ABSTRACT
From the beginning of scientific research in parapsychology in the 1880s, mediums and psychics have generated much interest. However, no means were then available to make objective assessments of the verbal impressions of psychics and mediums. Interpretation of the data was purely a subjective matter. During the 1930s, the first attempts were made to develop methods for quantitative, and later on statistical, evaluation of purportedly paranormally-obtained statements of mediums. The history of the development of these methods is primarily a matter of the discovery and elimination of possible sources of errors. As a result, today satisfactory methods are available. A very condensed overview is presented of all studies in which statements of mediums or psychics have been quantitatively evaluated. The main question asked in most of these studies was whether a significant number of correct statements deviated significantly from chance expectation. Another question, less often addressed, was whether psi ability is necessary to explain the correct statements. The present study indicates that the number of studies with significant positive results is rather small. Moreover, in most of these, one or more potential sources of error were present that might have influenced the outcome. It seems, therefore, that there is little reason to expect psychics to make correct statements about matters unknown at the time more often than would be expected by chance. An explanation is offered for the apparent successes of psychics in everyday-life consultations that takes into consideration the role of the client or sitter, which is generally underestimated. Extremely put, it is proposed that it is the client who makes the psychic. Nonetheless, under certain conditions, which are described, asking advice from a psychic can be meaningful.
