Your judgments, aims and choices are up to you; your body, property, reputation and how events turn out are not, so put your effort and your worry where your power is.
You have met this advice before, probably in a recent book: work on what you can control and let the rest go. The idea is at least 1,900 years old. The earliest place we can find it is a short handbook of Epictetus’s teaching, written up by Arrian around 125 CE. The same line has kept coming back since, through Montaigne in 1580, Descartes, Bertrand Russell, the Serenity Prayer and Covey’s Circle of Influence in 1989, and most of them don’t say where it came from. One book on this page argues against it.
Older hints exist: Epicurus and Aristotle on what is in our power, the Gita on the deed and its fruit, Chrysippus on fate as Cicero reports him, but none gives this advice in this form. Enchiridion 1 is the earliest place we can find that does.
“There are things which are within our power, and there are things which are beyond our power. Within our power are opinion, aim, desire, aversion, and, in one word, whatever affairs are our own. Beyond our power are body, property, reputation, office, and, in one word, whatever are not properly our own affairs.”
Full text read.
Epictetus, Enchiridion 1, tr. Thomas Wentworth Higginson (1865).
What pains you is your own judgment about the thing, Marcus writes, and that judgment is in your power to wipe out. Near the end of the book he credits the rule to Epictetus: show no aversion to what is not in our power (11.37).
“If thou art pained by any external thing, it is not this thing that disturbs thee, but thy own judgment about it. And it is in thy power to wipe out this judgment now.”
Full text read.
Marcus Aurelius, Meditations, tr. George Long (1862).
Descartes’s third maxim states the split and the advice in his own words, conquer yourself rather than fortune, and mentions earlier philosophers without naming one.
“My third maxim was to endeavor always to conquer myself rather than fortune, and change my desires rather than the order of the world, and in general, accustom myself to the persuasion that, except our own thoughts, there is nothing absolutely in our power”
Full text read.
René Descartes, Discourse on Method, Part III, tr. John Veitch.
Bennett says your own mind is what you can control, has the reader object that this is old, and agrees: Epictetus, Marcus Aurelius and Christ said it.
“But your own mind you can control. [...] ‘Oh, yes!’ you protest. ‘All that’s old. Epictetus said that. Marcus Aurelius said that. Christ said that.’ They did.”
Wattles puts property and outcomes inside your power: with the right thinking you can have the things you want. He never raises the question of control.
“You can certainly have a sewing machine in your house; and it is just as certain that you can have any other thing or things which you want, and which you will use for the advancement of your own life and the lives of others.”
Russell’s wise man acts on preventable misfortunes and spends no time or emotion on unavoidable ones, the same advice in his own words, and he names no one.
“The wise man, though he will not sit down under preventable misfortunes, will not waste time and emotion upon such as are unavoidable”
The 1933 printing, as Wikipedia quotes it, states the split and the advice in its own words and credits no one; the Epictetus comparison is Wikipedia’s own.
Wikipedia’s account of the book: Oh, God, give us courage to change what must be altered, serenity to accept what can not be helped, and insight to know the one from the other.
Secondhand, from Wikipedia. Reinhold Niebuhr, as printed by Winnifred Wygal, The Serenity Prayer (1933).
We read this 1933 printing as Wikipedia quotes it, not the printing itself.
Wikipedia has Covey telling you to focus on your Circle of Influence rather than your Circle of Concern, crediting no one; Frankl is named for a nearby point.
Wikipedia’s account of the book: He goes on to introduce the concepts of the Circle of Influence and the Circle of Concern, advising individuals to focus their responses on the center of their own influence.
Secondhand, from Wikipedia. Stephen R. Covey, The 7 Habits of Highly Effective People (1989).
This book is still in copyright, so we read an account of it, not the book.
Daily Stoic’s summary gives the book’s first lesson as the split (opinion, desire and impulse are ours) plus the advice to put effort there, credited to Epictetus.
“Opinion, desire, impulse: all of these are within our control, Epictetus said.”
Secondhand, from Daily Stoic. Massimo Pigliucci, How to Be a Stoic (2017).
This book is still in copyright, so we read an account of it, not the book.
Our free sources disagree on whether the book credits Epictetus. Two summaries name no one; a third (Via Stoica) quotes Irvine’s trichotomy and says he restates Epictetus. Three blind readers split on it (Cites, Conflicts, Cites, all low confidence). We hold it back until the book’s own words on Epictetus turn up on a cleared source.
How this page was made. AI agents did the reading. Each link was judged by two readers from different AI models, working blind; a third settled their splits (7 of 9 links on this page needed no tiebreak). Every quote was checked word for word against its source. “Full text read” means the agents read the book itself; “Author’s own words” means the author’s free writing elsewhere; “Secondhand” means a free summary or article about the book.