Croiset Archive

Gerard Croiset (1909–1980), a world-famous Dutch clairvoyant and healer, carried on a voluminous correspondence with scientists, patients and others throughout his career. He also maintained detailed records of his professional activities. Much of this material, along with scientific reports and testimonials, is kept in the Johan Borgman Foundation in Utrecht, the Netherlands. This article describes aspects of his life and work in relation to the archive, and can be read together with the summary article Gerard Croiset.

Researchers interested in Croiset can contact the archive at the address given at the end of the article.


The Dutch psychic and healer Gerard Croiset, child of Jewish parents, was born on 10 March 1909 at Laren, in Walden. After his father left the family, Gerard was raised in foster homes and families. In 1933 he married Gerda ter Morsche (1910–1973). They started a grocery shop and had five children; the shop later went bankrupt.

Croiset became active in spiritist circles and started a practice as paranormal healer in Enschede, and later on in Utrecht. After World War II he became the best-known psychic in the Netherlands, with the help and supervision of parapsychologist WHC Tenhaeff. High-profile successes in missing person cases gradually gained him an international reputation.

Croiset remarried in 1976 to Adele Jonkman. He died suddenly in Utrecht on 20 July 1980.

Zorab, Tenhaeff and Bender

Before Croiset met Tenhaeff he attracted the interest of George Zorab, a parapsychologist and long-time secretary of the Dutch Society for Psychical Research (Zorab claimed to have corresponded frequently with him between 1936 and 1940 but none of this has survived). Zorab had a wide knowledge of the history of parapsychology and its precursors psychical research, spiritism, spiritualism, and mesmerism. He was also acquainted with Tenhaeff. Relations between the three men changed over the years, as did their opinions on paranormal phenomena. By 1955 Tenhaeff and Zorab were increasingly in conflict; a final break occurred in 1960.

In his early life Zorab was involved in spiritistic circles and strongly defended the study of paranormal phenomena. Gradually he adopted a more sceptical attitude, especially towards Tenhaeff and Croiset: convinced at first of Croiset’s paranormal abilities, later he came to doubt them, and also the integrity of Tenhaeff. In terms of theory, Zorab’s early spiritistic ideas developed into animism and eventually philosophical materialism. In common with Soviet parapsychologists, he recognized the existence of paranormal phenomena but thought they could be explained entirely in physical terms. In his later years Zorab no longer believed in survival of death.

Croiset also ceased to believe in life after death, rejecting spiritistic views or declaring them irrelevant. Instead he held a mystical philosophy, derived from his paranormal and spiritual experiences and governed by The Light, an impersonal divine principle. For Croiset, someone who experiences intense spiritual happiness no longer has desires and attachments, and does not desire survival of bodily death.

Tenhaeff remained more or less convinced of spiritistic theories throughout his life. Nonetheless, he believed that the existing support for the spiritistic hypothesis was still inadequate proof for its scientific recognition. He believed parapsychology must first investigate animist explanations before considering spiritistic ones.

Tenhaeff often accompanied Croiset on his travels and both became well-known; the two men worked together intensely for decades. It appeared that Croiset derived legitimacy from his scientific work with Tenhaeff, while the latter became more well known through his work with his ‘star’ psychic. But archival documents show that Croiset and Tenhaeff certainly were not hand and glove: they were strong characters who struggled when their interests conflicted. Tenhaeff wrote:

I know that he did not like my criticism and this was a cause for the ambivalent attitude he had towards me. Although the negative side of his ambivalence towards me weakened over the years, one has to recognise that it never completely disappeared. More than once problems arose between us. But the drifting apart never lasted for long, we should add immediately.1

Tenhaeff frequently published his research with Croiset in the Tijdschrift voor Parapsychologie (Dutch Journal of Parapsychology), the journal of the Dutch SPR. Croiset also published about his psychic work in this journal.

Tenhaeff became friends with German parapsychologist Hans Bender, a leading German parapsychologist, and invited him to help research Croiset. However, despite their shared interests their approaches differed. Tenhaeff investigated psychics within the framework of depth psychology drawn from Jung, Janet and others, while Bender adopted a qualitative approach based on case studies and was open to the Rhinian paradigm of statistically processing experimental results.

