biblegateway.com/passage/?search=luke+24%3A37-39|archive-url=https://web.archive.org/web/20180926031745/https://www.biblegateway.com/passage/?search=luke+24%3A37-39|archive-date=26 September 2018|title=Luke 24:37-39 - They were startled and frightened, - Bible Gateway|date=26 September 2018}}</ref> following his [[resurrection of Jesus|resurrection]], [[Jesus]] was forced to persuade the [[Twelve Apostles|Disciples]] that he was not a ghost (some versions of the Bible, such as the KJV and NKJV, use the term "spirit"). Similarly, Jesus' followers at first believed he was a ghost (spirit) when they saw him [[Jesus walking on water|walking on water]].

One of the first persons to express disbelief in ghosts was [[Lucian of Samosata]] in the 2nd century AD. In his satirical novel ''[[Lover of Lies|The Lover of Lies]]'' ({{circa}} 150 AD), he relates how [[Democritus]] "the learned man from [[Abdera, Thrace|Abdera]] in [[Thrace]]" lived in a tomb outside the [[city gate]]s to prove that cemeteries were not haunted by the spirits of the departed. Lucian relates how he persisted in his disbelief despite [[practical joke]]s perpetrated by "some young men of Abdera" who dressed up in black robes with skull masks to frighten him.<ref>"The Doubter" by Lucian in Roger Lancelyn Green (1970) ''Thirteen Uncanny Tales''. London, Dent: 14–21; and Finucane, pg 26.</ref> This account by Lucian notes something about the popular classical expectation of how a ghost should look.

In the 5th century AD, the Christian priest [[Constantius of Lyon]] recorded an instance of the recurring theme of the improperly buried dead who come back to haunt the living, and who can only cease their haunting when their bones have been discovered and properly reburied.<ref>F. R. Hoare, ''The Western Fathers'', Sheed & Ward: New York, 1954, pp. 294–5.</ref>

===Middle Ages===
Ghosts reported in [[Middle Ages|medieval Europe]] tended to fall into two categories: the souls of the dead, or demons. The souls of the dead returned for a specific purpose. Demonic ghosts existed only to torment or tempt the living. The living could tell them apart by demanding their purpose in the name of Jesus Christ. The soul of a dead person would divulge its mission, while a demonic ghost would be banished at the sound of the Holy Name.<ref>Finucane, Ch. 3</ref>

Most ghosts were souls assigned to [[Purgatory]], condemned for a specific period to atone for their transgressions in life. Their penance was generally related to their sin. For example, the ghost of a man who had been abusive to his servants was condemned to tear off and swallow bits of his own tongue; the ghost of another man, who had neglected to leave his cloak to the poor, was condemned to wear the cloak, now "heavy as a church tower". These ghosts appeared to the living to ask for prayers to end their suffering. Other dead souls returned to urge the living to confess their sins before their own deaths.<ref>Fincucane, pp. 70–77.</ref>

Medieval European ghosts were more substantial than ghosts described in the [[Victorian era|Victorian age]], and there are accounts of ghosts being wrestled with and physically restrained until a priest could arrive to hear its confession. Some were less solid, and could move through walls. Often they were described as paler and sadder versions of the person they had been while alive, and dressed in tattered gray rags. The vast majority of reported sightings were male.<ref>Finucane, pp. 83–84.</ref>

There were some reported cases of ghostly armies, fighting battles at night in the forest, or in the remains of an [[Iron Age]] hillfort, as at [[Wandlebury]], near Cambridge, England. Living knights were sometimes challenged to single combat by phantom knights, which vanished when defeated.<ref name="Finucanepg">Finucane, pg. 79.</ref>

