Skepticism is a valuable habit that sharpens critical thinking, and the phrase 10 skeptics what captures the spirit of this roundup: ten remarkable investigators and the specific hoaxes they set out to dismantle. While many people cling to astonishing ideas—especially those concerning life after death—these ten figures devoted their careers to unmasking deception, from psychic charlatans to bogus spirit photography.
10 skeptics what: A Journey Through Debunking History
10 Milbourne Christopher
Milbourne Christopher rose to fame as a celebrated American magician in the mid‑20th century, even serving as president of the American Society of Magicians and performing for Franklin Roosevelt during the Great Depression.
Beyond his dazzling stage work, Christopher authored 24 books on magic and magicians, including a biography of his idol Harry Houdini. Yet, like many magicians, he turned his talents toward debunking those who claimed genuine psychic abilities.
He first made headlines as a skeptic when he exposed Uri Geller and other self‑styled psychics as frauds, revealing that their feats were merely clever illusion tricks. He detailed these findings in his 1975 tome Mediums, Mystics and the Occult.
Christopher’s critiques of psychic phenomena were generally scholarly rather than personal attacks on individual mediums, preferring a measured, academic tone.
He also investigated the infamous Enfield poltergeist case, concluding that the disturbances were the work of a mischievous child—a “little girl who wanted to cause trouble and who was very, very clever.”
9 Tony Cornell
Tony Cornell was a British parapsychologist who, together with colleagues, led the Cambridge University Society for Psychical Research. Over a fifty‑year career, he probed ghosts, hauntings, and related phenomena, ultimately concluding that such experiences are usually generated unconsciously by the observers themselves.
In the 1980s, Cornell and fellow researchers Alan Gauld and Howard Wilkinson built a device called the SPIDER (Spontaneous Psychological Incident Recorder) to monitor alleged paranormal activity. Of the roughly 800 investigations he conducted, only about 20 % proved difficult to explain, and nearly all showed no evidence of genuine paranormal forces.
One of his most playful experiments occurred in 1959 when he disguised himself as a ghost and walked across the front of a movie‑theater screen. When asked afterward, a surprising 32 % of the audience claimed they had not noticed the apparition.
8 Joseph Dunninger
Joseph Dunninger, an American magician whose voice was said to be “more recognizable than that of the president,” pioneered radio and television appearances long before many of his peers ventured into broadcast media.
He harbored a deep disdain for fraud, especially mediums, and dedicated much of his career to exposing their deceptions. Dunninger attended over a thousand séances, and he famously offered a $10,000 reward to any medium who could reveal the secret messages he had left for Thomas Edison, Harry Houdini, and Sir Arthur Conan Doyle before their deaths—no one ever claimed the prize.
7 Albert Moll
Born in the 19th century, German psychiatrist Albert Moll co‑founded modern sexology and championed hypnotism. Yet he is perhaps best remembered for his skeptical work, particularly his battles with medium Maria Vollhardt.
In a 1925 trial, Moll faced defamation accusations after labeling Vollhardt’s performances as “trick, manipulation, and farce.” He was ultimately acquitted, and he spent much of his life exposing the methods used by mediums and occult practitioners.
Moll authored detailed articles and books outlining the techniques fraudsters employed, while also acknowledging that rational individuals could become “hypnotized” by the atmosphere of seance rooms.
6 Joseph Jastrow
U.S. psychologist Joseph Jastrow gained fame for his inventions, most notably the Jastrow illusion, where two identical shapes appear different due to their arrangement. He also pioneered anomalistic psychology, a field that examines alleged paranormal activity while assuming no supernatural basis.
Jastrow and his colleagues investigated notable cases such as the Spiritualist Sir Oliver Lodge and the purportedly blind and deaf girl Willetta Higgins, ultimately proving that Higgins was neither fully blind nor deaf.
His frustration with frauds inspired a short 1945 poem: “There’s a sucker born every minute. Barnum said it; there’s sad truth in it. What burns me up, and turns me sour is that a crook is born every hour.”
5 Carlos Maria de Heredia
Carlos Maria de Heredia, known as Father de Heredia, was a Jesuit priest who vehemently opposed spiritism—a belief system distinct from spiritualism, positing that souls inhabit multiple bodies over time to achieve advancement.
He also mastered magic, a skill that proved invaluable when challenging “spirit hands”—wax‑like appendages alleged to be produced by ghosts. In a Popular Mechanics article, Heredia demonstrated that these “spirit hands” were simply rubber gloves filled with water, dipped in hot wax, and cooled, with the fraud simply removing the waxed glove after the trick.
Heredia further showcased his debunking prowess by staging a fake seance attended by over 500 people, easily fooling many of the participants.
4 Martin Gardner
Martin Gardner, a 20th‑century American author, was celebrated for his scientific and mathematical contributions as well as his skeptical activism. Over his prolific career, he authored more than 70 books, with the most renowned being Fads and Fallacies in the Name of Science, which catalogued hoaxes masquerading as legitimate science.
In 1976, Gardner co‑founded the Committee for the Scientific Investigation of Claims of the Paranormal (now the Committee for Skeptical Inquiry) alongside Carl Sagan, Isaac Asimov, and others. He contributed regularly to the group’s journal and wrote columns for Scientific American.
Gardner famously asserted, “Debunking bad science should be a constant obligation of the science community, even if it takes time away from serious research or seems to be a losing battle.”
3 Chung Ling Soo
Chung Ling Soo, the stage name of American magician William Ellsworth Robinson, fashioned himself after a famed Chinese illusionist and was a devoted Spiritualist. His spiritual convictions motivated him to expose mediums who employed deceptive devices.
He authored Spirit Slate Writing and Kindred Phenomena,” a treatise on the slate‑writing trick, where a “spirit” seemingly writes messages with chalk. He also performed a daring stunt called “Condemned to Death by the Boxers,” in which assistants dressed as boxers pretended to shoot him.
Tragically, on March 23 1918, a mishandled gun during this act discharged a real bullet, striking Soo in the chest. His final words were “Oh my God. Something’s happened. Lower the curtain,” marking the first public moment he spoke English after maintaining his Chinese persona.
2 David Abbott
American magician David Abbott gained fame for inventing tricks such as the floating ball and the talking tea kettle. He also ardently opposed mediums, penning works like Behind the Scenes with the Mediums, widely regarded as a premier exposé of fraudulent spiritual practices.
His most notable triumph involved the Bangs Sisters, a Chicago duo who claimed they could compel spirits to paint portraits of the deceased. Abbott discovered that the “sealed” envelopes containing photographs of the dead were opened beforehand, allowing the sisters to paint the likenesses the night before the séance.
Following Abbott’s revelations, the Bangs Sisters’ business quickly collapsed, especially as other magicians began demonstrating the trick publicly.
1 Eric Dingwall
Eric Dingwall, a respected British anthropologist, became best known for his relentless efforts to unmask mediums as frauds. In 1927, he published How to Go to a Medium, a practical guide for investigators seeking to expose deceptive practices.
The guide featured a “box of necessities,” including luminous pins for spotting a medium’s location in darkness and cotton thread for detecting any subtle movements. Dingwall preferred anonymity, avoiding the spotlight unlike his rival Harry Price.
His investigations into American medium Mina “Margery” Crandon sparked controversy, as he was accused of demanding she disrobe completely during his first visit. Crandon alleged this occurred repeatedly, and Dingwall hypothesized that a “spirit hand” was concealed within her vagina throughout the séances.