Tenhaeff’s investigations into the psychology of psychics – and the psychological determination of paranormal impressions – demonstrated that these are often associated with unconscious complexes resulting from unprocessed emotional tensions, events and traumas. Tenhaeff considered his ‘principle of associative connections’ to be his most important discovery: paranormal impressions of a psychic are sometimes symbolically related to experiences that have happened in his or her life. For instance, Croiset clearly remembered a peach that was lying on the bedside table of his grandmother who was dying of cancer; in his subsequent work as a healer he knew that a patient had cancer if a peach appeared before his inner eyes.

From his first meeting with Croiset, Bender was impressed by the psychic’s personality and paranormal abilities. Feelings of sympathy developed between the two men. In his speech at the Croiset’s funeral, Bender described his paranormal abilities as being ‘embedded in a humanity coming from the heart, in an always benevolent consideration of other people’.2 Bender was especially impressed by Croiset’s critical self-evaluation – he knew his limits, never boasted of being infallible, and knew that his clairvoyant perception could often be distorted by imagination.

Bender experimented for many years with Croiset at his Institut für Psychologie und Grenzgebiete der Psychologie (IGPP) in Freiburg. Besides clairvoyance he was interested in Croiset’s work for the police; the archive contains some of Bender’s reports on Dutch missing person cases, made after the two men visited places in the Netherlands where the individuals had resided. Thirty-four letters from Bender to Croiset and nine from Croiset to Bender are found in the archive.

Archive Contents

Croiset was workaholic and invested much time and money keeping a daily record of all the different aspects of his work. The archive contains an enormous number of manuscripts and typescripts for his autobiography, along with written thoughts on philosophy and parapsychology, and reports on experiments, police cases and his work as a psychic healer. He used this material for his lectures and demonstrations in the Netherlands and abroad.

For the purposes of parapsychological research, Croiset recorded telephone calls of clients that were later turned into verbatim typewritten reports by his assistants. On one occasion he received a call from Prince Bernhard, the consort of Queen Juliana, summoning him to the royal palace at Soestdijk to search for a missing jewel.

The archive also contains thousands of articles about Croiset. These include newspaper articles on the discussion that arose in the Dutch parliament on attempts by Croiset and his son Gerard, also a healer, to alleviate the pain of Princess Armgard, Prince Bernhard’s dying mother (Bernhard had first approached Croiset, who after an initial visit to the princess decided that Gerard, who lived closer to her home, could provide better help).

Audio and Film

Along with written documents and audio tapes, the archive also contains photographs, 16mm film footage and VHS video material connected to Croiset’s cases. As early as 1950, Croiset started buying expensive reel-to-reel tape recorders and photo and film cameras. He arranged for reports of missing person cases he had worked on to be translated into French, German, English and Italian, so that they could be sent to foreign parapsychologists. These were accompanied by detailed photo reports, made by attaching his self-made photographs on large sheets of paper with additional captions and written comments.

In his book Ontmoetingen met Paragnosten (Meetings with Psychics),3 Tenhaeff writes that during the war, Croiset started to film his healing activities with patients suffering from poliomyelitis, which he continued for long periods to illustrate progress. A unique aspect of this are involuntary muscle movements in paralysed extremities shown by patients during Croiset’s healing activities. One film shows healing in a paralysed dog, indicating that suggestion was not the cause of improvements in human patients (this was filmed by Croiset’s son Henri, a professional photographer.)

In 1967 Croiset was approached by BBC documentary makers, also by others such as America’s ABC (1966), Italian RAI (1972), and the German ARD and ZDF broadcast companies. Many of these film and sound recordings are present in the archive.

Croiset the Author

Croiset recorded memories in the form of notes for his autobiography Croiset Paragnost (1977, in Dutch), which ran through four reprints within a few years. Notes not included were used for a second book Nagelaten Werk (Posthumous Work, 1988) eight years after his death. Some of these developed into philosophical reflections based on introspection and analysis of his paranormal and spiritual experiences; many such essays and articles are preserved in the archive, showing the connection between Croiset’s psychology, philosophy and religiosity. Topics include: dimensions, love, love your fellow creature, rest, healing by prayer, the Perfect, evolution, experience of desire, wish, composition, reflection of truth, in search of the truth, conscious being, good and evil, yin-yang sign, suffering humanity, the urge to act, unification, the Light, desire to get a notion of why the light is revealing to me, harmony and discord, God, the visible God, the echo of God, reverberation, resonance, believe, the attribute, Christ, creation, global knowledge, objective knowledge, subjective knowledge, religious knowledge, desire for self-knowledge, harmony between gross and fine substance, projection, reflection, the nebula, psychological composition, personality structure, process, and the elementals.

