Carlos S. Alvarado, PhD, Research Fellow, Parapsychology Foundation

“Over the years a number of ideas have been put forward based on the concept of radiations, or emanations, of biophysical forces from human beings. This concept, although generally disregarded by parapsychologists today, was once widely used to explain phenomena such as auras, ESP, healing, luminous effects, materializations, movement of objects, and many other events.” This is the beginning of an article I wrote about this topic that was published in the Psi Encyclopedia, an online project sponsored by the Society for Psychical Research (Human Radiations. In R. McLuhan (Ed.), Psi Encyclopedia. London: Society for Psychical Research, 2016).

Psi Encyclopedia

My emphasis in the article was on discussions about the topic published before the 1930s. This includes the literatures of mesmerism, Spiritism and Spiritualism, and psychical research.

I started with a section about mesmerism:

“In his book Mémoire sur la Découverte du Magnétisme Animal, the physician Franz Anton Mesmer . . . put forward several propositions about a universal fluid he called animal magnetism, which he believed could bring about actions in both organic and non-organic matter . . . This putative force was the central concept of mesmerism, a movement which flourished between the 18th and 19th centuries, and even later. It was said to be not only in the human body but all around in nature, and was thought to have healing properties. It was polarized like magnets, could be reflected by mirrors, and communicated to animate and inanimate matter, sometimes via sound.”


Franz Anton Mesmer

Mesmer Memoire 1779


In the words of one of Mesmer’s followers: “The magnetic fluid continuously escapes us: it forms an atmosphere around our body… which… does not act noticeably on individuals around us; but when our will pushes and directs it moves with all the strength that we impart: it moves like light rays sent out by bodies ablaze” (Deleuze, J.P.F. (1813). Histoire critique du magnétisme animal (Vol. 1). Paris: Mame.)


J.P.F. Deleuze

Deleuze Histoire Critique

There were many speculations about animal magnetism: “Some believed that animal magnetism was a nervous fluid intimately related to heat electricity and light . . . In fact, such ideas reinforced the notion of a universal force that could manifest in different forms. Petetin . . . called the force ‘animal electricity’ and stated that it could bring in information into the nervous system without the use of the eyes and other sensory organs.”

Petetin Electricite Animale 2 

Many books about mesmerism presented cures effected by this magnetic agent, a concept represented in the sketch below. “English physician James Esdaile . . . reported on amputations performed under the mesmeric state and listed many medical conditions successfully treated with magnetism in his medical practice in India.”


Esdaile Mesmerism in India

Another influential concept was an universal force proposed by Baron Karl von Reichenbach which he referred to as Od.

Reichenbach Physikalisch

“Od, Reichenbach thought, was produced by the human body, also by crystals, heat and other natural processes. He wrote: ‘I placed a specimen card of many metals before many high sensitives, who saw them all in the dark, some brighter, others darker. A glass case full of silver plate gradually grew to be full of fine fire. Coal, selenium, iodine and sulphur were all found to be luminous. The light was a phosphorescent glow, as though they were translucent . . . Besides the glow, the sensitives saw above these substances, flame-like emanations, losing themselves in smoke . . . , and in the former as well as in the latter cases, these flames could be made to nicker and be blown away by the breath, and they in many cases, throw light on the fingers, in which the objects were held. The colors of different substances varied greatly, and this variation gave a good test of the correctness of the statements of the sensitives.’ ”

Many ideas of forces were presented to explain the physical phenomena of mediums, “these were thought to emanate mainly from the body of the medium, although some theories also implicated the sitters in the séance, and more rarely, the surrounding environment.” Some of these ideas assumed spirit action while others did not.

One example of the later was Edward C. Rogers, whose book Philosophy of Mysterious Agents was widely cited during the 1850s and later. “Rogers postulated the exteriorization from the body of a nerve force which he believed accounted for physical phenomena in séances and for poltergeist disturbances. This could take place through unconscious guidance by a living agent or with no specific direction – basically an automatic process. He believed this force was the same as Reichenbach’s Od . . .”

Rogers Philosophy 1853

Variants of these ideas were published during the Nineteenth-Century by Edward W. Cox, Asa Mahan, Edouard von Hartmann, and many others.

Mahan Modern Mysteries

Cox Spiritualism Answered by Science

Von Hartmann Spiritism

English chemist and physicist William Crookes adopted Cox’s “psychic force” concept to make sense of the phenomena he observed with medium DD Home . . . He noticed that Home’s power to affect instruments was variable and speculated that they were related to the medium’s vitality. He wrote, ‘after witnessing the painful state of nervous and bodily prostration in which some of these experiments have left Mr. Home — after seeing him lying in an almost fainting condition on the floor, pale and speechless — I could scarcely doubt that the evolution of psychic force is accompanied by a corresponding drain on vital force.’ ” Crookes writings appear in his Researches in the Phenomena of Spiritualism, published in 1874.

Crookes Researches cover



D.D. Home

Other topics discussed include ideas of this sort to explain ESP, instrumental and photographic detectors of psychic forces. There is also a short section at the end of the article about critiques, and about recommended readings. I have discussed this topic before in several of my articles and blogs (click here, here, here and here.

Various Later Discussions of this Concept

Barety Magnetisme Animal

Baraduc Ame Humaine in Color

Joire Storage Annals of Psychical Science 1906