ESP stands for extrasensory perception or the perception of objects, thoughts, or events without the assistance of human senses. Extrasensory perceptions are collectively called psi phenomena. The definition of the ESP phenomenon lies outside the realm of scientific explanation, along with other related psychic abilities such as psychokinesis. Telepathy, the perception of the thoughts of another person, and clairvoyance, or remote perception, typically belong to the category of ESP. Telekinesis, the ability to move and manipulate objects with the power of the mind belongs to the category of pyschokinesis.
The study of both ESP and psychokinesis is parapsychology, which is the outgrowth of the Spiritualism movement in Great Britain and the US in the late 1800s. Prior to the 1930s, studies on paranormal abilities were highly subject to speculation and were often gathered through highly unscientific means. It was psychologist J.B. Rhine who first conducted the first series of rigorous, laboratory-based experiments testing for ESP, and it was said that J.B. Rhine was the first coin the term “extrasensory perception” to refer to perceptions not gathered through ordinary human senses. J.B. Rhine conducted hundreds and thousands of trials using Zener cards — a deck of cards containing psychic symbols like the circle, the five-pointed star, the square, a series of wavy lines, and the plus sign to detect extrasensory abilities in his subjects.
Since Rhine’s experiments, more sophisticated devices such as the Geiger counter and other have been developed to test and measure the psychic abilities of subjects.