Croiset also recorded his thoughts as material for lectures in the Netherlands and abroad. He spoke on subjects such as objective clairvoyance, unconscious existence, precognition, the visible and the invisible God, and the feeling of being in direct connection with ‘It’. He lectured in churches, universities, adult education centres, and business associations, and held ‘experimentation evenings’, both in the Netherlands and abroad (he had his lectures translated into German so that he could read them in that language).

Croiset’s articles appeared in Het Tijdschrift voor Parapsychologie, in De Paranormal Genezer (The Paranormal Healer, the journal of the Dutch Federation of Paranormal and Natural healers), and in NWP-Orgaan (journal of the NWP,4 the Dutch working group for the application of paranormal abilities, of which Croiset was long-time president). In these journals Croiset wrote about the development of his paranormal experiences and his philosophy of life. Some were translated: the article ‘Het Licht’ (The Light) appeared in German as ‘Das Licht’ (1975), published in Imago Mundi by Andreas Resch.


An extensive correspondence with persons from all over the world has been preserved in the archive. Croiset only spoke Dutch and a little German: translators took care of his correspondence and represented him abroad. Rudolf Sieber was his interpreter for German, Rita Reynders for English, and Maria Gobbo for Italian. Sieber and Gobbo lived in Germany (Emmerich) and Italy (Milan), respectively. Sieber prepared Croiset’s first tours in Germany, accompanying Croiset at universities and adult education centres. Gobbo invited Croiset to work as a paranormal healer in Milan.

Most letters in the archive concern Croiset’s work as a healer and contacts with patients and doctors. Besides family members, there is also correspondence with prominent politicians, lawyers, and police and military officers.

Contacts with Dutch celebrities are found in the archive, including soprano Elly Ameling, entrepreneur Albert Heijn, journalist and TV director Carel Enkelaar, filmmaker Louis van Gasteren, journalist Willem Oltmans,5 journalist Bibeb (Elisabeth Maria Lampe-Soutberg) and writer-poet Simon Vinkenoog. The psychic also received letters from Duchess De la Rochefoucauld and the Countess De Saint-Exupéry. A visiting card of the Romanian writer Vintila Horia suggests that he may have visited Croiset.

Croiset also corresponded with dozens of international parapsychologists and board members of parapsychological associations, including Martin Johnson at Utrecht University’s Parapsychological Laboratory, who once carried out an experiment with Croiset.6 (See below.)

Publications on Croiset

Research papers by Tenhaeff on Croiset’s criminal investigations and healing activities appeared in the Tijdschrift voor Parapsychologie throughout the period 1947–1980. The 1952 issue alone contains three articles about him and others in which he is mentioned. In the period 1947–1970, articles about the use of psychics in police investigations, especially Croiset, were published in the official Dutch police journal by Tenhaeff and police officers.

Numerous articles on Croiset were published in the mainstream media the Netherlands and abroad, notably in Germany following a lecture tour in 1951. Scientific articles on experiments with Croiset were published in the Zeitschrift für Psychologie und Grenzgebiete der Psychologie by Bender and colleagues at Freiburg University. Articles by Jule Einsenbud, Lawrence LeShan, Aristide H Esser and Piet Hein Hoebens appeared in English language journals such as Journal of the Society for Psychical Research and Journal of the American Society for Psychical Research.

The archive contains articles on Croiset in twenty different languages including Japanese, Turkish, Arab, Hebrew and Russian. Those in English increased considerably after the publication in 1964 of Croiset the Clairvoyant by American journalist Jack Harrison Pollack. Books on Croiset were published in Dutch, German, English, French, Italian, and Spanish, mainly translations of Pollack’s book.

Parts of Anton Neuhäusler’s book Telepathie Hellsehen Preakognition (1957) are devoted to Croiset. Neuhäusler, a philosophy professor from Munich, corresponded with Croiset over many years and in 1955 invited him to perform a chair test (see below) at his institute. He was visited by German writer Gustav Regler, who dedicated a chapter of his last book Helseher und Charlatane to a description of credible experiences with the psychic (this has not yet appeared in print and awaits publication by the University of Saarland). In his biography of Hans Bender Suche im Grenzenlosen (1993), Elmar R Gruber, staff member of the IGPP, wrote about Croiset’s work with Bender in Freiburg.

