 | ||
Extrasensory perception, ESP or Esper, also called sixth sense, includes reception of information not gained through the recognized physical senses but sensed with the mind. The term was adopted by Duke University psychologist J. B. Rhine to denote psychic abilities such as intuition, telepathy, psychometry, clairaudience, and clairvoyance, and their trans-temporal operation as precognition or retrocognition.
Contents
Parapsychology is the study of paranormal psychic phenomena, including ESP. Parapsychology has been criticized for continuing investigation despite being unable to provide convincing evidence for the existence of any psychic phenomena after more than a century of research. The scientific community rejects ESP due to the absence of an evidence base, the lack of a theory which would explain ESP, the lack of experimental techniques which can provide reliably positive results, and considers ESP to be pseudoscience.
History
In the 1930s, at Duke University in North Carolina, J. B. Rhine and his wife Louisa E. Rhine conducted investigation into extrasensory perception. While Louisa Rhine concentrated on collecting accounts of spontaneous cases, J. B. Rhine worked largely in the laboratory, carefully defining terms such as ESP and psi and designing experiments to test them. A simple set of cards was developed, originally called Zener cards – now called ESP cards. They bear the symbols circle, square, wavy lines, cross, and star; there are five cards of each in a pack of 25.
In a telepathy experiment, the "sender" looks at a series of cards while the "receiver" guesses the symbols. To try to observe clairvoyance, the pack of cards is hidden from everyone while the receiver guesses. To try to observe precognition, the order of the cards is determined after the guesses are made. Later he used dice to test for psychokinesis.
The parapsychology experiments at Duke evoked criticism from academics and others who challenged the concepts and evidence of ESP. A number of psychological departments attempted to repeat Rhine's experiments with failure. W. S. Cox (1936) from Princeton University with 132 subjects produced 25,064 trials in a playing card ESP experiment. Cox concluded "There is no evidence of extrasensory perception either in the 'average man' or of the group investigated or in any particular individual of that group. The discrepancy between these results and those obtained by Rhine is due either to uncontrollable factors in experimental procedure or to the difference in the subjects." Four other psychological departments failed to replicate Rhine's results.
In 1938, the psychologist Joseph Jastrow wrote that much of the evidence for extrasensory perception collected by Rhine and other parapsychologists was anecdotal, biased, dubious and the result of "faulty observation and familiar human frailties". Rhine's experiments were discredited due to the discovery that sensory leakage or cheating could account for all his results such as the subject being able to read the symbols from the back of the cards and being able to see and hear the experimenter to note subtle clues.
In the 1960s parapsychologists became increasingly interested in the cognitive components of ESP, the subjective experience involved in making ESP responses, and the role of ESP in psychological life. This called for experimental procedures that were not limited to Rhine's favored forced-choice methodology. Such procedures have included dream telepathy experiments, and the ganzfeld experiments (a mild sensory deprivation procedure).
Skepticism
The scientific consensus does not view extrasensory perception as a real phenomenon.
Skeptics claim that there is a lack of a viable theory of the mechanism behind ESP, and that there are historical cases in which flaws have been discovered in the experimental design of parapsychological studies.