crystal vision

   A term used to denote a type of visual hallucination or *illusion that may arise during a period of fixed gazing into an opaque or reflecting object, such as a Braid's crystal, a glass of water, or a metal mirror. The ancient technique employed to call forth this type of hallucination is known as crystal gazing, crystallomancy, or scrying. When water or other liquids are employed, the term hydromancy is used. When oil is used, the term lecanomancy applies. It is believed that reflections of light within the medium of choice act as * points de repère for the formation of visual hallucinations. In biomedicine, the * visions thus evoked are variously classified as * reperceptions or as * release phenomena. They can also be classified as * cognitive illusions. The German hallucinations researcher Edmund Parish (1861-1916) holds that crystal-visions are typically experienced while one is fully awake and conscious. It has also been suggested, however, that a trancelike or self-hypnotic state is required to allow these phenomena to be conjured up. In parapsychology, crystallomancy is considered a mode of divination. As a corollary, the ensuing hallucinations are considered *veridical, *telepathic, or * coincidental in nature.

   References

   Melton, J.G., ed. (1996). Encyclopedia of occultism and parapsychology. Volume 1. Fourth edition. Detroit, MI: Gale.

   Parish, E. (1897). Hallucinations and illusions. A study ofthe fallacies ofperception. London: Walter Scott.

   Richet, C. (1975). Thirty years of psychical research. Translated by de Brath, S. New York, NY: Macmillan.