The Manual for Living
by Epictetus
From The Book:
What disturbs men's minds is not events but their judgments on events.
If you wish to make progress, you must be content in external matters to seem a fool and a simpleton; do not wish men to think you know anything, and if any should think you to be somebody, distrust yourself.
Know then that when your own cup is broken, you ought to behave in the same way as when your neighbor's was broken.