HYPNOTISM, or HYPNO'SIS (from Gk. Z7voc, hypnos,sleep). The general names for a group of abnormal phenomena, physical and psychical, which show a close outward resem blance to the phenomena of normal sleep and of sleep-walking. The symptoms of the hypnotic state differ considerably among different subjects, and the marking off of distinct stages within this state is rather a matter of theory than of actual observation. The artificial sleep is con tinuous and progressive, beginning with a lan guor and drowsiness not unlike those of a man suddenly waked from sound sleep, or arousing from a too protracted morning's nap after a disturbed night. As the state lvances, the sub ject becomes partially anc•sthei, insensitive to pin-pricks, pinching of the skin. his sense organs are closed to most of the impressions from his surroundings that would normally excite them; if awakened before the sleep has grown more profound. he remembers hazik what has occurred during hypnosis. He is extremely sug gestible at the hands of those who, as lie thinks, have induced the sleep. and will execute move ments that the experimenter prescribes to hon. The voluntary muscular system evinces a curious rigidity and fixity; the subject will remain in any position in which he is placed. This feature has given the name of 'catalepsy' (seizure) to the stage iu question. As the sleep is continued the subject becomes still more an:esthetic, until consciousness seems to lapse altogether; on waking, he has no memory whatsoever of the hypnotic period. The name of 'somnambulism' is given to a stage of profound hypnosis in which illusions are produced at the experimenter's sug gestion: the subject takes ink for wine, a pillow for a baby, steps carefully over an imaginary book. etc., etc.
These phenomena of sleep Or trance, mixed with much that is simply charlatanry, have been discussed and exploited from time immemorial. The medicine-men of primitive and savage tribes, the magicians of Egypt and the Hindu ascetics, the monks of :Mount Athos, the quack physicians of all ages, have made use of hypno tism to enhance their personal prestige, to cure the sick, or to induce states of religious ecstasy.
The modern history of hypnotism begins with F. A. Alesmer (1733-1815), a German physician who practiced hypnotic therapeutics at l'aris from 1778, causing so great a stir in scientific circles that his pretensions were made a matter of inquiry by a royal commission (1785). The report of the commission was unfavorable; but 'mesmerism' still flourished. In England valu able works wepe published in the early forties by J. Braid, a Nanchester surgeon (C.1795-1860) ; hut their sanity and importance have but recently been fully recognized. Braid coined the word 'neurohypnotism,' or nerve sleep, from which comes the modern word hypnotism. During the last third of the nineteenth century the facts of hypnosis were thoroughly investigated by physiologists and psychologists. licidenhain and Preyer in Germany, ]ticket, Charcot, LiM)ault, and Bernheim in France, Dellneuf in Belgium, confirmed and extended Braid's results. The French investigators split into two distinct `schools': that of Chareot and his followers at the Paris Hospital of the SalOtriere, and that of Bernheim and his followers at Nancy. The Sal p•riere school maintains that hypnotism is a pathological phenomenon. akin to hysteria, and characterized by three well-marked stages: the school of Nancy asserts that it can be set up in the normal individual, that it is a unitary and progressive stage, and that the key to its under standing is given with the facts of suggestion. The latter views have found general acceptance: but the controversy undoubtedly hindered the advance of knowledge and threw discredit upon the whole subject. It need hardly be said that the doctrines known as animal magnetism. elee tro-biology, odism or odylism, mesmeric clair voyance. etc., are one and all—save in so far as they cover the facts of hypnotism proper—fanci ful and ungrounded hypotheses.