Croiset’s friend Carel Enkelaar published Het Geval Croiset (The Croiset Case) in 1959. In the following years, several Dutch authors dedicated one or more book chapters to him: WHC Tenhaeff in Ontmoetingen met paragnosten (Meetings with Psychics, 1979), GL Durlacher in Niet Verstaan (No Understanding, 1995)) and FGA Woudstra in Duikverhalen: Belevenissen van de Mens Onder de Zeespiegel (Diving Stories: Experiences of Men Below Sea Level, 1968). (See below.)

Gerard Durlacher, a well-known Dutch writer and sociologist who survived the Nazi concentration camps, describes in his autobiographical story Sonja having met Croiset as a medical student shortly after World War II: Croiset was at the medical faculty of Utrecht University and gave an impressive demonstration of his treatment of polio patients. (Croiset had survived the war himself by means of a forged document that stated that he was not of Jewish heritage.) In conversation, Croiset predicted that Durlacher would receive two brown envelopes in the near future. A few days later Durlacher received two letters in brown envelopes from the Red Cross stating that his mother had died at Stutthof concentration camp in February 1945 and his father at Bergen-Belsen, in March 1945.

In Duikverhalen, FGA Woudstra, a professional diver, described his cooperation with Croiset in his search for drowned persons. An employee of KLM (Dutch Royal Airlines) had drowned while diving with self-made oxygen apparatus; he was found after Croiset indicated precisely the location and depth where the body would be discovered. The second victim was an eight-year-old girl that fell through the ice. When a two-day search failed to reveal the body, Croiset was consulted by telephone. He responded as follows:

You are speaking with Croiset. I know you are searching for a girl that drowned the day before yesterday. You are calling now from a house not far from the dike. If you walk towards the dike in the direction of an excavator you will see two inlets. At the end of the second inlet you make an angle of 50 degrees on the axis of the dike. You must dive approximately 35 metres out from that point. You will not find the child immediately. She is covered completely with a layer of sand. Only the little boot with the skate attached protrudes above the sand. The wall of earth collapsed.

A hole was cut in the ice at the place indicated by the psychic. Within five minutes a diver came up with the little skate, and the body was found.

Demonstrations and Experiments

Letters and photographs contained in the archive show that Croiset performed experiments in psychokinesis (PK) and mental influence on living organisms, either at universities or with scientists associated with these universities. He also had professiona contacts with parapsychologists, psychics, and well-known board members of psychical research societies in different countries. An incomplete list is given below:

Robert Amadou, Société Française de Parapsychologie

Hans Bender, Freiburg

J Bendien

Dick Bierman, Amsterdam

G de Boni, Verona

JG van Busschbach

Rosemary Brown

P Cassoli, Bologna

J Dierkens, Mons

AH Esser and NS Kline, New York

Jule Eisenbud, Denver

J Gelan and J Renson, Diepenbeek

Jarl Ingmar Fahler, Finnish Society for Psychical Research

Dr Hougardy, Belgian Committee for Scientific Investigation of Purported Paranormal Phenomena

Martin Johnson, Utrecht

W Kugel, Berlin

J Kistemaker, Amsterdam

Margot Klausner, Israel Society for Parapsychology

Matthew Manning

CA Meier and A Neuhäusler, Munich

Karlis Osis, American Society for Psychical Research

B Pomeranz, Toronto

H van Praag, Utrecht

Sybo A Schouten, Utrecht

WHC Tenhaeff, Utrecht

WH Uphoffm, University of Wisconsin

J Weima, Nijmegen

A Resch, Innsbruck

E Servadio, Rome

Berthold Eric Schwarz

M Valkhoff, South African Society for Psychical Research

George Zorab, Dutch Society for Psychical Research&&&

Croiset worked with hitherto unknown scientists at Santa Barbara in California (USBC), and at Stanford (probably Harold E Puthoff and Russell Targ).7

