Manly Palmer Hall (March 18, 1901 - August 29, 1990) 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, which is widely regarded as his magnum opus, and which he published at the age of 27. He has been widely recognized as a leading scholar in the fields of religion, mythology, mysticism, and the occult.