Destroy what destroys you
Regarding exorcism, the Catholic Encyclopedia says:
Exorcism is (1) the act of driving out, or warding off, demons, or evil spirits, from persons, places, or things, which are believed to be possessed or infested by them, or are liable to become victims or instruments of their malice; (2) the means employed for this purpose, especially the solemn and authoritative adjuration of the demon, in the name of God, or any of the higher power in which he is subject.
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In contrast, the rationalist perspective presents historical and medically-based views of possession phenomena in terms of epilepsy, schizophrenia, and possession trance disorder (PTD), a possible variant of dissociative identity disorder. Nothing evil or supernatural takes over the identity of the person with PTD. Nonetheless, exorcisms performed on mentally ill people continue to this day. […]
In DSM-IV, spirit possession falls under the category of Dissociative Disorder Not Otherwise Specified, with more specific research criteria (but not an official diagnosis) fitting Dissociative Trance Disorder (possession trance):
Dissociative trance disorder: single or episodic disturbances in the state of consciousness, identity, or memory that are indigenous to particular locations and cultures. Dissociative trance involves narrowing of awareness of immediate surroundings or stereotyped behaviors or movements that are experienced as being beyond one’s control. Possession trance involves replacement of the customary sense of personal identity by a new identity, attributed to the influence of a spirit, power, deity, or other person and associated with stereotyped involuntary movements or amnesia, and is perhaps the most common dissociative disorder in Asia. Examples include amok (Indonesia), bebainan (Indonesia), latah (Malaysia), pibloktoq (Arctic), ataque de nervios (Latin America), and possession (India). The dissociative or trance disorder is not a normal part of a broadly accepted collective cultural or religious practice.
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Will there be changes for Dissociative Trance Disorder (DTD) in DSM-5?