Moving from principle to practice, Stoicism often summarizes its ethics with the dichotomy of control. Epictetus’ *Enchiridion* (c. 125 AD) opens by separating “things up to us” from “things not up to us,” and the quote you provided captures the emotional cost of confusing the two.
Consider a common scenario: you may control whether you prepare thoroughly for an interview, but not whether the interviewer is biased, distracted, or constrained by budgets. If you value the offer itself above all else, you become vulnerable to every contingency; if you value your preparation and character, you retain composure regardless of the final decision. [...]