“For a rational being, the only unbearable thing is unreasonableness, but anything reasonable is bearable. Being beaten isn’t in itself unbearable.
‘What do you mean?’
Look at it this way: the Spartans submit to being flogged once they’ve realized that it’s a reasonable thing to do.
‘But being hanged is unbearable, isn’t it?’
Except that when a person feels that it’s a reasonable thing to do, he’ll go and hang himself.
In short, if we look carefully, we’ll find that nothing distresses a rational being as much as what is unreasonable and, conversely, that nothing attracts it as much as what is reasonable.
But people’s views of what’s reasonable and unreasonable differ, just as their views of good and bad do, and what is or is not expedient.
This, above all, is why we need education, so that we learn how to adjust our preconceptions of what’s reasonable and unreasonable until they fit particular instances in a way that conforms with nature.” (Epictetus’s Discourses, book I, section 2)
Epictetus on what is or is not reasonable