Darkness cannot drive out darkness; only light can do that. Hate cannot drive out hate; only love can do that. Hate multiplies hate, violence multiplies violence, and toughness multiplies toughness in a descending spiral of destruction… The chain reaction of evil — hate begetting hate, wars producing more wars — must be broken, or we shall be plunged into the dark abyss of annihilation.
— Dr. Martin Luther King, Jr. in 1963