Below is a link to an entire glossary of parapsychology terms, containing entries for telepathy, precognition and clairvoyance among others.
Clairvoyance: Paranormal acquisition of information concerning an object or contemporary physical event; in contrast to telepathy, the information is assumed to derive directly from an external physical source (such as a concealed photograph), and not from the mind of another person.
Telepathy: paranormal acquisition of information concerning the thoughts, feelings or activity of another conscious being; the word has superseded earlier expressions such as “thought-transference.”
Precognition: A form of extrasensory perception in which the target is some future event that cannot be deduced from normally known data in the present.
These are clearly defined terms in parapsychology.
Telepathy is what most people would call the ability to read minds. It is the ability to send or receive thoughts, images, feelings, or impressions from one person to another without the use of physical instruments, like the body.
Precognition is what most people would consider fortune telling or predicting the future. It is the sensation of having knowledge of an event before it occurs. Literally, “pre” means before, and “cognition” relates to knowing. So, the term involves knowing before something occurs.
Clairvoyance relates to knowing something that you could not possibly perceived with your normal senses. Essentially it refers to “knowing at a distance”. This is typically recorded when a person sees an image of a relative or friend who has been in an accident many miles away. Or, somebody having a dream that a relative is ill on the night that they become ill. These are considered to be clairvoyant events. The difference between clairvoyance and precognition is that clairvoyance involves knowing at the time that the event occurs, while precognition involves knowing before an event occurs.
Research has been done on each of these abilities in psychology labs around the world. Items like clairvoyance are difficult to test due to the rarity of the events, but telepathy and precognition have been tested. Some results definitively provide strong evidence that these abilities exist, while other results have been questioned by those who critically examine the experiments and the statistical analysis of the research. An interesting experiment regarding precognition involves involuntary pupil contraction when exposed to bright lights. Recent experiments have demonstrated that some people repeatedly show a contraction of their pupils milliseconds before the stimuli is actually presented, demonstrating the anticipation of the event occuring. Though this is not impressive on a macro scale, it is a definite indication that some sort of pre-knowledge of the event is unconciously causing the pupils to retract before the stimuli is presenting itself (Radin, 2007).
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