Modern period of western culture
Spiritualism is a monotheistic belief system or religion, postulating a belief in God, but with a distinguishing feature of belief that spirits of the dead residing in the spirit world can be contacted by “mediums”, who can then provide information about the afterlife.
Spiritualism developed in the United States and reached its peak growth in membership from the 1840s to the 1920s, especially in English-language countries. By 1897, it was said to have more than eight million followers in the United States and Europe, mostly drawn from the middle and upper classes, while the corresponding movement in continental Europe and Latin America is known as Spiritism.
The religion flourished for a half century without canonical texts or formal organization, attaining cohesion by periodicals, tours by trance lecturers, camp meetings, and the missionary activities of accomplished mediums. Many prominent Spiritualists were women. Most followers supported causes such as the abolition of slavery and women’s suffrage. By the late 1880s, credibility of the informal movement weakened, due to accusations of fraud among mediums, and formal Spiritualist organizations began to appear. Spiritualism is currently practiced primarily through various denominational Spiritualist Churches in the United States and United Kingdom.
Spiritism, or French spiritualism, is based on the five books of the Spiritist Codification written by French educator Hypolite Léon Denizard Rivail under the pseudonym Allan Kardec reporting séances in which he observed a series of phenomena that he attributed to incorporeal intelligence (spirits). His assumption of spirit communication was validated by many contemporaries, among them many scientists and philosophers who attended séances and studied the phenomena. His work was later extended by writers like Leon Denis, Arthur Conan Doyle, Camille Flammarion, Ernesto Bozzano, Chico Xavier, Divaldo Pereira Franco, Waldo Vieira, Johannes Greber, and others.
Spiritism has adherents in many countries throughout the world, including Spain, United States, Canada, Japan, Germany, France, England, Argentina, Portugal, and especially Brazil, which has the largest proportion and greatest number of followers.
The physician John Ferriar wrote “An Essay Towards a Theory of Apparitions” in 1813 in which he argued that sightings of ghosts were the result of optical illusions. Later the French physician Alexandre Jacques François Brière de Boismont published On Hallucinations: Or, the Rational History of Apparitions, Dreams, Ecstasy, Magnetism, and Somnambulism in 1845 in which he claimed sightings of ghosts were the result of hallucinations.
David Turner, a retired physical chemist, suggested that ball lightning could cause inanimate objects to move erratically.
Joe Nickell of the Committee for Skeptical Inquiry wrote that there was no credible scientific evidence that any location was inhabited by spirits of the dead. Limitations of human perception and ordinary physical explanations can account for ghost sightings; for example, air pressure changes in a home causing doors to slam, humidity changes causing boards to creak, condensation in electrical connections causing intermittent behavior, or lights from a passing car reflected through a window at night. Pareidolia, an innate tendency to recognize patterns in random perceptions, is what some skeptics believe causes people to believe that they have ‘seen ghosts’. Reports of ghosts “seen out of the corner of the eye” may be accounted for by the sensitivity of human peripheral vision. According to Nickell, peripheral vision can easily mislead, especially late at night when the brain is tired and more likely to misinterpret sights and sounds. Nickell further states, “science cannot substantiate the existence of a ‘life energy’ that could survive death without dissipating or function at all without a brain… why would… clothes survive?'” He asks, if ghosts glide, then why do people claim to hear them with “heavy footfalls”? Nickell says that ghosts act the same way as “dreams, memories, and imaginings, because they too are mental creations. They are evidence – not of another world, but of this real and natural one.”
Benjamin Radford from the Committee for Skeptical Inquiry and author of the 2017 book Investigating Ghosts: The Scientific Search for Spirits writes that “ghost hunting is the world’s most popular paranormal pursuit” yet, to date ghost hunters can’t agree on what a ghost is, or offer proof that they exist “it’s all speculation and guesswork”. He writes that it would be “useful and important to distinguish between types of spirits and apparitions. Until then it’s merely a parlor game distracting amateur ghost hunters from the task at hand.”
According to research in anomalistic psychology visions of ghosts may arise from hypnagogic hallucinations (“waking dreams” experienced in the transitional states to and from sleep). In a study of two experiments into alleged hauntings (Wiseman et al. 2003) came to the conclusion “that people consistently report unusual experiences in ‘haunted’ areas because of environmental factors, which may differ across locations.” Some of these factors included “the variance of local magnetic fields, size of location and lighting level stimuli of which witnesses may not be consciously aware”.
Some researchers, such as Michael Persinger of Laurentian University, Canada, have speculated that changes in geomagnetic fields (created, e.g., by tectonic stresses in the Earth’s crust or solar activity) could stimulate the brain’s temporal lobes and produce many of the experiences associated with hauntings. Sound is thought to be another cause of supposed sightings. Richard Lord and Richard Wiseman have concluded that infrasound can cause humans to experience bizarre feelings in a room, such as anxiety, extreme sorrow, a feeling of being watched, or even the chills. Carbon monoxide poisoning, which can cause changes in perception of the visual and auditory systems, was speculated upon as a possible explanation for haunted houses as early as 1921.
People who experience sleep paralysis often report seeing ghosts during their experiences. Neuroscientists Baland Jalal and V.S. Ramachandran have recently proposed neurological theories for why people hallucinate ghosts during sleep paralysis. Their theories emphasize the role of the parietal lobe and mirror neurons in triggering such ghostly hallucinations.