Croiset was known for his ‘chair tests’, which he performed for parapsychological experiments at universities and for TV and radio documentaries, and as demonstrations throughout the country. But he also participated in experiments designed by serious scientists. One series – performed at Enzypharm, a pharmaceutical company in Soest in 1969-1970 – investigated mental influence on the structure and light permeability of substances, and on the development of cancer cells in mice.8 With his friend, psychic Warner Tholen,9 Croiset also participated in experiments at the University of Diepenbeek (now Hasselt University), Belgium, in 1979-1980, performed by chemist Jan Gelan, which are described in documents, reports, photographs and films preserved in the archive.  In one such experiment, the psychics attempted to mentally change the structure of a chemical fluid, resulting in a changed NMR-spectroscopic signal. The experimental scientists of both Enzypharm and Diepenbeek concluded that Croiset had brought about inexplicable effects.

Scientists also performed physical experiments with Croiset at his home in Utrecht and at the FOM institute Rijnhuizen, Nieuwegein, between October 1976 and March 1977, using devices such as coils, oscillographs and Faraday cages. These were preliminary investigations to detect psychokinetic&&& effects and standardise measurement methods. Some data were suggestive of paranormal influences, but the authors conclude that mistakes were made that precluded fool-proof measurements and a clear conclusion.10

The archive contains 216 reports of (or references to) chair experiments during the period 1946–1980. Of these, 169 were carried out throughout the Netherlands (except Zeeland). The 47 foreign chair experiments were carried out in Germany (24), Belgium (6), the United States (5), Italy (4), Switzerland (4), Japan (2), France (1) and Denmark (1).

Chair experiments were often performed during evening meetings before a large public, where Croiset also gave a lecture and showed films of his work. He organized these demonstrations – informative and recreational rather than scientific – to raise money for the Stichting 1940–1945 (Foundation 1940–1945) established to support surviving relatives of resistance fighters. Tenhaeff or some other parapsychologist might be present, but control measures were insufficient and the subsequent reports lacked the detail necessary to provide scientific value.  

Police Cases

Croiset was often asked by police officials to co-operate in criminal investigations. Sometimes he appeared in court as expert witness in trials against allegedly fake healers, or as witness in a murder case in which he had assisted the police in finding the culprit. The police might ask him to help track down murderers and arsonists, or missing persons who had been kidnapped, killed, or run away from home. At other times he was asked to find someone who had caused a fatal accident. Occasionally, he was approached to help individuals recover stolen property, but he usually declined out of an intense dislike of financial matters resulting from the anarchist and socialist principles his father had instilled in the family.

From the number of missing person cases mentioned by Tenhaeff and Croiset in letters and interviews, we can infer that many reports have been lost. Archive contents refer to 671 missing person cases (303 Dutch and 368 foreign) that occurred between 1930 and 1980. Most of the Dutch cases were in the province of South-Holland (71: 24%), followed by North-Holland (51: 17%), Utrecht and Gelderland (35 each: 11.5%) and Overijssel (27: 9%). The locations of twelve cases (4%) are unclear.

Croiset was involved in missing person cases in 44 foreign countries including remote locations in Madagascar, Iceland, Burma, New Zealand and Congo (Zaire). Most of the international cases concerned missing persons in Germany (68: 18.5%), United States (48: 13.5%), Italy (27: 7.5%), France (22: 6%), and Great Britain (21: 5.5%). In some cases, the only surviving documentation is testimony in the popular press, which is sometimes tendentious or biased, but occasionally gives a good description of the local colour.

Croiset won international fame for successfully tracing missing persons. During his visit to Tokyo in May 1976, he was filmed by Japanese TV while successfully tracing the body of a missing girl, Miwa, who had drowned.11 This case received worldwide media attention. Alternative sceptical explanations were recognized to be far-fetched: for instance, if the psychic had staged the event, he would have required accomplices to release the body to the surface at the very moment the police arrived at the spot indicated by Croiset. (See Kramer (1990) for a thorough analysis.)12


Croiset received 80 to 120 patients per day in his practice at the Willem de Zwijgerstraat, Utrecht. In the 1950s he also practised two days a week in Enschede. During stays in Germany and Italy he treated patients in Emmerich and Milan, respectively. Close contact with patients was not always necessary; according to letters in the archive Croiset achieved good results healing patients at a distance. Besides 581 Dutch patients who consulted him directly, there are documents relating to a further 174 patients who were officially referred to him by medical doctors and specialists, both in the Netherlands and foreign countries. A further 142 patients came from countries other than the Netherlands.

