Readers, please enjoy this guest blog post by Loyd Auerbach, author of Psychic Dreaming and the new Mind Over Matter. Parapsychologists and psychical researchers have been studying psychokinesis (PK), or mind over matter, in the laboratory since at least the 1930s. However, PK has played a part in the field since scientists first began studying physical mediumship in the latter half of the 19th century. Physical mediums claimed to allow spirits to work through them to levitate objects, create apports and ectoplasm, and cause unusual sounds and other effects, all quite physical. For a variety of reasons, most researchers lean towards those effects being caused by the unconscious PK