He published numerous books and articles on topics such as telepathy, spiritualism, telekinesis, etc.
He was inspired by the British Society for Psychical Research, and with philosopher Traugott Konstantin Oesterreich (1880-1949) tried to establish a similar institute in Germany.
[1] Among his most important contributions to the field of parapsychology were his experiments in clairvoyance, conducted at a time when most such research concerned telepathy.
Tischner's monograph Telepathie und Hellsehen (1921) collected his reports on these studies.
[2] In this work, Tischner referred to telepathy and clairvoyance as instances of a more general faculty of Außersinnlicher Wahrnehmung, thus, in its translation, coining the term extrasensory perception.