From the medieval period an apparition of a ghost is recorded from 1211, at the time of the [[Albigensian Crusade]].<ref>[[Mark Gregory Pegg]] (2008) ''A Most Holy War''. [[Oxford University Press]], New York: 3–5, 116–117. {{ISBN|978-0-19-517131-0}}</ref> [[Gervase of Tilbury]], Marshal of [[Arles]], wrote that the image of Guilhem, a boy recently murdered in the forest, appeared in his cousin's home in [[Beaucaire, Gard|Beaucaire]], near [[Avignon]]. This series of "visits" lasted all of the summer. Through his cousin, who spoke for him, the boy allegedly held conversations with anyone who wished, until the local priest requested to speak to the boy directly, leading to an extended disquisition on theology. The boy narrated the trauma of death and the unhappiness of his fellow souls in Purgatory, and reported that God was most pleased with the ongoing Crusade against the [[Cathar]] heretics, launched three years earlier. The time of the Albigensian Crusade in southern France was marked by intense and prolonged warfare, this constant bloodshed and dislocation of populations being the context for these reported visits by the murdered boy.

Haunted houses are featured in the 9th-century ''[[One Thousand and One Nights|Arabian Nights]]'' (such as the tale of ''[[list of stories within One Thousand and One Nights|Ali the Cairene and the Haunted House in Baghdad]]'').<ref>{{cite book |title=The Arabian Nights and Orientalism: Perspectives from East & West |url=https://archive.org/details/arabiannightsori00yama |url-access=limited |last=Yuriko Yamanaka |first=Tetsuo Nishio |publisher=[[I.B. Tauris]] |year=2006 |isbn=978-1-85043-768-0 |page=[https://archive.org/details/arabiannightsori00yama/page/n101 83]}}</ref>

===European Renaissance to Romanticism===
[[File:File-Hamlet, Prince of Denmark Act I Scene IV.png|thumb|right|"[[Hamlet]] and his father's ghost" by [[Henry Fuseli]] (1796 drawing). The ghost is wearing stylized [[plate armor]] in 17th-century style, including a [[morion (helmet)|morion]] type helmet and [[tassets]]. Depicting ghosts as wearing armor, to suggest a sense of antiquity, was common in [[Elizabethan theater]].]]
[[Renaissance magic]] took a revived interest in the [[occult]], including [[necromancy]]. In the era of the Reformation and Counter Reformation, there was frequently a backlash against unwholesome interest in the dark arts, typified by writers such as [[Thomas Erastus]].<ref>Walker, D.P. (1958) ''Spiritual and Demonic Magic from Ficino to Campanella.'' London: Warburg Institute, passim.</ref> The Swiss Reformed pastor [[Ludwig Lavater]] supplied one of the most frequently reprinted books of the period with his ''Of Ghosts and Spirits Walking By Night.''<ref>Original German edition: ''Von Gespänsten ..., kurtzer und einfaltiger bericht,'' Zürich, 1569 [VD16 L 834]</ref>

The [[Child Ballads|Child Ballad]] "[[Sweet William's Ghost]]" (1868) recounts the story of a ghost returning to his fiancée begging her to free him from his promise to marry her. He cannot marry her because he is dead but her refusal would mean his damnation. This reflects a popular British belief that the dead haunted their lovers if they took up with a new love without some formal release.<ref>[[Francis James Child|Child, Francis James]], ''The English and Scottish Popular Ballads'', v. 2, p. 227, Dover Publications, New York 1965</ref> "[[The Unquiet Grave]]" expresses a belief even more widespread, found in various locations over Europe: ghosts can stem from the excessive grief of the living, whose mourning interferes with the dead's peaceful rest.<ref>Child, Francis James, ''The English and Scottish Popular Ballads'', v 2, p 234, Dover Publications, New York 1965</ref> In many folktales from around the world, the hero arranges for the burial of a dead man. Soon after, he gains a companion who aids him and, in the end, the hero's companion reveals that he is in fact the [[Grateful dead (folklore)|dead man]].<ref name="encybrit">{{cite encyclopedia|url=https://www.britannica.com/EBchecked/topic/242238/grateful-dead#23476.hook|title=Grateful dead|encyclopedia=Encyclopædia Britannica Online|year=2007|access-date=2007-12-14|archive-date=2008-04-28|archive-url=https://web.archive.org/web/20080428201820/http://www.britannica.com/EBchecked/topic/242238/grateful-dead#23476.hook|url-status=live}}</ref> Instances of this include the Italian [[fairy tale]] "[[Fair Brow]]" and the Swedish "[[The Bird 'Grip']]".

