X. 35. A healthy eye is ready to see anything and doesn’t say, “I only want to see green things.” Such an eye would be diseased. And healthy hearing and smelling ought to be ready for anything. And a healthy stomach ought to be ready, just as a mill is ready for everything it has been designed to grind.
Just so, the healthy mind ought to be prepared for anything that happens. But a mind that says, “Let my dear children live,” or “may people praise everything I do” is like an eye that looks only for green things or teeth that seek only the soft.