One night in 2002, a friend gave Jorge Drexler the chorus to a song and challenged him to write the rest of it using a complex, poetic form known as the "Décima." In this fascinating talk, Drexler examines the blended nature of identity, weaving together the history of the Décima with his own quest to write one. He closes the talk with a performance of the resulting song, "La Milonga del Moro Judío." (In Spanish with English subtitles)

Carolyn Jones spent five years interviewing, photographing and filming nurses across America, traveling to places dealing with some of the nation's biggest public health issues. She shares personal stories of unwavering dedication in this celebration the everyday heroes working at the front lines of health care.

When stress got to be too much for entrepreneur Sangu Delle, he had to confront his own deep prejudice: that men shouldn't take care of their mental health. In a personal talk, Delle shares how he learned to handle anxiety in a society that's uncomfortable with emotions. As he says: "Being honest about how we feel doesn't make us weak -- it makes us human."

"There are facts, there are opinions, and there are lies," says historian Deborah Lipstadt, telling the remarkable story of her research into Holocaust deniers -- and their deliberate distortion of history. Lipstadt encourages us all to go on the offensive against those who assault the truth and facts. "Truth is not relative," she says.