There is no definitive distinction between scrying and other aids to
clairvoyance,
augury, or
divination, but roughly speaking, scrying depends on impressions of visions in the medium of choice. Ideally in this respect it differs from augury, which relies on interpretations of objectively observable objects or events (such as flight of birds); from divination, which depends on standardized processes or rituals; from
oneiromancy, which depends on the interpretation of dreams; from the physiological effects of
psychoactive drugs; and from clairvoyance, which notionally does not depend on objective sensory stimuli. Clairvoyance in other words, is regarded as amounting in essence to
extrasensory perception. Scrying is neither a single, clearly defined, nor formal discipline and there is no uniformity in the procedures, which repeatedly and independently have been reinvented or elaborated in many ages and regions. Furthermore, practitioners and writers coin terminology so arbitrarily, and often artificially, that no one system of nomenclature can be taken as authoritative and definitive. Commonly terms in use are
Latinisations or
Hellenisations of descriptions of the media or activities. Examples of names coined for crystal gazing include 'crystallomancy', 'spheromancy', and '
catoptromancy'. As an example of the looseness of such terms, catoptromancy should refer more specifically to scrying by use of mirrors or other reflective objects rather than by crystal gazing. Other
names that have been coined for the use of various scrying media include
anthracomancy for glowing coals, turifumy for scrying into smoke, and hydromancy for scrying into water. There is no clear limit to the coining and application of such terms and media. Scrying has been practiced in many cultures in the belief that it can reveal the past, present, or future. Some practitioners assert that visions that come when one stares into the media are from the
subconscious or
imagination, while others say that they come from
gods, spirits,
devils, or the
psychic mind, depending on the culture and practice. There is neither any systematic body of
empirical support for any such views in general however, nor for their respective rival merits; individual preferences in such matters are arbitrary. Alternatively the medium might reduce visual stimuli to thresholds below which any clear impressions could interfere with fancied visions or free association. Examples include darkened reflections of night sky, or plain shadow or darkness. == Methods ==