In the same way as certain psychical phenomena, such as automatic writing, trance, "controls," crystal vision, and so forth, in which an intelligence seems to be present independent of the intelligence of the medium, can be shown beyond dispute to be merely manifestations of his subliminal intelligence, frequently taking the form of a dramatic personification; so may the agency, revealing itself in raps, movements of objects, and other phenomena of a physical character, perhaps be traceable, not to any power external to the medium and the sitters, but merely to a force latent within themselves, and may be an exteriorisation in a dynamic form, in a way not yet ascertained, of their collective subliminal capacities.
"Occultism and Common-Sense"
Beckles Willson