Remarkably, medical doctors referred patients to Croiset not only for treatment, but for medical diagnoses and advice as well. In a letter dated 5 February 1977, general practitioner C van der Linde from Alkmaar requested an advisory appointment for his patient Mrs L Poley-Pikaar, who suffered from migraine. After meeting the patient, Croiset concluded that she had a narrowed blood vessel in the right rear side of the brain. Van der Linde wrote again on 18 December 1978:

As a result of your diagnosis I referred her to a neurologist for an arteriography, and he called me afterwards, being very surprised: ‘damn there is a closing of the vessel just as Croiset told you’. Although treatment is not possible, Mrs. Poley is so reassured that she has no brain tumour, that she can now live with almost no medicine, and functions better in her family!

The 581 Dutch patients come from all the provinces. Most patients live in the province of Utrecht (99: 17%), Overijssel (97: 16%), North Holland (94: 17%), South Holland (89: 15%), Gelderland (76: 13%), and North Brabant (37: 6%).

Patients of Croiset came from 23 countries, mostly Norway (31: 21.5%), Germany (27: 19%), Belgium (20: 14%), Italy (18: 12.5%), Switzerland (8: 5.5%), and the United States (7: 5%).

The 581 Dutch patients asked for treatment for 94 different complaints, ailments and syndromes, including: pain (57: 11%), psychological problems such as anxiety, depression, nervous complaints, feelings of restraint, grief (41: 8%), walking difficulties, leg complaints, stiffness (31: 6%), paralysis other than poliomyelitis (24: 4.5%), poliomyelitis (22: 4%), eye disease and blindness (17: 3%), developmental delay (15: 3%), muscle disease, including Guillain-Barre syndrome, and muscular dystrophy (13: 2%), inflammation (13: 2.5%), fatigue, exhaustion, weakness (13: 2.5%), ear disease and hearing problems (13: 2.5%), rheumatism, arthritis and arthrosis (12: 2.5%).

Forty-seven ailments can be found in the data of 174 patients that were referred to Croiset by medical doctors for treatment, diagnosis or advice, including: pain complaints (30: 19%), psychological complaints and disorders, neurasthenia, anxiety and depression, hallucinations (20: 12.5%), stomach complaints (8: 5%), paralysis other than polio, (7: 4%), leg and walking problems (5: 3%), fatigue or despondency (5: 3%), migraine (5: 3%), insomnia (5: 3%), asthma and bronchitis (5: 3%), rheumatism and arthrosis (5: 3%), stomach and intestinal complaints (5: 3.13%), and multiple sclerosis (4: 2.5%).

Among the 142 foreign patients, 47 illnesses or ailments were documented. The most common were: patients with paralysis including polio (11%), walking problems and arthritis in the legs (11%), balance disorders, dizziness, weakness, lethargy, and fatigue (9: 7%), pain complaints (9: 7%), stress, tenseness and nervousness (8: 6%), psychological problems, mood disorders, emotional problems, anxiety and depression (4.5%), respiratory problems and bronchitis (3%), back problems (3%), skin problems, psoriasis and eczema (3%), eye complaints and cataract, (2.5%), speech disorders (2.5%), and stomach complaints (2.5%). 

Poliomyelitis patients existed in high numbers during Croiset’s early years as a paranormal healer, when mainstream medicine could still not offer an effective treatment (according to Tenhaeff, Croiset was most successful with these). The same applied to persons with general locomotive problems resulting from old age, rheumatism or arthrosis. Croiset’s healing activities with these patients became well known by word of mouth.13

Physicians mainly referred patients with ‘unclear’ pain complaints, and psychosomatic and psychological ailments that had not responded well to their treatments. Lacking options, some doctors probably thought ‘it doesn’t hurt to try’. Croiset for his part referred many of his patients to medical doctors and co-operated with them as best he could. A mutual trust developed.

Personal Qualities

Croiset permitted dozens of scientists from different countries to test his paranormal abilities. The documents, reports and articles in the archive give the impression that he was successful in his healing and police work and as a subject in parapsychological experiments. Most clients of his healing practice were satisfied and totally convinced of his integrity and altruism. The same applies to almost all parapsychologists who ever worked with him; a letter from Zorab and one from Neuhäusler mention the possibility of cheating but offer no evidence of it. Clients visited his practice seeking help for a variety of ailments over many years.