===Modern period of western culture===

====Spiritualist movement====
[[File:Spirit rappings coverpage to sheet music 1853.jpg|thumb|left|upright|By 1853, when the popular song ''Spirit Rappings'' was published, Spiritualism was an object of intense curiosity.]]<!--

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[[Spiritualism (movement)|Spiritualism]] is a [[monotheism|monotheistic]] belief system or [[religion]], postulating a belief in [[God]], but with a distinguishing feature of belief that spirits of the dead residing in the [[spirit world (Spiritualism)|spirit world]] can be contacted by "[[mediumship|mediums]]", who can then provide information about the [[afterlife]].<ref name="Carroll">{{cite book
 | last = Carroll
 | first = Bret E.
 | year = 1997
 | title = Spiritualism in Antebellum America. (Religion in North America.)
 | publisher = Bloomington: Indiana University Press
 | isbn = 978-0-253-33315-5
 | page = 248}}</ref>

Spiritualism developed in the United States and reached its peak growth in membership from the 1840s to the 1920s, especially in [[English-speaking world|English-language countries]].<ref name=Braude>{{cite book
 | last = Braude
 | first = Ann
 | year = 2001
 | title = Radical Spirits: Spiritualism and Women's Rights in Nineteenth-Century America, Second Edition
 | publisher = Indiana University Press
 | isbn = 978-0-253-21502-4
 | page = 296}}
</ref><ref name="Britten">{{cite book |last= Britten |first= Emma Hardinge |author-link= Emma Hardinge Britten |title= Nineteenth Century Miracles: Spirits and their Work in Every Country of the Earth |url= https://archive.org/details/nineteenthcentu00britgoog |publisher= New York: William Britten |year= 1884 |isbn=978-0-7661-6290-7}}</ref> By 1897, it was said to have more than eight million followers in the United States and Europe,<ref name="NYT">{{cite news |title=THREE FORMS OF THOUGHT; M.M. Mangassarian Addresses the Society for Ethical Culture at Carnegie Music Hall. UNREST OF THE HUMAN MIND Theosophy, Spiritualism, and Christian Science Discussed -- The Theory of Reaction a Fallacy -- Ineffectiveness of the Spiritualistic Idea |url=https://www.nytimes.com/1897/11/29/archives/three-forms-of-thought-mm-mangassarian-addresses-the-society-for.html |work=The New York Times |date=29 November 1897 |access-date=4 November 2019 |archive-date=4 November 2019 |archive-url=https://web.archive.org/web/20191104152314/https://www.nytimes.com/1897/11/29/archives/three-forms-of-thought-mm-mangassarian-addresses-the-society-for.html |url-status=live }}</ref> mostly drawn from the [[middle class|middle]] and [[upper class|upper]] classes, while the corresponding movement in continental Europe and Latin America is known as [[#Spiritism|Spiritism]].

The religion flourished for a half century without canonical texts or formal organization, attaining cohesion by periodicals, tours by trance lecturers, camp meetings, and the missionary activities of accomplished mediums.<ref>{{Cite book|title = Supernatural Entertainments: Victorian Spiritualism and the Rise of Modern Media Culture|last = Natale|first = Simone|publisher = Pennsylvania State University Press|year = 2016|isbn=978-0-271-07104-6|location = University Park, PA}}</ref> Many prominent Spiritualists were women. Most followers supported causes such as the [[abolitionism|abolition of slavery]] and [[women's suffrage]].<ref name="Braude"/> By the late 1880s, credibility of the informal movement weakened, due to accusations of fraud among mediums, and formal Spiritualist organizations began to appear.<ref name="Braude"/> Spiritualism is currently practiced primarily through various denominational [[Spiritualist church]]es in the United States and United Kingdom.

