In addition to being the focus of corporate machinations, the Ouija board has also been invoked in many legal cases and has been featured in pop culture throughout the 20th century. But how does it work, psychologically speaking?
Research:

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Goodman, Edgar. “Pedigree of the ‘Witch Board.’” Omaha Daily News. June 13, 1920. https://www.newspapers.com/image/738037975/?terms=%22Fuld%20vs.%20Fuld%22&match=1
“Charge of Witch Hunting Enters Assault Case – Indian Woman is Accused of Attack With Hammer.” The Buffalo News. Oct. 26, 1932. https://www.newspapers.com/image/838894818/?terms=%22lila%20Jimerson%22&match=1
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Cassie, Ron. “Not Dead Yet.” Baltimore Mgazine. https://www.baltimoremagazine.com/section/artsentertainment/the-dark-and-fascinating-history-of-the-ouija-board-baltimore-origins/
“OUIJA!” The Norfolk Landmark. January 29, 1891. https://www.newspapers.com/image/604944772/?terms=ouija&match=1&clipping_id=99064762
“The New ‘Planchet.’” Chicago Tribune. April 3, 1886. https://www.newspapers.com/image/349738032/?terms=%22talking%20board%22&match=1&clipping_id=99068585
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“True Stories of the Supernatural, Told by Readers of the Sun.” The Baltimore Sun. February 14, 1909. https://www.newspapers.com/image/371064146/?terms=ouija&match=1
“Lie is Passed to Ouija, and By a Woman!” Chicago Tribune. Jan. 25, 1921. https://www.newspapers.com/image/355093958/?terms=ouija&match=1
Connoly, James P. “Ouija board boom on? Yes, Says Ouija Board.” Baltimore Evening Sun. May 18, 1944. https://www.newspapers.com/image/369642710/
“William Fuld Made $1,000,000 on Ouija Board But Has No Faith in It.” Baltimore Sun. July 4, 1920. https://www.newspapers.com/image/372844631/?terms=William%20Fuld&match=1&clipping_id=99076192
“Partners at Odds.” Baltimore Sun. Dec. 5, 1901. https://www.newspapers.com/image/365328757/?terms=%22William%20Fuld%22&match=1
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“The Ouija Craze.” Catoctin Clarion. January 22, 1891. https://www.newspapers.com/image/339101621/?terms=ouija&match=1&clipping_id=99064534
“Ouija-board Will Rejected by Supreme Court.” Newport Daily Express. Aug. 12, 1938. htt