[uh-quan]

That isn't quite what Epictetus means by what's under our control.

Back then one could generally travel from one end of the Roman Empire to the other (e.g., from England to Persia) safely, on well-built and -guarded roads, needing knowledge of but one language and possession of but one currency — all this despite traveling through a dozen+ diverse cultures and nations on the trip. A few centuries later, and for more than a millennia afterward, that would be impossible. But Epictetus would still categorize the success of such a journey as something out of our control: What if a robber attacks you, in spite of the general safety of the roads? What if you fall off your horse and snap a leg? What if you get sick? What if a storm unexpectedly hits during a sea voyage?

Similarly, on a trip to the moon: What if the rocket fails to launch? What if it launches but explodes in the atmosphere? What if your second-stage engine fails to fire? What if, en route to the moon, an electrical malfunction depletes your oxygen reserves to dangerously low levels? Etc. I pick these examples because they've all actually happened, despite our best efforts to the contrary.

The moral question Epictetus considers is not, What is it Man (in the abstract) is capable (sometimes) of doing? The question is, what is truly under your control? What is the interior castle into which no one and no thing can invade if you do not permit it to enter? What are the implications of having such an interior fortress, and how might we leverage that control to live happy lives?

The answers to those questions have not changed in the thousands of years since Epictetus asked them. Stoicism is a perennial philosophy.