Telepathy comes from the Ancient Greek words têle meaning "distant" and páthos meaning "feeling, perception, or experience." It refers to the supposed transfer of information from one person's mind to another's without using any known senses or physical contact. The term was first created in 1882 by Frederic W. H. Myers, a classical scholar and founder of the Society for Psychical Research (SPR). This term became more widely used than the earlier term "thought-transference."

Experiments about telepathy have often been criticized for not having good controls or being able to be repeated. There is no strong evidence that telepathy exists, and most scientists view it as pseudoscience. Telepathy is a common idea in science fiction stories.

Origins of the concept

According to historians such as Roger Luckhurst and Janet Oppenheim, the idea of telepathy in Western culture began in the late 1800s with the creation of the Society for Psychical Research. As science made big progress, scientists tried to use scientific methods to study mental events, such as animal magnetism, in hopes of better understanding paranormal experiences. The modern idea of telepathy developed during this time.

Psychical researcher Eric Dingwall pointed out that early members of the Society for Psychical Research, Frederic W. H. Myers and William F. Barrett, focused on trying to show that telepathy was real, rather than looking at it in a fair and unbiased way to determine if it existed.

Thought reading

In the late 1800s, a magician named Washington Irving Bishop performed demonstrations that seemed to show he could read people’s thoughts. Bishop said he did not have magical or supernatural powers. Instead, he believed he could read thoughts by noticing small movements in people’s bodies, such as slight muscle movements. Scientists, including the editor of the British Medical Journal and psychologist Francis Galton, studied Bishop’s abilities. Bishop successfully completed tasks like finding a specific spot on a table or locating a hidden object. During these tests, he needed to touch a person who knew the correct answer, such as holding their hand or wrist. The scientists concluded that Bishop was not truly able to read minds through telepathy but instead used highly developed skills to detect tiny muscle movements.

Another well-known thought reader was the magician Stuart Cumberland. He performed tricks while blindfolded, such as identifying a hidden object in a room or describing a murder scene imagined by someone else and then guessing details like the victim and reenacting the crime. Cumberland said he did not have real psychic powers. He claimed his thought-reading tricks only worked when he held a person’s hand to observe their muscle movements. Cumberland had disagreements with researchers from the Society for Psychical Research, who were looking for real examples of telepathy. Cumberland argued that telepathy and communication with the dead were not possible. He believed people’s thoughts could not be read through telepathy but only by observing muscle movements.

Case studies

In the late 1800s, the Creery Sisters (Mary, Alice, Maud, Kathleen, and Emily) were tested by the Society for Psychical Research. They were believed to have real psychic abilities, but later experiments showed they used secret signals. They admitted to trickery. George Albert Smith and Douglas Blackburn were also believed to have real psychic powers by the same society. Blackburn later admitted to fraud.

For nearly thirty years, Mr. G. A. Smith and another person conducted telepathy experiments. These were considered strong evidence for thought transference. However, they later admitted the experiments were fake. They said they wanted to show how easily scientists could be tricked when looking for proof of a theory they wanted to believe.

Between 1916 and 1924, Gilbert Murray performed 236 telepathy experiments. He reported 36% as successful. However, others believed the results could be explained by hyperaesthesia, a condition where someone can hear what the sender is saying. Psychologist Leonard T. Troland tested telepathy at Harvard University in 1917. The results were below what would be expected by chance.

Arthur Conan Doyle and W. T. Stead believed Julius and Agnes Zancig had real psychic powers. Both wrote that the Zancigs performed telepathy. In 1924, the Zancigs admitted their act was a trick. They published the secret code and details of their method in a London newspaper.

In 1924, Robert H. Gault of Northwestern University and Gardner Murphy conducted the first American radio test for telepathy. The results showed no success. One experiment involved guessing a number between 1 and 1,000. Out of 2,010 attempts, none were correct. This was below the expected chance of two correct guesses.

In February 1927, with the help of the BBC, V. J. Woolley, a researcher for the SPR, arranged a telepathy experiment. Listeners were asked to identify objects thought about by people in an office. Over 24,659 answers were received, but no evidence of telepathy was found.

