Mesmerism, also called Animal Magnetism, was coined by the German doctor Franz Mesmer (1734 – 1815). He claimed that there’s an invisible natural Life Force or Vital Energy — called Lebensmagnetismus — possessed by all living things, which includes human beings, animals, and vegetables.
Mesmer believed that this Lebensmagnetismus could be used, and was a kind of “magnetic fluid” or “fluid matter” that could have physical healing effects, for instance, by treating patients (humans and animals) with Laying on of Hands i.e. Hand Palm Healing techniques.
The idea of this “magnetic fluid” is that it’s a universal principle of “fluid matter” that occupies all space, which can flow from one body to another, as in a magnet. A body that has more “magnetism” than another body, more motion, communicates it to the other body, until there’s a balance i.e. equilibrium between the two bodies. This is what Mesmer called Animal Electricity or Animal Magnetism.
The practitioners (therapists) of Mesmerism are usually known as magnetizers. It was an important specialty in medicine in the 18th and 19th century, and it’s still practiced as a form of complementary or alternative medicine in some countries.
Nevertheless, today, the word Mesmerism itself generally functions as a synonym of hypnosis. The reason of this is the effects and feelings of a patient of a “mesmerizing treatment,” which typically includes intense heat, trembling, vomiting, trances, and/or seizures.
Some claim that the effects of Mesmer therapy are not induced by the magnetizer, but come from the patient, and takes place in the patient’s imagination, that is, apparent healing is rendered through a form of autosuggestion generated from within the mind.