The Spirits' Book
Book Two - The Spirit World
Chapter VI - Spirit Life
Relationships Beyond the Grave
282. How do spirits communicate with one another?
“They see and understand one another. Speech is a material creation that reflects the spirit. The universal fluid establishes constant communication, a vehicle by which thought is transmitted, similar to air being the vehicle of sound in your world. This fluid is similar to a universal telegraph, uniting all worlds and enabling spirits to correspond from one world to another.”