Upton Sinclair wrote about testing his wife, Mary Craig Sinclair, in his book Mental Radio. She tried to copy 290 pictures drawn by her husband. She successfully copied 65, had 155 partial successes, and 70 failures. However, the experiments were not done in a scientific lab. Science writer Martin Gardner suggested that sensory clues, like seeing pencil movements, might have influenced the results.

The Turner-Ownbey telepathy experiment had flaws. May Frances Turner and Sara Ownbey claimed to communicate over 250 miles. Turner wrote down symbols, and Ownbey guessed them. Scores were high, but Ownbey sent the results to Turner instead of J. B. Rhine. Critics said this made the results invalid. When repeated with Rhine, scores dropped to average.

In 1937, Harold Sherman and Hubert Wilkins tested telepathy for five and a half months. Sherman was in New York, and Wilkins was in the Arctic. Each day, they visualized events and wrote them in diaries. When compared, 60% of their entries matched. Their results were published in 1942 in a book titled Thoughts Through Space. However, magician John Booth said the matches were likely due to coincidence or guesswork. A review in the American Journal of Orthopsychiatry questioned the experiment’s validity because it was published five years after it was conducted.

In 1948, Maurice Fogel claimed to demonstrate telepathy on BBC radio. Journalist Arthur Helliwell discovered Fogel used tricks, like knowing audience details before shows. Helliwell exposed Fogel’s methods in a newspaper. While some believed Fogel, most knew he was a performer.

Samuel Soal and K. M. Goldney tested 160 people over 128,000 trials. They found no evidence of telepathy. Soal tested Basil Shackleton and Gloria Stewart over 20,000 guesses. Shackleton scored 2,890, and Gloria scored 9,410. Later, Gretl Albert saw Soal alter records. Betty Marwick found Soal did not use random number selection as claimed. This discredited all his experiments.

In 1979, physicists John G. Taylor and Eduardo Balanovski suggested electromagnetism (EM) might explain telepathy. Experiments showed EM levels were too low to support paranormal effects. No evidence of telepathy was found.

In parapsychology

In the field of parapsychology, telepathy, along with precognition and clairvoyance, is considered a part of extrasensory perception (ESP) or "anomalous cognition." Parapsychologists believe these abilities may be transferred through a hypothetical psychic mechanism called "psi." Parapsychologists have used experiments to test for telepathic abilities. Two well-known methods are the use of Zener cards and the Ganzfeld experiment.

Zener cards are marked with five different symbols. In an experiment, one person is the "sender," and another is the "receiver." The sender picks a card at random and visualizes the symbol, while the receiver tries to guess the symbol telepathically. Statistically, the receiver has a 20% chance of guessing correctly by chance. To show telepathy, the receiver must guess correctly much more often than 20%. However, this method can be flawed if sensory leakage (such as seeing or hearing clues) or card counting occurs.

J. B. Rhine’s experiments with Zener cards were later discredited because sensory leakage or cheating could explain his results. For example, subjects might have seen symbols on the back of the cards or noticed subtle clues from the experimenter. After Rhine improved his methods, he could not find any high-scoring subjects. Due to these issues, parapsychologists no longer use card-guessing studies.

Parapsychologists at Maimonides Medical Center in Brooklyn, New York, led by Stanley Krippner and Montague Ullman, studied dream telepathy. They claimed some of their experiments supported the idea, but other researchers have not repeated their findings. Psychologist James Alcock noted that the lack of independent replication weakens the evidence for telepathy.

The picture target experiments by Krippner and Ullman were criticized by C. E. M. Hansel. He pointed out flaws in the design, such as the experimenter knowing the target before the test was complete. Hansel also said the experiments had poor controls, as the main experimenter could communicate with the subject.

Edward Belvedere and David Foulkes tried to repeat the picture target experiments but found no evidence of telepathy. Their results, along with other studies, were negative.

In the Ganzfeld experiment, one person is the "receiver" and is placed in a controlled environment with no sensory input, while another person, the "sender," is in a separate location. The receiver tries to receive information from the sender. The type of information tested may vary.

