What is the greatest sentence ever written? According to author Walter Isaacson, it's a single sentence in the Declaration of Independence:“We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness.”Ahead of America's 250th anniversary, Judy Woodruff spoke with Isaacson about the enduring power of those words and his new book, "The Greatest Senten