In this classic of stoic philosophy, Epictetus gives short rules for living a well-ordered life, defined by knowing what is in your control and not getting upset about what isn't. Compiled by his student Arrian from classroom lectures, it distills a lifetime of ethical teaching into fifty-two short precepts. In true Stoci fashion, there's no metaphysics, cosmology, or fluff, just clear nd simple rules for living a considered and well-balanced life.

The basic principle is is simple: separate what depends on you from what doesn't. Epictetus says you should focus on the things that are on your side, like judgment, impulse, desire, and aversion, and ignore or rise above the things that are not on your side, like body, property, reputation, office, and death itself. Everything outside your will is “indifferent”—not because it lacks value, but because it's not in your control. If it's not down to you, why worry about it? He says we should treat any disturbance we can't control as a mistake in our own reasoning, then to correct that mistake on the spot.

The Enchiridion proposes that when someone insults you, you should remember that they judge appearances, not truth. When a loved one travels or dies, remind yourself that departure is part of nature. When desire pulls you toward a goal, pause and examine the cost of being disappointed. When you lose something, say simply that it's been 'returned', not lost.

This Stoic handbook has influenced major figures for millennia. After influencing Marcus Aurelius' Meditations, it was referenced by Michel de Montaigne and Blaise Pascal, carried on his military campaigns by Frederick the Great, and went on to profoundly influence the works of Matthew Arnold and Ralph Waldo Emerson. Even now influences the approach of Cognitive Behavioural Therapy.