====Spiritism====
<!--
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Spiritism, or French spiritualism, is based on the five books of the [[Spiritist Codification]] written by French educator Hypolite Léon Denizard Rivail under the [[pseudonym]] [[Allan Kardec]] reporting [[séance]]s in which he observed a series of phenomena that he attributed to incorporeal intelligence (spirits). His assumption of spirit communication was validated by many contemporaries, among them many scientists and philosophers who attended séances and studied the phenomena. His work was later extended by writers like [[Leon Denis]], [[Arthur Conan Doyle]], [[Camille Flammarion]], [[Ernesto Bozzano]], [[Chico Xavier]], Divaldo Pereira Franco, Waldo Vieira, [[Johannes Greber]],<ref>[http://www.seanet.com/~raines/greber.html Johannes Greber] {{webarchive|url=https://web.archive.org/web/20090316063452/http://www.seanet.com/~raines/greber.html |date=2009-03-16 }} Seanet.com Retrieved on 2013-03-21</ref> and others.

Spiritism has adherents in many countries throughout the world, including Spain, United States, Canada,<ref>In Canada, Spiritism is an officially recognized religious denomination (unique in the world) as [http://allankardec.ca/m.php?page=aksg_other_groups_in_canada.html The National Spiritist Church of Alberta] {{webarchive|url=https://web.archive.org/web/20100504090527/http://allankardec.ca/m.php?page=aksg_other_groups_in_canada.html |date=2010-05-04 }} (Church #A145 registered by Department of Vital Statistics, Government of Alberta – under The Marriage Act of Alberta) with government-licensed clergy and legal authority to perform marriages.</ref> Japan, Germany, France, England, Argentina, Portugal, and especially Brazil, which has the largest proportion and greatest number of followers.<ref>{{cite book |last=Hess |first=David |title=Spirits and Scientists: Ideology, Spiritism, and Brazilian Culture |publisher=Pennsylvania State University Press |year=1991 |isbn=978-0-271-00724-3 |url-access=registration |url=https://archive.org/details/spiritsscientist0000hess }}</ref>

===Scientific view===
{{See also|Paranormal}}
The physician [[John Ferriar]] wrote "An Essay Towards a Theory of Apparitions" in 1813 in which he argued that sightings of ghosts were the result of [[optical illusion]]s. Later the French physician [[Alexandre Jacques François Brière de Boismont]] published ''On Hallucinations: Or, the Rational History of Apparitions, Dreams, Ecstasy, Magnetism, and Somnambulism'' in 1845 in which he claimed sightings of ghosts were the result of [[hallucinations]].<ref>McCorristine, Shane ''Spectres of the Self: Thinking About Ghosts and Ghost-Seeing in England, 1750–1920'' 2010, {{ISBN|1-139-78882-5}} pp. 44–56</ref><ref>Gelder, Ken ''The horror reader'' 2000, {{ISBN|0-415-21356-8}} pp. 43–44</ref>

[[File:Ball lightning.png|thumb|A 1901 depiction of [[ball lightning]]]]

David Turner, a retired physical chemist, suggested that [[ball lightning]] could cause inanimate objects to move erratically.<ref>{{cite magazine |last=Muir |first=Hazel |title=Ball lightning scientists remain in the dark |url=https://www.newscientist.com/article/dn1720 |magazine=New Scientist |date=2001-12-20 |access-date=2011-01-15 |archive-date=2018-09-17 |archive-url=https://web.archive.org/web/20180917143403/https://www.newscientist.com/article/dn1720-ball-lightning-scientists-remain-in-the-dark/ |url-status=live }}</ref>

