Dr. J. B. Rhine initiated the scientific approach to parapsychology at Duke University in 1930. Zener cards were invented by Dr. Rhine, who is widely considered to be the “Father of Modern Parapsychology.” He named the cards after his research associate, Dr. Carl Zener. Dr. Rhine studied the phenomena now known as parapsychology at Duke University in Durham, North Carolina. Rhine coined the phrase “extrasensory perception” (ESP) to describe the apparent ability of some people to acquire information without the use of the physical senses. He also adopted the term “parapsychology” to distinguish his interests from mainstream psychology.
Dr. Rhine’s experiments involving telepathy, clairvoyance and precognition used specially designed cards, called Zener cards. This Zener deck was composed of 25 cards, with each card having one of five symbols- a cross, star, wavy lines, circle or a square. Under experimental conditions, test subjects would attempt to guess these cards. Out of each deck of 25 cards, 5 correct guesses were expected by chance. Using exact binomial probability calculations, it is possible to determine how “improbable” it would be to guess an excess number of cards correctly. In one set of experiments, 2400 total guesses were made, and an excess of 489 hits (correct guesses) were noted. The statistical probability of this outcome is equivalent to odds of 1,000,000 to 1 against chance, and thus showed evidence that “something occurred.”
What conclusions can be drawn from Rhine’s research program? By 1940, 33 experiments had been performed, involving almost one million trials, with protocols which rigorously excluded possible sensory clues (e.g., by introducing distance and/or barriers between sender and receiver, or by employing precognition protocols- i.e., where the target has not yet been selected at the time subjects make their responses). Twenty seven of the 33 studies produced statistically significant results; an exceptional record! Furthermore, positive results were not restricted to Rhine’s psychic lab. In the years following Rhine’s first publication, 33 independent replication experiments were conducted at different laboratories. Twenty of these were statistically significant.