No man is free who is not master of himself.Epictetus
“Freedom is the only worthy goal in life. It is won by disregarding things that lie beyond our control.”
Stoic philosopher · 50 – 135
Epictetus was a Greek-born slave in Rome who won his freedom and became one of the most influential Stoic teachers. His Discourses and the handbook known as the Enchiridion teach that freedom lies in mastering one's own judgments and desires.
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We have two ears and one mouth so that we can listen twice as much as we speak.Epictetus

Don't demand that things happen as you wish, but wish that they happen as they do happen, and you will go on well.Epictetus
Keep silence for the most part, and speak only when you must, and then briefly.Epictetus
One that desires to excel should endeavour in those things that are in themselves most excellent.Epictetus

Some things are within our power, and some things are not.Epictetus
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It's not what happens to you, but how you react to it that matters.Epictetus