“...The danger in dealing with these spirits lies in their tendency to mirror the magician's own subconscious darkness; one may think he is receiving divine secrets from a demon, when he is merely being led further into the labyrinth of his own delusions.” ― Dion Fortune, Psychic Self-Defense, 1930 (Rider & Co.), p. 164.
“Communication with interdimensional entities is a double-edged sword; while they offer insights beyond human reach, the price is often the practitioner's mental stability, as these beings operate on a frequency that can shatter the unprepared ego.” ― Israel Regardie, The Tree of Life: A Study in Magic, 1932 (Rider & Co.), p. 203.