The Book on Mediums

The Book on Mediums or Mediums and Evokers' Handbook (a.k.a. The Mediums' Book —Le Livre des Médiums, in French), is a book by Allan Kardec published in 1861, second of the five Fundamental Works of Spiritism — the spiritualist philosophy Kardec had been publishing — being the tome in which the experimental and investigative features of the doctrine were presented, explained and taught.

It is intended to be an actual for would-be mediums, containing doctrine and practices that one must master in order to become a medium, an elementary course on theories and basic methods to assess the new light that had never been tried by rational inquiry before: the interaction of the physical and spiritual worlds.

The Book on Mediums set the bases and the terminology that guided Parapsychology and Paranormality for quite sometime. In its pages one will find a classification of paranormal phenomena, with a special focus on those capable of communicating messages, and thorough descriptions of the mechanisms that — according to Spiritism — were involved. It also contains serious warnings against unguided use of the gift of mediumship, especially without the necessary seriousness.

The book's signature is its focus on theory instead of practice: not a single line of ritual is given (Spiritists believe all rituals are superfluous), unless one consider recommendations for prayer (without giving formulae) as "ritual". In its first part, there is an overall introduction to the fundamental points of Spiritism. The following topics are examined within the book:

This part appears to contain a defense of Spiritism on empiric and logical grounds.

This last aspect shows that ever since the beginnings of Spiritism there were "deviant" groups with a different interpretation, some of which tried to identify themselves with the term Spiritism, which Kardec claimed to be an original term created by him to avoid such confusion.

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