The origins of hypnosis extend back to the ancient temples of Aesculapius, the Greek god of medicine, where advice and reassurance uttered by priests to sleeping patients was interpreted by the patients as the gods speaking to them in their dreams.
Roots in Mesmerism
The more recent history of hypnosis begins with Franz Anton Mesmer (1734-1815), who theorized that disease was caused by imbalances of a physical force, called animal magnetism, which affects various parts of the body. Mesmer also believed that cures could be achieved by redistributing this magnetic fluid -- a procedure that typically resulted in pseudoepileptic seizures known as "crises". In 1784, a French royal commission chaired by Benjamin Franklin and including Lavoisier and Guillotin among its members concluded that the effects of mesmerism, while genuine in many cases, were achieved by means of imagination and not by any physical force. In the course of their proceedings, the commissioners conducted what may well be the first controlled psychological experiments.
Mesmer's theory was discredited, but his practices lived on. A major transition occurred when one of Mesmer's followers, the Marquis de Puysegur, magnetised Victor Race, a young shepherd on his estate. Instead of undergoing a magnetic crisis, Victor fell into a somnambulistic (sleeplike) state in which he was responsive to instructions, and from which he awoke with an amnesia for what he had done. Later in the 19th century, John Elliotson and James Esdaile, among others, reported the successful use of mesmeric somnambulism as an anesthetic for surgery (although ether and chloroform soon proved to be more reliably effective).
James Braid, another British physician, speculated that somnambulism was caused by the paralysis of nerve centers induced by fixation of the eyes on an object. In order to eliminate the taint of mesmerism, Braid renamed the state "neurhypnotism" (nervous sleep); a term later shortened to hypnosis. Later, he concluded that hypnosis was due to the subject's concentration on a single thought (monoideism) rather than physiological fatigue.
Revival in Europe
Interest in hypnosis was revived in France in the late 1880s by Jean Martin Charcot, a neurologist, who thought that hypnosis and hysteria both reflected a disorder of the central nervous system. In opposition to Charcot's neurological theories, A.A. Liebeault and Hippolyte Bernheim, two other French physicians, emphasized the role of suggestibility in producing hypnotic effects. Pierre Janet and Sigmund Freud also studied with Charcot, and Freud began to develop his psycho-social theories of mental illness after observing the suggestibility of hysterical patients when they were hypnotized.
In the United States
William James and other early psychologists became interested in hypnosis because it seemed to involve changes in conscious awareness. The first systematic experimental work on hypnosis was reported by P.C. Young, in a doctoral dissertation completed at Harvard in 1923, and by Clark Hull in an extensive series of experiments initiated at the University of Wisconsin in the 1920s and continued at Yale into the 1930s. Also at Wisconsin during Hull's time was Milton Erickson, a physician whose provocative clinical and experimental studies stimulated interest in hypnosis among psychotherapists (Hull knew Erickson at Wisconsin, but the immediate source of Hull's interest in hypnosis was Joseph Jastrow, a prominent psychologist, who was Hull's mentor). After World War II, interest in hypnosis rose rapidly. Ernest Hilgard, together with Josephine Hilgard and Andre Weitzenhoffer, founded a laboratory for hypnosis research at Stanford University. Hilgard's status as one of the world's most distinguished psychologists helped establish hypnosis as a legitimate subject of scientific inquiry. Also important in this revival were Martin Orne, Theodore X. Barber, Theodore Sarbin, and Erika Fromm.