Some things are within our power and some are not, and nearly every human misery begins with the confusion of the two. Epictetus, born a slave in Hierapolis around 50 AD, never wrote a word; this slim handbook was assembled by his student Arrian from the lectures of a man who had learned philosophy not in a library but in bondage. The Enchiridion strips Stoic thought to its barest instructions: distinguish what you can control from what you cannot, and desire only the former. Its brevity is not simplicity but compression, each maxim forged under the pressure of lived suffering. Sixteen centuries later it traveled in the packs of soldiers and the pockets of statesmen, proving that the truest wisdom fits in the palm of one hand.