What drives the decision to live divided no more, with the risks it entails? How do people find the courage to bring inner conviction into harmony with outer act, knowing that when they do, the force of the institution may come down on their heads, risking the loss of image or status or security or money or power? The difference between the person who goes to the back of the bus and one who decides to sit up front is probably lost in the mystery of the human heart. But in Rosa Parks and others like her, I see a clue to an answer: when you realize that you can no longer collaborate in something that violates your own integrity, your understanding of punishment is suddenly transformed.
Parker Palmer, The Courage to Teach