The Enchiridion, or "Handbook," is a summary of the teachings of the slave-turned-Stoic philosopher Epictetus (first century A.D.) posthumously compiled and published by one of Epictetus' students. Though brief, this work is universally considered to be the living spirit of Stoicism, wherein the principles of right conduct and true thinking are outlined.<br><br>The Enchiridion has played a significant role in the development of modern philosophy and intellectual attitudes, showing secular thinkers how sound reasoning can free them from the shackles of absolutism and emotionalism and, in so doing, live a more tranquil and productive life.