In religion and mythology, occultism and folklore, a demon (or daemon, daimon; from Greek daimôn) is a supernatural being described as a spirit; the original neutral Greek word daimon does not carry the negative connotation initially understood by implementation of the (New Testament Greek), and later ascribed to any cognate words sharing the root, originally intended to denote a Spirit or Spiritual being.
In Ancient Near Eastern religions as well as in the derived Abrahamic traditions, including ancient and medieval Christian demonology, a demon is considered an "unclean spirit" which may cause demonic possession, to be addressed with an act of exorcism. In Western occultism and Renaissance magic, which grew out of pagan Greco-Roman, a demon is considered a spiritual entity that may be conjured and controlled. Many of the demons in literature were once fallen angels, however there are many that say that they are born-forged from Hell itself.
The Greek term does not have any connotations of evil or malevolence. In fact, Eudaimonia, literally "good-spiritedness", is a term for "happiness". The term first acquired its now-current evil connotations in the Septuagint translation of the Hebrew Bible, informed by the mythology of the ancient Semitic religions. This connotation was inherited by the Koine text of the New Testament. The medieval and neo-medieval conception of a "demon" in Western civilization (see the Medieval grimoire called the Ars Goetia) derives seamlessly from the ambient popular culture of Late (Roman) Antiquity. Greco-Roman concepts of daemons that passed into Christian culture are discussed in the entry daemon, though it should be duly noted that the term referred only to a spiritual force, not a malevolent supernatural being. The Hellenistic "daemon" eventually came to include many Semitic and Near Eastern gods as evaluated by Christianity.
The supposed existence of demons is an important concept in many modern religions[who?] and occultist traditions. In some present-day cultures, demons are still feared in popular superstition, largely due to their alleged power to possess living creatures. In the contemporary Western occultist tradition (perhaps epitomized by the work of Aleister Crowley), a demon, such as Choronzon, the "Demon of the Abyss", is a useful metaphor for certain inner psychological processes ("inner demons"), though some may also regard it as an objectively real phenomenon. Some scholars believe that large portions of the demonology (see Asmodai) of Judaism, a key influence on Christianity and Islam, originated in Zoroastrianism, and were transferred to Judaism during the Persian era.
Psychologist Wilhelm Wundt remarks that "among the activities attributed by myths all over the world to demons, the harmful predominate, so that in popular belief bad demons are clearly older than good ones."
Sigmund Freud develops on this idea and claims that the concept of demons was derived from the important relation of the living to the dead: "The fact that demons are always regarded as the spirits of those who have died recently shows better than anything the influence of mourning on the origin of the belief in demons."
M. Scott Peck, an American psychiatrist, wrote two books on the subject, People of the Lie: The Hope For Healing Human Evil and Glimpses of the Devil: A Psychiatrist's Personal Accounts of Possession, Exorcism, and Redemption.
Peck describes in some detail several cases involving his patients. In People of the Lie: The Hope For Healing Human Evil he gives some identifying characteristics for evil persons whom he classifies as having a character disorder. In Glimpses of the Devil, A Psychiatrist's Personal Accounts of Possession, Exorcism, and Redemption Peck goes into significant detail describing how he became interested in exorcism in order to debunk the "myth" of possession by evil spirits–only to be convinced otherwise after encountering two cases which did not fit into any category known to psychology or psychiatry. Peck came to the conclusion that possession was a rare phenomenon related to evil. Possessed people are not actually evil; they are doing battle with the forces of evil. His observations on these cases are listed in the Diagnostic and Statistical Manual of Mental Disorders of the American Psychiatric Association.
Although Peck's earlier work was met with widespread popular acceptance, his work on the topics of evil and possession has generated significant debate and derision. Much was made of his association with (and admiration for) the controversial Malachi Martin, a Roman Catholic priest and a former Jesuit, despite the fact that Peck consistently called Martin a liar and manipulator. Other criticisms leveled against Peck include misdiagnoses based upon a lack of knowledge regarding dissociative identity disorder (formerly known as multiple personality disorder), and a claim that he had transgressed the boundaries of professional ethics by attempting to persuade his patients into accepting Christianity.
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