The Secret Doctrine has been acknowledged by many as one of the most remarkable books in the world. It is considered to be the Bible of Theosophy, a sourcebook of the esoteric tradition that outlines the fundamental tenets of the secret doctrine of the past ages. “The Secret Doctrine” explains the origin and evolution of the universe and of humanity through an account of “Root Races” dating back millions of years. The writer Madame Blavatsky often expressed that she was only the compiler of ancient wisdom that was passed on to her. The true authors of the work were her teachers, the Mahatmas, or Great Souls, who were the guardians of the Secret Wisdom of the ages.