Spiritism is a spiritualistic doctrine codified in the 19th century by the French educator Hippolyte Léon Denizard Rivail, under the codename Allan Kardec, later called the Kardecist Spiritualism Doctrine, it proposed the study of "the nature, origin, and destiny of spirits, and their relation with the corporeal world". Spiritism soon spread to other countries, having today 35 countries represented in the International Spiritist Council.
Spiritism postulates that humans are essentially immortal spirits that temporarily inhabit physical bodies for several necessary incarnations to attain moral and intellectual improvement. It also asserts that spirits, through passive or active mediumship, may have beneficent or maleficent influence on the physical world.
The term first appeared in Kardec's book, The Spirits' Book, which sought to distinguish Spiritism from spiritualism.
Spiritism has influenced a social movement of healing centers, charity institutions and hospitals involving millions of people in dozens of countries, most of them in Brazil. Spiritism was also very influential in the new Vietnamese religion called Cao Đài or Caodaism, born in 1926 after three spirit mediums received messages that identified Allan Kardec as a prophet of a new universal religion. After 1975, Caodaism was almost closed down by the Vietnamese government, but it has now re-emerged on the public scene and Caodaists recently visited the Kardec Spiritist Center in Lyon to re-establish contacts with the legacy of French Spiritism. There are about four million Caodaists in Vietnam and in the Vietnamese diaspora, so they are the largest Spiritist group in Asia.