Belief that the souls of the dead can make contact with the living, usually through a medium or during abnormal mental states such as trances. The basis of spiritualism is the conviction that spirit is the essence of life and that it lives on after the body dies. A medium is a person sensitive to vibrations from the spirit world, who may hold meetings known as séances in order to seek messages from spirits. A control is a spirit that gives messages to the human medium, who in turn gives them to other people. Spirits are also thought to manifest themselves through such means as rapping or levitating objects. Some spiritualists claim powers of paranormal healing. Scientific study of spiritualist phenomena has been the focus of the Society for Psychical Research, founded in Britain in 1882. See alsotheosophy.