In Lectures on Ancient Philosophy, Manly P. Hall expands on the philosophical, metaphysical, and cosmological themes introduced in his classic work, The Secret Teachings of All Ages. Hall wrote this volume as a reader's companion to his earlier work, intending it for those wishing to delve more deeply into the esoteric philosophies and ideas that undergird the Secret Teachings. Particular attention is paid to Neoplatonism, ancient Christianity, Rosicrucian and Freemasonic traditions, ancient mysteries, pagan rites and symbols, and Pythagorean mathematics.