The term clairvoyance (from 17th century French with clair meaning "clear" and voyance meaning "vision") is used to refer to the ability to gain information about an object, person, location or physical event through means other than the known human senses, a form of extra-sensory perception. A person said to have the ability of clairvoyance is referred to as a clairvoyant ("one who sees clearly").
Claims for the existence of paranormal and psychic abilities such as clairvoyance are highly controversial. Parapsychology explores this possibility, but the existence of the paranormal is generally not accepted by the scientific community.
Clairvoyance and related phenomena throughout historyThere have been anecdotal reports of clairvoyance and 'clear' abilities throughout history in most cultures. Often clairvoyance has been associated with religious or shamanic figures, offices and practices. For example, ancient Hindu religious texts list clairvoyance amongst other forms of 'clear' experiencing, as siddhis, or 'perfections', skills that are yielded through appropriate meditation and personal discipline. But a large number of anecdotal accounts of clairvoyance are of the spontaneous variety among the general populace. For example, many people report seeing a loved one who has recently died before they have learned by other means that their loved one is deceased. While anecdotal accounts do not provide scientific proof of clairvoyance, such common experiences continue to motivate research into such phenomena.
The earliest record of somnambulistic clairvoyance is credited to the Marquis de Puységur, a follower of Mesmer, who in 1784 was treating a local dull-witted peasant named Victor Race. During treatment, Race reportedly would go into trance and undergo a personality change, becoming fluent and articulate, and giving diagnosis and prescription for his own disease as well as those of others. When he came out of the trance state he would be unaware of anything he had said or done. This behavior is somewhat reminiscent of the reported behaviors of the 20th century medical clairvoyant and psychic Edgar Cayce. It is reported that although Puységur used the term 'clairvoyance', he did not think of these phenomena as "paranormal", since he accepted mesmerism as one of the natural sciences.
Clairvoyance was a reported ability of some mediums during the spiritualist period of the late 19th and early 20th centuries, and psychics of many descriptions have claimed clairvoyant ability up to the present day.
Early researchers of clairvoyance included William Gregory (chemist), Gustav Pagenstecher, and Rudolf Tischner. These were largely qualitative experiments in which selected participants sought to identify a concealed target image, or to provide accurate information about the history of a target object. Charles Richet, the noted physiologist and, later, Ina Jephson, a member of the Society for Psychical Research, introduced more quantitative methods. A significant development in clairvoyance research came when J. B. Rhine, a psychologist at Duke University, introduced a standard methodology, with a standard statistical approach to analysing the data, as part of his research into extrasensory perception. Perhaps the best-known study of clairvoyance in recent times has been the US government-funded remote viewing project at SRI/SAIC during the 1970s through the mid-1990s; at least those studies amongst these that did not involve "agents" visiting or being otherwise aware of the target sites.
Some parapsychologists have proposed that our different functional labels (clairvoyance, telepathy, precognition, etc.) all refer to one basic underlying mechanism, although there is not yet any satisfactory theory for what that mechanism may be.
Parapsychological research studies of remote viewing and clairvoyance have produced favorable results significantly above chance, and meta-analysis of these studies increases the significance. For instance, at the Stanford Research Institute, in 1972, Harold Puthoff and Russell Targ initiated a series of human subject studies to determine whether participants (the viewers or percipients) could reliably identify and accurately describe salient features of remote locations or targets. In the early studies, a human sender was typically present at the remote location, as part of the experiment protocol. A three-step process was used, the first step being to randomly select the target conditions to be experienced by the senders. Secondly, in the viewing step, participants were asked to verbally express or sketch their impressions of the remote scene. Thirdly, in the judging step, these descriptions were matched by separate judges, as closely as possible, with the intended targets. The term remote viewing was coined to describe this overall process.
In order to explore the nature of remote viewing channel, the viewer in some experiments was secured in a double-walled copper-screened Faraday cage. Although this provided attenuation of radio signals over a broad range of frequencies, the researchers found that it did not alter the subject's remote viewing capability. They postulated that extremely low frequency (ELF) propagation might be involved, since Faraday cage screening is less effective in the ELF range. Such a hypothesis had previously been put forward by telepathy researchers in the Soviet Union.
The first paper by Puthoff and Targ on psychic research to appear in a mainstream peer-reviewed scientific journal was published in Nature in March 1974; in it, the team reported some degree of remote viewing success. One of the individuals involved in these initial studies at SRI was Uri Geller, a well-known celebrity psychic at the time. The research team reported witnessing some of Geller's trademark metal spoon-bending performances, but admitted that they were unable to conduct adequately controlled experiments to confirm any paranormal hypothesis about them.
Electroencephalography (EEG) techniques were also used by team to examine ESP phenomena. In these investigations, a sender, who was isolated in a visually opaque, electrically and acoustically shielded chamber, was stimulated at random by bursts of strobe-light flickers The experimenters reported that, for one receiver, differential alpha block on control and stimulus trials were observed, which showed that some information transfer had occurred. In contrast, this person's expressed statements of when the stimulus occurred were no different than that which would be expected by chance. The researches were unable to identify the physical parameters by which the EEG effect was mediated.
After the publication of these findings, various attempts to replicate the remote viewing findings were quickly carried out. Several of these follow-up studies, which involved viewing in group settings, reported some limited success. They included the use of face-to-face groups and remotely-linked groups using computer conferencing.
The various debates in the mainstream scientific literature prompted the editors of 'Proceedings of the IEEE' to invite Robert Jahn, then Dean of the School of Engineering at Princeton University, to write a comprehensive review of psychic phenomena from an engineering perspective. His paper published in February 1982, includes numerous references to remote viewing replication studies at the time.
Clairvoyance experiments involving Zener cards currently exist on the internet. One such online system, the Anima Project, gathers user results into a master database which is then analyzed using a variety of statistical techniques.