Mesmerism / Animal Magnetism

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Mesmerism, or animal magnetism, is the healing theory and practice developed by the Viennese physician Franz Anton Mesmer (1734–1815), built on the claim that a subtle, invisible fluid fills the universe and flows through every living body, and that disease is a disturbance in its movement which the right kind of treatment can set right. The name animal magnetism marked the fluid as a force proper to living things, distinct from the mineral magnetism of the lodestone, though Mesmer first arrived at it by way of magnets and only later set them aside.

The fluid and its cosmos

The doctrine is a fluidic monism. In the Mémoire sur la découverte du magnétisme animal (Geneva and Paris, 1779), Mesmer condensed his teaching into a closing set of twenty-seven propositions, the first of which posits a single, universally diffused, imponderable medium: a fluid continuous enough to admit no vacuum, the vehicle of a mutual influence among the celestial bodies, the earth, and animate beings, and — like the sea — subject to flux and reflux. Health is the free and harmonious circulation of this fluid through the body; disease is an obstacle to its flow; cure consists in restoring the flow, often by provoking a salutary crisis. The fluid can be stored, reflected by mirrors, and conducted — by sound, by iron, and above all by the operator’s hand or fixed gaze. Animal magnetism names not the fluid as such but the property of living bodies that makes them susceptible to this cosmic tide.

The roots of the conception reach back into a long tradition of sympathetic medicine and graded cosmologies. Mesmer’s 1766 Vienna dissertation, De planetarum influxu, had argued, on the model of Newton’s account of the tides, that sun and moon raise tides in the human body through an invisible medium — an animal gravitation he would later rename. The work leaned heavily, to the point of verbatim borrowing, on Richard Mead’s De imperio solis ac lunae (1704), a debt established by the historian Frank A. Pattie, though originality was not then a doctoral expectation and the borrowing reads against period norms rather than as misconduct. Behind the dissertation stands the older lineage that runs through Paracelsus and his sidereal anthropology, through the Helmontian doctrine of a vital archeus diffused through the cosmos, and through the seventeenth-century talk of sympathy and magnetism that was already standard medical idiom when Mesmer reached for it. His decisive move was to fix the agent: not the magnet, not the star, but a vital fluid the trained operator could direct.

The separation of animal from mineral magnetism was hard-won. Mesmer began about 1773–75 using magnetized steel plates obtained through the Jesuit court astronomer Maximilian Hell, and only after a priority quarrel with Hell did he insist that the curative agent was never the steel but the fluid he could channel without it. The point was doctrinally sharpened in 1775 at Munich, where Mesmer was invited before a commission to assess the celebrated exorcistic cures of the priest Johann Joseph Gassner. Mesmer reproduced and dispelled the same symptoms without exorcism and declared that Gassner had been healing by animal magnetism all along without knowing it — a clean translation of a charismatic, religious healing relation into a naturalistic one, and a template for how the new doctrine would absorb older practices by reading them as instances of its single force.

Vienna to Paris: the baquet and the crisis

Mesmer brought the practice from Vienna to Paris in February 1778, after the Viennese scandal surrounding his treatment of the blind pianist Maria Theresia von Paradis, and there it became a sensation. He treated individually — sitting knee-to-knee with the patient, pressing the thumbs, holding the gaze, drawing his hands in long passes along the body to direct the fluid. To meet the crush of demand he treated in groups around the baquet: a covered wooden tub filled with magnetized water, iron filings, and bottles, from which protruding iron rods could be pressed to the afflicted parts, while patients linked hands or were joined by cords into a conducting chain and music — often the eerie tones of the glass armonica — played through the room. Treatments often built to a convulsive crisis, taken as the sign of the cure working; the more violent seizures were managed in a padded crisis room set aside for them. The Paris clientele was broad but skewed fashionable and disproportionately female, and the spectacle fused therapeutics, salon sociability, and theater. The success of the cures, and the fees, drew both crowds and suspicion.

The movement took an institutional form that later esoteric orders would inherit nearly intact. The Société de l’Harmonie Universelle, founded in 1783 and formalized in 1784, sold Mesmer’s secret to fee-paying subscribers — a hundred louis a head — and initiated them through a graded, quasi-Masonic structure, with provincial affiliates at Lyon, Bordeaux, and Strasbourg. By the reckoning of the historian Robert Darnton, within two years the society had earned nearly 350,000 livres and spawned three provincial societies. Its first prominent convert, the physician Charles Deslon, helped launch the doctrine and then diverged into an independent practice — and it was Deslon’s practice, not Mesmer’s, that the crown would eventually put on trial. Internal politics, as the financier Nicolas Bergasse and his circle tried to bend mesmerism toward political reform, fractured the society; Mesmer expelled Bergasse and his ally Kornmann in 1785.

