Manly Palmer Hall was a Canadian-born author and mystic. He is perhaps most famous for his work "The Secret Teachings of All Ages: An Encyclopedic Outline of Masonic, Hermetic, Qabbalistic and Rosicrucian Symbolical Philosophy", published in 1928 when he was 27 years old. In 1934, Hall founded the Philosophical Research Society (P.R.S.) in Los Angeles, California, a profit orientated organization dedicated to the study of religion, mythology, metaphysics, and the occult. "P.R.S." maintains a research library of over 50,000 volumes, and also sells and publishes metaphysical and spiritual books, mostly those authored by Hall.