Studies of the Ganzfeld experiment by Ray Hyman and Charles Honorton found many methodological problems. Honorton noted that only 36% of the studies used duplicate target sets to avoid clues. Hyman identified flaws in all 42 experiments, including statistical errors, poor documentation, and sensory leakage. Over half of the studies did not prevent sensory leakage, and all had at least one flaw. Hyman and Honorton agreed that these studies could not support the existence of psi.

Sensory leakage in Ganzfeld experiments included receivers hearing sounds from the sender’s room or seeing the sender’s fingerprints on the target. Hyman also studied autoganzfeld experiments and found a pattern suggesting visual clues might have influenced results. For example, frequently used video clips might have been easier to recognize. However, the parapsychology community did not take this seriously.

In 2010, Lance Storm, Patrizio Tressoldi, and Lorenzo Di Risio analyzed 29 Ganzfeld studies and found a 32.2% hit rate, which was statistically significant. However, Hyman argued that relying on meta-analysis (combining results) does not prove telepathy. He noted that the studies were not independently replicated and failed to provide evidence for telepathy. Storm et al. responded that the Ganzfeld design is reliable but called for more research. A 2016 study later examined questionable research practices in these experiments.

Twin telepathy, the belief that twins can communicate telepathically, is considered a myth in psychology. Psychologists Stephen Hupp and Jeremy Jewell said no experiments have shown evidence of telepathy between twins. They explained that twins often spend time together and share similar environments, so they may act similarly or predict each other’s actions.

In 1993, Susan Blackmore studied twin telepathy. In an experiment with six sets of twins, one acted as the sender and the other as the receiver. The sender tried to send information about objects, photos, or numbers. The results showed no evidence of telepathy.

Scientific reception

Many tests have been done to prove telepathy, but there is no scientific proof it exists. A group of experts asked by the United States National Research Council to study paranormal claims said that after 130 years of research, there is no scientific reason to believe in things like extrasensory perception or mental telepathy. Scientists say parapsychology is not a real science. There is no known way telepathy works. Mario Bunge, a philosopher and physicist, wrote that telepathy would go against the laws of science. He said sending signals without them fading over distance isn’t possible according to physics.

John Taylor, a physicist, said the experiments parapsychologists use to support telepathy have weak statistics and bad design. Scientists trying to repeat these experiments have failed. He also said their arguments use wrong ideas about physics and ignore important areas of physics.

Stuart Sutherland, a psychologist, said telepathy stories often come from people close to each other, like family members. They share a lot in common, so it’s likely they think the same thing at the same time. Graham Reed, an expert in anomalistic psychology, noted that telepathy experiments sometimes involve subjects seeing colored shapes. These are common hypnagogic images, not proof of telepathy.

Outside of parapsychology, telepathy is usually explained as fraud, self-deception, or mistakes, not a paranormal ability. Studies show other reasons like confirmation bias, expectancy bias, sensory leakage, subjective validation, and wishful thinking. Most popular psychic events, like mediumship, can be explained by non-paranormal methods such as cold reading. Magicians like Ian Rowland and Derren Brown have shown techniques similar to psychics but without claiming paranormal skills. They use methods like cold reading and hot reading.

Psychiatry

The idea of telepathy is similar to three medical conditions: delusions of thought insertion/removal and thought broadcasting. These similarities may help explain why someone might think they are experiencing telepathy. Thought insertion/removal is a symptom of a mental health condition called psychosis, which can occur in schizophrenia, schizoaffective disorder, or substance-induced psychosis. People with these conditions may wrongly believe that some of their thoughts are not their own, and that other entities, such as people, aliens, demons, or organizations, are placing thoughts in their minds (thought insertion). Some individuals may also feel that thoughts are being removed or erased from their minds (thought removal). People with schizophrenia who experience a type of alleged telepathy called thought broadcasting believe that their private thoughts are being shared with others without their permission. Along with other symptoms of psychosis, delusions related to thought insertion can often be lessened with antipsychotic medications. Mental health professionals and researchers believe that people with certain personality traits related to schizophrenia, such as schizotypal personality disorder, are more likely to believe in telepathy.