A peculiar altered state of consciousness distinguished by certain marked symptoms, the most prominent and invariable of which are the presence of continuous alpha waves on the electroencephalograph, hyper suggestibility in the subject, a concentration of attention on a single stimulus, and a feeling of “at oneness” with the stimulus. Hypnotic states may be induced by various techniques applied to oneself or by another.
The hypnotic state may be induced in a large percentage of normal individuals, or may occur spontaneously. It is recognized as having an affinity with normal sleep, and likewise with a variety of trance-like conditions, among which may be mentioned somnambulism, ecstasy, and the trances of Hindu yogis and fakirs, and various tribal shamans. In fact, in one form or another, hypnosis has been known in practically all countries and periods of history.
Hypnotism, once classed as an occult science, has gained, though only within recent years, a definite scientific status, and no mean place in legitimate medicine. Nevertheless, its history is inextricably interwoven with occult practice, and even today much hypnotic phenomena is associated with the psychic and occult, so that a consideration of hypnotism remains a necessary component in any mature understanding of the occult world science of both our own time and the past.