Extrasensory perception

B. Rhine to denote psychic abilities such as intuition, telepathy, psychometry, clairvoyance, clairaudience, clairsentience, empathy and their trans-temporal operation as precognition or retrocognition.

B. Rhine worked largely in the laboratory, carefully defining terms such as ESP and psi and designing experiments to test them.

[10] 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".

[11] 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.

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.

[27][28][29][30][31][32][33] Skeptics have pointed out that there is no viable theory to explain the mechanism behind ESP, and that there are historical cases in which flaws have been discovered in the experimental design of parapsychological studies.

Trial-by-trial feedback given in studies using a "closed" ESP target sequence (e.g., a deck of cards) violates the condition of independence used for most standard statistical tests.

In the early 20th century, Joaquin María Argamasilla, known as the "Spaniard with X-ray Eyes", claimed to be able to read handwriting or numbers on dice through closed metal boxes.

Argamasilla managed to fool Gustav Geley and Charles Richet into believing he had genuine psychic powers.

[37] Science writer Martin Gardner has written that the ignorance of blindfold deception methods has been widespread in investigations into objects at remote locations from persons who claim to possess second sight.

Gardner documented various conjuring techniques psychics such as Rosa Kuleshova, Lina Anderson and Nina Kulagina have used to peek from their blindfolds to deceive investigators into believing they used second sight.