[[Joe Nickell]] of the [[Committee for Skeptical Inquiry]] wrote that there was no credible [[scientific evidence]] that any location was inhabited by spirits of the dead.<ref name = "CSICOP">{{cite web |url=http://www.csicop.org/si/show/haunted_inns_tales_of_spectral_guest |title=Haunted Inns Tales of Spectral Guests |last=Nickell |first=Joe |author-link=Joe Nickell |date=Sep–Oct 2000 |publisher=[[Committee for Skeptical Inquiry]] |access-date=2009-12-19 |archive-date=2010-01-17 |archive-url=https://web.archive.org/web/20100117150357/http://www.csicop.org/si/show/haunted_inns_tales_of_spectral_guest |url-status=live }}</ref> Limitations of [[perception|human perception]] and ordinary physical explanations can account for ghost sightings; for example, [[air pressure]] changes in a home causing doors to slam, humidity changes causing boards to creak, [[Failure of electronic components|condensation in electrical connections]] causing intermittent behavior, or lights from a passing car reflected through a window at night. [[Pareidolia]], an innate tendency to recognize patterns in random perceptions, is what some skeptics believe causes people to believe that they have 'seen ghosts'.<ref>{{cite web |url=http://skepdic.com/pareidol.html |title=pareidolia |last=Carroll |first=Robert Todd |date=June 2001 |website=skepdic.com |access-date=2007-09-19 |archive-date=2007-09-04 |archive-url=https://web.archive.org/web/20070904011810/http://skepdic.com/pareidol.html |url-status=live }}</ref> Reports of ghosts "seen out of the corner of the eye" may be accounted for by the sensitivity of human [[peripheral vision]]. According to Nickell, peripheral vision can easily mislead, especially late at night when the brain is tired and more likely to misinterpret sights and sounds.<ref name=visit>{{cite web |url=http://www.csicop.org/sb/show/paranormal_visit/ |title=The Paranormal Visit |last=Weinstein |first=Larry |date=June 2001 |publisher=Committee for Skeptical Inquiry |access-date=2010-02-12 |archive-url=https://web.archive.org/web/20100316131532/http://www.csicop.org/sb/show/paranormal_visit/ |archive-date=2010-03-16 }}
: "Once the idea of a ghost appears in a household ... no longer is an object merely mislaid .... There gets to be a dynamic in a place where the idea that it's haunted takes on a life of its own. One-of-a-kind quirks that could never be repeated all become further evidence of the haunting."</ref> Nickell further states, "science cannot substantiate the existence of a 'life energy' that could survive death without dissipating or function at all without a brain... why would... clothes survive?'" He asks, if ghosts glide, then why do people claim to hear them with "heavy footfalls"? Nickell says that ghosts act the same way as "dreams, memories, and imaginings, because they too are mental creations. They are evidence – not of another world, but of this real and natural one."<ref>{{cite journal|last1=Nickell|first1=Joe|author-link=Joe Nickell|title=Hawking 'Ghosts' in Old Louisville|journal=Skeptical Inquirer|date=2018|volume=42|issue=2|pages=26–29}}</ref>

[[Benjamin Radford]] from the [[Committee for Skeptical Inquiry]] and author of the 2017 book ''Investigating Ghosts: The Scientific Search for Spirits'' writes that "ghost hunting is the world's most popular paranormal pursuit" yet, to date, ghost hunters cannot agree on what a ghost is, or offer proof that they exist; "it's all speculation and guesswork". He writes that it would be "useful and important to distinguish between types of spirits and apparitions. Until then it's merely a parlor game distracting amateur ghost hunters from the task at hand."<ref name="Radford 2018">{{cite journal|last1=Radford|first1=Ben|author-link=Ben Radford|title=The Curious Question of Ghost Taxonomy|journal=Skeptical Inquirer|date=2018|volume=42|issue=3|pages=47–49}}</ref>

