"Darkness cannot drive out darkness; only light can do that. Hate cannot drive out hate; only love can do that."

"Human salvation lies in the hands of the creatively maladjusted."

"The arc of the moral universe is long, but it bends toward justice."

"I just want to do God's will. And he's allowed me to go to the mountain. And I've looked over, and I've seen the promised land! I may not get there with you, but I want you to know tonight that we as a people will get to the promised land."

View all photos of the Dr. Martin Luther King Jr. National Memorial in Washington, D.C. on Flickr.