The 1784 royal commission

In March 1784 Louis XVI appointed not one investigative body but two. The first, drawn from the Académie des sciences and the Faculté de médecine, is remembered for its membership: Benjamin Franklin, in whose garden at Passy much of the testing was done; the chemist Antoine Lavoisier, who designed the crucial comparisons; the astronomer Jean-Sylvain Bailly, who drafted the report; and the physician Joseph-Ignace Guillotin, among others. Because Mesmer refused to cooperate, the commissioners examined Deslon’s practice — and, noticing that they themselves felt nothing in the group sessions, set out to separate the postulated physical agent from the patient’s expectation.

The method was a milestone in the design of the controlled experiment. The commissioners blindfolded subjects and told them, truly or falsely, that they were being magnetized; reactions tracked the belief rather than the procedure. In the celebrated test in Franklin’s garden, a susceptible patient was led to several trees, one of which Deslon had magnetized, and fell into crisis at the wrong tree — an unmagnetized one — while believing the fluid was present. Subjects drank sham-magnetized water and convulsed; they drank genuinely magnetized water, unaware, and felt nothing. The verdict, signed on 11 August 1784, was that no fluid could be detected, and that the effects the practice produced were the work of imagination, imitation, and touch. A second commission, of the Société Royale de Médecine, concurred — though Antoine Laurent de Jussieu broke from it in a dissenting minority report, allowing that some physiological agent, perhaps animal heat, might yet be at work. A further, secret report to the King warned that the intimacy of the crisis, between a male magnetizer and largely female patients, made the practice a danger to morality, and urged the crown to curb it.

The inquiry is widely counted among the first coordinated uses of blinded, placebo-controlled testing and the first to isolate suggestion and expectation as a causal variable — a foundational episode in the histories of the controlled trial, the placebo concept, and evidence-based medicine. Its finding damaged mesmerism’s standing as official medicine without ending its life as practice. And the precise shape of the verdict mattered for everything that followed: the commissioners did not so much disprove Mesmer’s deeper claim — that imagination acts physically on the body — as reclassify it, moving the active principle from a cosmic fluid to the mind of the patient. That reclassification is the hinge on which the next century turned.

Puységur’s turn: from crisis to somnambulism

What survived the commission took a direction its founder had not intended. Late in the same year, 1784, the Marquis de Puységur — an artillery officer and member of the Harmonie — magnetized a young man in his employ, the peasant Victor Race, on his estate at Buzancy. Instead of a convulsion, Victor sank into a calm, sleep-like, lucid state: he spoke articulately and out of his waking character, appeared to diagnose illness, followed instruction, and on waking remembered nothing. Puységur called it the perfect or tranquil crisis, then magnetic sleep, then artificial somnambulism.

This is the hinge of the whole history. The phenomena Puységur cataloged in his 1784 Mémoires — the trance itself, the rapport between operator and subject, the apparent clairvoyance, the spontaneous amnesia on waking, the suggestible second condition with its own chain of memory — became the canonical phenomena of what a later century would rename. Where Mesmer stayed committed to the physical fluid and the convulsive crisis, the living future of the movement ran through Puységur’s quiet, divided state of mind. The center of gravity shifted from fluid mechanics to altered selfhood, and it is along that shifted axis that mesmerism fed forward into hypnosis and the study of suggestion.

Two afterlives

From this point the reception splits, and the split is the heart of the story. Both lines descend from the same eighteenth-century practice; they differ in what they take its central fact to be.

Along the first, scientific channel, the somnambulic trance was gradually stripped of the fluid. In Britain John Elliotson championed mesmeric therapeutics and founded the journal The Zoist; James Esdaile performed surgery on entranced patients in Bengal in the 1840s. The decisive conceptual break came with the Manchester surgeon James Braid, whose Neurypnology (1843) recast the phenomena as a psycho-physiological nervous sleep induced by fixed attention rather than by any transmitted fluid, and coined the term that would replace magnetism. From Braid the line runs to the Nancy school of Liébeault and Bernheim, who reduced the trance to ordinary suggestion and suggestibility, and to the rival Salpêtrière school of Charcot, who tied it to hysteria; the suggestion model carried forward into Janet’s work on dissociation and into the early thought of Freud, who visited Bernheim in 1889. Through this channel mesmerism became the matrix of modern hypnosis, the clinical study of suggestion, and the dawning idea of an unconscious mind.

