Animal Magnetism

Franz Anton Mesmer, a Vienna-trained physician working in Paris from the 1770s, proposed that a single invisible fluid, which he called animal magnetism to distinguish it from ordinary mineral magnetism, pervaded the universe and connected all living bodies, and that disease resulted from blockages in this fluid's natural flow through the body, blockages a trained magnetizer could detect and clear. Mesmer's most famous treatment setting was the baquet, a large covered tub filled with iron filings, powdered glass and bottles of magnetized water, from which iron rods projected for patients, seated in a circle around it and often holding hands, to apply to their afflicted body parts, while Mesmer himself, dressed dramatically in lilac silk, moved among them making hand passes and using a wand or his own touch to direct the fluid.

Treatment frequently produced dramatic "crises," convulsions, weeping, laughter or fainting, which Mesmer and his followers interpreted as the therapeutic climax of the fluid's blockage being released, after which patients often reported genuine relief from their symptoms. Mesmer's clinic became immensely fashionable in pre-revolutionary Paris, drawing aristocratic clients and considerable controversy among the city's established medical faculty, who viewed his claims and his showmanship with open suspicion well before any formal investigation was convened.

In 1784, King Louis XVI convened a Royal Commission to investigate animal magnetism, bringing together some of the most eminent scientists in France, including Benjamin Franklin, then American minister to France, the chemist Antoine Lavoisier, and the physician Joseph-Ignace Guillotin, under the astronomer Jean Sylvain Bailly. The commission, working with Mesmer's own former student Charles d'Eslon since Mesmer himself refused to fully cooperate, designed and ran a series of genuinely innovative blinded experiments, including directing subjects to a supposedly magnetized tree while observing that reported effects occurred regardless of whether the tree had actually been magnetized, among the earliest documented uses of blinding in the history of controlled experiment.

The commission's 1784 report concluded plainly that no physical magnetic fluid could be detected, and that the striking effects observed were produced entirely by the patient's imagination, a finding Bailly summarized by declaring magnetism "no more than an old falsehood." The verdict effectively ended animal magnetism's claim to scientific legitimacy, but not its practice: Mesmer's student the Marquis de Puysegur had already discovered magnetic sleep, an induced trance state, which developed independently into the tradition later renamed hypnotism by James Braid in the 1840s, while the broader idea of an invisible, channelable vital fluid went on to shape later concepts including od and, more loosely, twentieth century notions such as orgone.