Like any
other discipline of science, parapsychology has a rich history. Numerous researchers
contributed to its development in one way or another, but many of them are
almost forgotten by now.
An influential person of the 19th century was industrial chemist Karl von Reichenbach (1788-1869) who is chiefly known for describing a universal and all-permeating force he called 'Od'.
Although he would have not considered himself a parapsychologist, von Reichenbach’s theory of Od had an important impact on theories concerning spiritualism, psychical research and concepts of vital forces.