The idea of a mental reducing valve that constrains our perceptions, for instance, comes from the French philosopher Henri Bergson. Bergson believed that consciousness was not generated by human brains but rather exists in a field outside us, something like electromagnetic waves; our brains, which he likened to radio receivers, can tune in to different frequencies of consciousness. Huxley also believed that at the base of all the world’s religions there lies a common core of mystical experience he called “the Perennial Philosophy.”
