On some positions, cowardice asks the question, is it expedient? And then expedience comes along and asks the question, is it politic? Vanity asks the question, is it popular? Conscience asks the question, is it right?From King's last sermon, "Remaining Awake Through a Great Revolution," Washington National Cathedral, Washington, D.C., March 31, 1968.
Full text, via The Martin Luther King, Jr. Papers Project