From the Meditations — Marcus Aurelius

When you wake, tell yourself: today I will meet people who are meddling, ungrateful, arrogant, dishonest, envious, and unsociable. All this has come upon them through ignorance of what is good and what is evil. But I have understood that the good is beautiful and the bad is shameful, and that the wrongdoer himself shares my nature — not the same blood, but the same mind and the same portion of the divine. So none of them can harm me, for no one can fasten what is shameful upon me; nor can I be angry with my kinsman or hate him. We were born to work together, like feet, hands, and eyes. To work against one another is contrary to nature.