Along the second, esoteric channel, the fluid and the lucid somnambule were kept and elaborated. Puységur’s entranced subjects were quickly credited with traveling clairvoyance and spirit diagnosis; the industrial chemist Karl von Reichenbach renamed the subtle agent the od (odic force), perceptible only to sensitives; in Germany Justinus Kerner’s case of the entranced seeress Friederike Hauffe joined magnetic somnambulism to a full visionary anatomy. In the United States the self-taught clairvoyant Andrew Jackson Davis, dictating in magnetic trance, constructed a layered cosmology of ascending spheres that drew openly on Emanuel Swedenborg — and the seven-sphere afterlife of his Great Harmonia (1850s) was already in print years before the Hydesville rappings of 1848 launched modern spiritualism. The mesmeric trance, the clairvoyant somnambule, and magnetic healing furnished the working templates — trance mediumship, spirit diagnosis, the laying-on of hands — on which spiritualist practice was built, and fed onward into the mental-healing currents of New Thought.

The same fluid, recovered under new names, became load-bearing for nineteenth-century occultism. Eliphas Lévi fused the magnetic-Reichenbachian medium with Renaissance magical and Kabbalistic vocabulary and called it the astral light — Mesmer’s fluid plus the Paracelsian imagination plus the anima mundi — and it was Lévi’s term, taken up by Helena Blavatsky, that organized the sevenfold human constitution of Theosophy. Scholars of Western esotericism such as Wouter Hanegraaff and Karl Baier have argued that the conceptual lattice into which Theosophy later poured its Sanskrit terms — prāṇa, liṅga-śarīra, kāma-rūpa — was already Mesmerist, Reichenbachian, and spiritualist; the astral body of late-nineteenth-century occultism is, on this reading, a magnetic-fluid descendant clothed in Eastern vocabulary, a thread the broader Hermetic revival carried into the twentieth century. The idea of a vital force passing between bodies, of rapport and influence at a distance, also stands behind the later language of telepathy as it was formalized by the psychical researchers who inherited the somnambulic-clairvoyant thread.

Scholarship and the primary record

Three lines of modern scholarship carry the subject. The social and political history was set by Robert Darnton’s Mesmerism and the End of the Enlightenment in France (1968), which reads Parisian animal magnetism as a vehicle of radical, anti-establishment popular science in the decade before the Revolution. The history-of-psychotherapy line — the through-line from Puységur to hypnosis and dynamic psychiatry — is anchored by Adam Crabtree’s From Mesmer to Freud (1993), Alan Gauld’s A History of Hypnotism (1992), and Henri Ellenberger’s The Discovery of the Unconscious (1970), which treat magnetic sleep as the matrix of the modern unconscious. The biographical and doctrinal record was put on a documentary footing by Frank A. Pattie, whose 1994 study established both the Mead borrowing and the textual shape of the doctrine. For the forward genealogy into spiritualism and Theosophy, Joscelyn Godwin’s The Theosophical Enlightenment (1994) and the work of Hanegraaff and Baier are standard.

The primary corpus is almost wholly in the public domain and digitized. Mesmer’s foundational Mémoire sur la découverte du magnétisme animal (1779), with its twenty-seven propositions, is the doctrine in the author’s own words. Puységur’s Mémoires (1784) documents the somnambulic turn case by case. The commissioners’ Rapport des commissaires chargés par le Roi, de l’examen du magnétisme animal (1784) is the verdict in full, printed by order of the King and circulated across Europe within weeks; the episode is treated as a landmark of trial design in the James Lind Library and as the prototype of the modern clinical trial in the Public Domain Review. James Braid’s Neurypnology (1843), which severed the practice from the fluid and gave hypnotism its name, marks the far end of the scientific channel. (George Bloch’s 1980 English translation of Mesmer remains in copyright and circulates only in print.)

The mesmerist at the crossroads

The figure of the mesmerist sits where these channels divide. Read from the side of the laboratory, Mesmer’s fluid was an error that nonetheless opened a real subject — the power of expectation over the body — and the 1784 commission a triumph of method. Read from the side of the esoteric currents that took him up, the fluid was no error but a glimpse of a genuine vital medium, and the trance a doorway. Neither reading exhausts the eighteenth-century thing itself, which was narrower and stranger than both: a particular healing practice, performed around a tub to the sound of a glass armonica, that provoked one of the first controlled investigations of a medical claim — and whose afterlife ran in two directions at once, into clinical hypnosis on one side and into the occult on the other.

→ Related: Theosophy · Modern Hermeticism Hermetic Revival · Franz Anton Mesmer · Hypnosis · Spiritualism · Occultism · Paracelsus · Eliphas Levi Alphonse Louis Constant · Helena Blavatsky · Telepathy · New Thought American Metaphysical Religion · Emmanuel Swedenborg · Swedenborgianism