Happiness and freedom begin with a clear understanding of one principle: some things are within our control and some things are not. It is only after you have faced up to this fundamental rule and learned to distinguish between what you can and can’t control that inner tranquility and other effectiveness become possible.
Within our control are our own opinions, aspirations, desires, and the things that repel us. These areas are quite rightly our concern, because they are directly subject to our influence. We always have a choice about the contents and character of our inner lives.
Outside our control, however, are such things as what kind of body we have, whether we’re born into wealth or strike it rich, how we are regarded by others, and our status in society. We must remember that those things are externals are therefore not our concern. Trying to control or to change what we can’t only results in torment.
Remember: The things within our power are naturally at our disposal, free from any restraint or hindrance; but those things outside our power are weak, dependent, or determined by whims and actions of others.
– Epicetus (50 AD – 135 AD), A Manual for Living