Tenhaeff, W(ilhelm) H(einrich) C(arl)(1894-1981)

Dutch parapsychologist, for some years director of the Parapsychology Institute of the State University of Utrecht, Netherlands (which he founded), now known as Parapsychological Division of the Psychological Laboratory. Tenhaeff was born on January 18, 1894, in Rotterdam, the Netherlands. He studied at the University of Utrecht (Ph.D. psychology, 1933). His doctoral thesis Paragnosie en infuhlen was the first on parapsychology in the Netherlands.

Tenhaeff had a long career as a respected parapsychologist. He was a lecturer on psychology (1932-53), lecturer on parapsychology (1933-53), professor of parapsychology, and director of the Parapsychology Institute, University of Utrecht (1953 on). He was founder (1928) and for many years editor (1928 on) of Tijdschrift voor Parapsychologie, the journal of the Studievereniging voor Psychical Research (the Dutch Society for Psychical Research). He served as secretary (1929-38) of the Dutch Society for Psychical Research prior to World War II and as an advisor afterward. In 1960 a number of leading parapsychologists withdrew from the society due to his autocratic disposition and established the rival Netherlandse Vereniging voor Parapsychologie.

Tenhaeff showed an interest in parapsychology from an early age, and conducted investigations and reported on psychometry, clairvoyance, precognition, unorthodox healing, the divining rod, and the structure of personality in sensitives. Through his career he lectured in many countries on parapsychological subjects, published numerous articles in Tijdschrift voor Parapsychologie and other journals, and wrote a number of books. In 1945 he commenced a long and detailed investigation of the clairvoyant Gerard Croiset. In the years after the 1960 break in the society, people began to look into his extraordinary claims for the psychic abilities of Croiset and discovered that he had been systematically doctoring data in his research. The fraud called his whole career into question. Because of his own popularity with the media and public, he was able to hold off the critics for some years, but eventually all of his colleagues acknowledged his fall. Tenhaeff died July 9, 1981, in the Netherlands; no major parapsychological journal carried an obituary.

Sources:

Berger, Arthur S., and Joyce Berger. The Encyclopedia of Parapsychology and Psychical Research. New York: Paragon House, 1991.

Hoebens, P. H. "Gerard Croiset and Professor Tenhaeff." In Science Confronts the Paranormal. Edited by Kenneth Frazier. Buffalo, N.Y.: Prometheus Books, 1986.

——. "Investigation of the Mozart of 'Psychic Sleuths.' " In Science Confronts the Paranormal, edited by Kenneth Frazier. Buffalo, N.Y.: Prometheus Books, 1986.

Tenhaeff, W. H. C. Beknopte Handleiding der "Psychical Research" (Short Textbook of Parapsychology). 3 vols. N.p., 1926.

——. Beschouwingen over Het Gebruik van Paranognosten (The Use of Sensitives for Police and Other Purposes). Utrecht: Erven J. Bijleveld, 1957.

——. Telepathie en Helderziendheid. English edition as Telepathy and Clairvoyance. C. Bertelsmann, 1962.