Epictetus wrote enchoridian centuries ago.
The paragraph where he mentions what things we have in our control and we don’t have has been a principle for me. I consider lucky getting to know about it, soaking it up.
Many things we do in our lives with our best efforts. But if we decide the result or expect the outcome in our favor and it goes opposite we get miserable. At times anger takes over.
Going by Epictetus, I know it is a difficult life to lead. Leaving outcome aside and focusing on putting the best effort. Life is more content. We do not regret not trying.
Life with action as prime motivation does more wonders that has a goal.