Croiset attended a humanistic school for some time during his childhood. In autobiographical documents he writes that his life-long need to help other people stems from this period. When patients were unable to pay, he treated them for free. Croiset did not charge scientists for participating in their experiments.

Although Croiset had proven his paranormal skills in numerous experiments, part of his success as a healer was undoubtedly due to common factors such as empathy, warmth and authenticity, psychological characteristics that are very helpful in psychotherapy and welfare work. In his long career Croiset had learned to handle his paranormal abilities with optimal results. Tenhaeff had urged him to be self-critical and appreciate the value of introspection. In a conversation with Tenhaeff Croiset described what he had learned:

You draw my attention to all sorts of things that previously escaped my attention. You taught me to pay attention to myself and realise what I see and why I see it. I started to contemplate various things which have taught me to differentiate between important and trivial, incidental matters. ... Before, I often drew wrong conclusions from the images that appeared to me. Therefore I learned to restrict my utterances to what I see. I do not want to say that I always succeed in this. The mistake of a wrong interpretation, that is so dangerous in consults for police purposes still sometimes occurs, but less than in the past.14

Croiset repeatedly wrote of his awareness that Croiset the psychic could be obstructed by Croiset the man, and of the need to remain neutral, particularly when working on police cases, ensuring that his subjectivity, and inhibitions originating in the past, did not interfere with paranormal impressions. After one failed attempt he noted:

Because of my egocentric attitude I was not conscious enough of my responsibility towards society. ... A person or case must be ripe to be eligible for a consult by a psychic. ... Paranormal phenomena are subject to their own laws. When we consciously or unconsciously sin against these laws, all kinds of interferences arise.15

Croiset seemed to believe his success was partly determined by an attitude of patience, receptivity and openness, and that the paranormal belongs to a class of phenomena that cannot be directly evoked. Various aspects of human existence may befall us – such as happiness, love, authenticity, friendship, intimacy, personal convictions and some social phenomena – but they cannot be planned or forced. Philosopher Koo van der Wal calls them ‘additive phenomena’, that arise spontaneously but resist attempts to elicit them at will; he believes that paranormal phenomena belong to this category.16 Hans Bender would have agreed. In his experiments with Croiset, he determined that the psychic performed better in playful rather than serious circumstances, concluding ‘that the purposefully used prediction had to surrender to human destiny’.17


The sheer scale of the archive provides an unmatched view of the personality, life, thoughts and work of an exceptional psychic. Croiset spared no trouble or expense to record all aspects of his work during his entire career. In that sense it may be described as rich.

However, in another sense the archive’s value is limited. The accuracy of the reports varies and the documentation of important police cases and experiments is unfortunately for the most part inadequate. These limitations make it hard to attempt a final evaluation, or to wholly rescue Croiset’s reputation from the damage posthumously inflicted by sceptics, notably Piet Hein Hoebens.18

But none of this need not weaken the conclusion that he was successful, given the enthusiastic testimonies of most of the patients, parapsychologists and police officers from many corners in the world whom he worked with for years, to which archive documents bear witness.

Johan Borgman Foundation

The Croiset archive is housed at:

Stichting Het Johan Borgman Fonds (The Johan Borgman Foundation)
PO Box 40

Bunnik 3980 CA 

The Netherlands
[email protected]

Maurice van Luijtelaar and Wim Kramer


Bender, H. (1980). Worte des Abschieds für Gerard Croiset. Zeitschrift für Parapsychologie und Grenzgebiete der Psychologie 22, 84.

Bierman, D. (2015). Parapsychological Association – Verslag van de hoogtepunten en dieptepunten van de 2015 conventie. Tijdschrift voor Parapsychologie en Bewustzijnsverschijnselen 82/2, 24.

Durlacher, G.L. (1998). Niet verstaan, chapterSonja”. In Verzameld Werk, Amsterdam: Meulenhoff, 438-73.

Eisenbud, J. (1973). A transatlantic experiment in precognition with Gerard Croiset. Journal of the American Society for Psychical Research 67/1, 1-25.

Enkelaar, C. (1955). Het Geval Croiset. Baarn: Het Wereldvenster.

