Today, you must have heard, is the 40th anniversary of civil rights leader Dr. Martin Luther King, Jr.'s assassination. He was shot to death while standing on the balcony of a Memphis hotel at 6:01 p.m. on April 4, 1968. The night before, he had given his last speech—the prophetic "I've been to the Mountaintop" sermon—in which he told the crowd, "Like anybody, I would like to live a long life. Longevity has its place. But I'm not concerned about that now." King was tired, and had to be specially cajoled to go to the church that night; he ended up delivering his own eulogy. Considering the circumstances, it was his most moving speech of all. Were he alive today, King would be nearing his 80th birthday. A full clip of the speech is below. Have we reached the promised land yet?