the arc of the moral universe-by MLK, Jr., on the 50th anniversary of his assassination-a central theme of “killing justice”

When our days become dreary with low-hovering clouds of despair, and when our nights become darker than a thousand midnights, let us remember that there is a creative force in this universe, working to pull down the gigantic mountains of evil, a power that is able to make a way out of no way and transform dark yesterdays into bright tomorrows. Let us realize the arc of the moral universe is long but it bends toward justice. 

- Martin Luther King, Jr.