Croiset, G. (1975). Das Licht. In Mystik, ed. by A. Resch, 253-65. Imago Mundi [offprint].

Croiset, G. (1976). Voorlopig verslag van Gerard Croiset over zijn ervaringen in Japan. Tijdschrift voor Parapsychologie 2, 63-69.

Croiset, G. (1982, 1977). Croiset Paragnost. Naarden: Strengholt’s Boeken.

Croiset, G. (1988). Nagelaten Werk. Naarden: Strengholt’s Boeken.

Elster, J. (1983). Sour Grapes: Studies in the Subversion of Rationality. Cambridge: Cambridge University Press.

Esser, A.H. & LeShan, L. (1969). Case history: A transatlantic chair test. Journal of the Society for Psychical Research 45, 169-71.

Gerster, G. (Ed.) (1956). Positive Kritik des Aberglaubens. Eine Stunde mit Prof. Dr. Hans Bender. In Aus der Werkstatt des Wissens. 1, Eine Stunde mit ... C.G. Jung, Adolf Portmann, Leopold Szondi, Karl v. Frisch, Hans Bender, Tadeus Reichstein, Max Lüscher, Walter Baade, Walter Mörikofer, K. Graf v. Dürckheim, Paul Scherrer, Alfred Schifferli, Alexander Mitscherlich, Hugo Krayenbühl, J.H. Schultz. Frankfurt a.M.: Ullstein, 65-82.

Gruber, E.R. (1993). Suche im Grenzenlosen. Cologne: Verlag Kiepenheuer & Witsch.

Hoebens, P.H. (1986). Comparisons of reports of the Denver chair test: A critical examination of the methods of WHC Tenhaeff. Journal of the Society for Psychical Research 53, 311-24.

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  • 1. Tenhaeff (1980).
  • 2. Bender (1980), 84.
  • 3. Tenhaeff (1979), 135.
  • 4. Nederlandse Werkgroep voor Toepassing van Paranormale Begaafdheid.
  • 5. An English translation of Luijtelaar (2016), 20-27.
  • 6. Roll and Williams (2008). Croiset obtained a significant score (p < 0.01) in the experiment that the young Johnson carried out with him. See Gerth van Zanten (1972). The archive contains film clips of the experiment.
  • 7. Croiset had difficulty remembering foreign names, and in his autobiographical notes describes the scientists he worked with as laser scientists. This would have occurred 16-19 March 1973. In his memoirs, Forbidden Science (vol II, 184), Jacques Vallee mentions a visit by Croiset to his colleagues at Stanford/Palo Alto.
  • 8. Invloeden van G. Croiset (Influences by G. Croiset). Invloeden van G. Croiset II (Influences by G. Croiset II). Tenhaeff (n.d.) Orientation researches with healers.
  • 9. Parergy-Experiments with Croiset-Tholen (simultaneously) (n.d.). Kramer and Luijtelaar (2016) describe how, as early as 1951, Croiset cooperated with psychic Tholen in an experiment supervised by Tenhaeff.
  • 10. In Heide and Cool (1978). In 1976 J. Scheeren recorded Croiset’s EEG during various parapsychological experiments at the University of Nijmegen.
  • 11. Croiset (1976), 63-69.
  • 12. Kramer (1990), 76-83.
  • 13. Tenhaeff (1979), 196.
  • 14. Tenhaeff (1979), 205, 208.
  • 15. Croiset (1969), 61.
  • 16. Wal (1996), 106-114; also in notes of Wal’s lectures at De Wijsgerige Kring Eindhoven, 3 and 10 November 2015. Wal uses the Dutch word ‘toegiftverschijnselen’ for additive phenomena, which he says cannot be directly elicited but occur when we are occupied on other objectives, applying to paranormal phenomena Jon Elster’s (1983) concept of ‘states that are essentially by-products’. Some parapsychologists hold similar opinions. German parapsychologist Walter von Lucadou is convinced that attempts to use the paranormal in a pragmatic way may lead to paradoxes, and parapsychologist Dick Bierman in the Netherlands concludes ‘nature does not permit this.’Bierman (2015), 24.
  • 17. “...dass die Zweckhaft gewollte und eingesetzte Prophetie vor dem Geheimnis menschlichen Schicksals kapitulieren musste.“ Gerster (1956), 72.
  • 18. Hövelmann & Michels (2017).