Parapsychological research: A tutorial review and critical appraisal

Abstract

Beginning in the 1850s, some eminent scientists such as Robert Hare, Alfred Russel Wallace, and Sir William Crookes investigated the claims of spiritualist mediums and believed that they had demonstrated scientifically the existence of psychic phenomena. Critics, without examining the evidence, dismissed the claims out of hand and charged the offending scientists with gross incompetence or with fraud. Encouraged by the work of these early psychical researchers, a group of scholars founded the Society for Psychical Research in London in 1882. In spite of this beginning, psychical research remained an amateur and uncoordinated set of activities until the publication of Rhine's Extra-Sensory Perception in 1934. The card-guessing experiments featured in Rhine's book became the model for experimental parapsychology for the next 40 years. Since the 1970s Rhine's paradigm has been replaced by a number of research programs such as remote viewing, the-Ganzfield experiment, and psychokinetic investigations using Random Event Generators. The present paper examines examples of what were considered, in their time, the best examples of scientific evidence for paranormal phenomena. Each generation of para-psychologists has set aside the work of earlier generations and offered up as sufficient scientific evidence the best work of its own day. As a result, parapsychology lacks not only lawful and replicable phenomena, but also a tradition of cumulative evidence. Two systematic evaluations of the best contemporary research programs in parapsychology revealed that the experiments departed from the minimal standards of adequate randomization of targets, appropriate use of statistical inference, and controls against sensory leakage. The historical survey in this paper suggests that the same themes and inadequacies that haunted the very earliest investigations still characterize contemporary parapsychological research. Both proponents and critics throughout the 130 years of the controversy over psychical research, have deviated greatly from those standards of fair-play and rationality that we would like to believe characterizes the best scientific arguments. Some encouraging signs for progress towards resolving some of the issues raised by the controversy have recently appeared. The criticism of the parapsychological claims is becoming more informed and constructive. Many younger parapsychologists have been working for higher standards within their field. The best lines of systematic research in parapsychology are not of sufficient quality to be put before the scrutiny of the rest of the scientific community. However, with the recent increase in constructive criticism and with the growing awareness within the parapsychological community that it needs to specify minimal standards and set its own house in order, there is hope that in the near future either the parapsychologists will fail to find evidence for psi or will be ready to challenge the scientific community with the sort of evidence that it cannot ignore.