Summary of "On Tranquility of Mind"

Core Idea

Tranquillity comes from how you think, not what happens — wealth, status, and hardship are neutral; your reasoning shapes your peace
You control only your character and choices — everything else (health, reputation, outcomes) is outside your power; stop fighting this reality
Train your mind before crisis arrives — rehearse loss and disappointment so they don't devastate you when they come

Look at what you have, not what others possess — when envying someone, also see their servants, sufferings, and hidden pain
Reset your benchmark downward — regularly name three people worse off than you; this rewires what feels like scarcity

Your mind gravitates to pain like a magnet — consciously redirect focus to good things present and past
Actively recall past blessings — don't let memory steal them; rehearse fair voyages, good health, peaceful days regularly
Accept life's mixed nature — harmony needs low and high notes; stop demanding purity or constant happiness

Loss often contains hidden gain — exile taught Diogenes philosophy; shipwreck freed Zeno from commerce
Other people's failures aren't your moral failure — your wife's infidelity, your child's mistake — these are their slips, not reflections of you
Separation from power is freedom — losing an election means leisure and country living; rejection from office means safety

Stop expecting mastery in all domains — you cannot be rich, learned, powerful, eloquent, and humble simultaneously
Stop resenting what others have instead of using what's yours — read one poem carefully rather than resenting you don't own a library
Stop waiting for special days to be happy — treat every day as a festival; life itself is the sacred ritual
Stop absorbing others' anger and vice — treat it like barking dogs; don't let their sickness infect you

Your opinions, knowledge, virtue, and character are indestructible — Fortune controls your body and possessions, never your soul
Right actions leave lasting joy in memory — good deeds sweeten old age better than hope; regret wounds forever
A clear conscience is the only tranquillity that costs nothing — more valuable than any house or office

This week: list three fears (loss of money, status, health). Sit with each for 10 minutes; write what you'd actually do. Realize you'd survive.
Daily: pause when comparing yourself to others. Name three people worse off; reset your benchmark downward.
Weekly: write one good thing you overlooked. Train active gratitude; stop letting life steal itself through inattention.
Before bed: review only your choices. Did you lie, cheat, scheme? If yes, sit with the sting and resolve differently. Regret here is useful; regret about externals is waste.
When upset: ask "Is this in my control?" If no, release it immediately. If yes, use reason to respond; never react.