They claim that subjects who believe in parapsychological phenomena tend to do better on the tests, as do subjects who are given immediate feedback after each guess. Most scientists outside of the parapsychological field do not accept the existence of psychic phenomena, although some universities teach parapsychology courses and in 1985 a Chair of Parapsychology was established at Edinburgh University, funded in part by a bequest from the author Arthur Koestler. Parapsychological research has often been attacked by conventional scientists as fraudulent. Rhine himself once discovered that one of his senior researchers had been faking results, and dismissed him. A more serious charge is that parapsychologists are not well-enough trained to be able to tell when a subject is committing a fraud against them.
Parapsychologists claim that such fraud occurs only in an insignificant number of cases.
Other critics have charged that in many parapsychological research projects, statistical inferences have been made, experimental design has been shoddy, and data has been misread. A 1988 study by the National Research Council in the United States found that no scientific research conducted in the previous 130 years had proven the existence of parapsychological phenomena, although the council did find probabilistic anomalies in some experiments that could not readily be explained. Parapsychologists have countered that the study was unfair because the members of the study committee were prejudiced against parapsychology. A final criticism is that for phenomena such as extrasensory perception and psychokinesis to be true, fundamental physical laws would have to be broken. Some parapsychologists adopt the view that psychic phenomena are outside the realm of science, whereas others believe that breakthroughs in quantum physics may one day provide explanations for such phenomena.