You ought to possess your whole body as a poor mule loaded, as long as it is possible, as long as you are allowed. But if there be a press, and a soldier should lay hold of it, let it go, do not resist, nor murmur; if you do, you will receive blows, and nevertheless you will also lose the mule.
Epictetus, Discourses. Book IV
Interestingly, the second part of this quote is a lot more practical, when not fraught with the burden of a philosophical analogy.