According to research in [[anomalistic psychology]] visions of ghosts may arise from [[hypnagogia|hypnagogic]] hallucinations ("waking dreams" experienced in the transitional states to and from sleep).<ref>{{cite journal|author=Klemperer, Frances|year=1992|title=Ghosts, Visions, and Voices: Sometimes Simply Perceptual Mistakes|journal= British Medical Journal |volume= 305|issue=6868 |pages=1518–1519|jstor=29717993|doi=10.1136/bmj.305.6868.1518|pmid=1286367|pmc=1884722}}</ref> In a study of two experiments into alleged [[hauntings]] (Wiseman ''et al.''. 2003) came to the conclusion "that people consistently report unusual experiences in 'haunted' areas because of environmental factors, which may differ across locations." Some of these factors included "the variance of local magnetic fields, size of location and lighting level stimuli of which witnesses may not be consciously aware".<ref>{{cite journal |author1=Wiseman, R. |author2=Watt, C. |author3=Stevens, P. |year=2003 |url=http://www.richardwiseman.com/resources/BJP-hauntings.pdf |archive-url=https://web.archive.org/web/20080829021019/http://www.richardwiseman.com/resources/BJP-hauntings.pdf |archive-date=2008-08-29 |url-status=live |title=An investigation into alleged "hauntings" |journal=The British Journal of Psychology |volume=94 |pages=195–211 |doi=10.1348/000712603321661886 |pmid=12803815 |issue=2 |display-authors=etal |citeseerx=10.1.1.537.2406 }}</ref>

Some researchers, such as [[Michael Persinger]] of [[Laurentian University]], Canada, have speculated that changes in [[geomagnetic]] fields (created, e.g., by tectonic stresses in the Earth's crust or [[solar variation|solar activity]]) could stimulate the brain's [[temporal lobe]]s and produce many of the experiences associated with hauntings.<ref>[http://www.richardwiseman.com/research/ghosts.html Richard Wiseman] {{Webarchive|url=https://web.archive.org/web/20070830042118/http://www.richardwiseman.com/research/ghosts.html |date=2007-08-30 }}. Retrieved September 25, 2007.</ref> Sound is thought to be another cause of supposed sightings. Richard Lord and [[Richard Wiseman]] have concluded that [[infrasound]] can cause humans to experience bizarre feelings in a room, such as anxiety, extreme sorrow, a feeling of being watched, or even the chills.<ref name=sound>{{cite web |url=http://www.smh.com.au/articles/2003/09/08/1062901994082.html?oneclick=true |title=Sounds like terror in the air |date=2003-09-09 |website=Reuters |publisher=[[Sydney Morning Herald]] |access-date=2007-09-19 |archive-date=2007-10-22 |archive-url=https://web.archive.org/web/20071022151033/http://www.smh.com.au/articles/2003/09/08/1062901994082.html?oneclick=true |url-status=live }}</ref> [[carbon monoxide poisoning#Haunted houses|Carbon monoxide poisoning]], which can cause changes in perception of the visual and auditory systems,<ref name="pmid11410684">{{cite journal|author=Choi IS|title=Carbon monoxide poisoning: systemic manifestations and complications|journal=J. Korean Med. Sci.|volume=16|issue=3|pages=253–61|year=2001|pmid=11410684|doi=10.3346/jkms.2001.16.3.253|pmc=3054741}}</ref> was speculated upon as a possible explanation for [[haunted house]]s as early as 1921.

People who experience [[sleep paralysis]] often report seeing ghosts during their experiences. Neuroscientists Baland Jalal and [[Vilayanur S. Ramachandran|V.S. Ramachandran]] have recently proposed neurological theories for why people hallucinate ghosts during sleep paralysis. Their theories emphasize the role of the [[parietal lobe]] and [[mirror neuron]]s in triggering such ghostly hallucinations.<ref>{{Cite journal|last1=Jalal|first1=Baland|last2=Romanelli|first2=Andrea|last3=Hinton|first3=Devon E.|date=2015-12-01|title=Cultural Explanations of Sleep Paralysis in Italy: The Pandafeche Attack and Associated Supernatural Beliefs|journal=Culture, Medicine, and Psychiatry|language=en|volume=39|issue=4|pages=651–664|doi=10.1007/s11013-015-9442-y|pmid=25802016|s2cid=46090345|issn=0165-005X}}</ref>