Word spread amongst the Parisian upper class in the late 18th century:
A new man in town had a novel cure for pains, paralysis and numerous other maladies.
The charismatic German Dr Franz Anton Mesmer had discovered an invisible energy – he called it animal magnetism – allegedly flowing through all living organisms. Obstacles to this flow triggered illnesses. The problem could be corrected with some simple tools or manipulations.
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The patients – often female, upper bourgeois or aristocratic – exhibited strong reactions. A word cropped up for the phenomenon – they were mesmerized. They would moan, tremble and faint.
And recover their health.
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A variety of blind tests – examinations where patients don’t know what treatment they are receiving – demonstrated that the effect of Mesmer’s treatment in no way could be linked to magnetism. Patients were just as likely to improve from water that had not been “magnetized”. Or there would be no outcome despite ample applications of the prescribed manoeuvres directed toward the patient.
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Science’s first placebo-controlled blind study delivered two important revelations:
Animal magnetism does not seem to exist.
And individuals can in some mysterious way become healthier all on their own if they believe they are receiving effective treatment.