freethinking lyricist Yip Harburg, who wrote “Over the Rainbow,” and many other songs. Listen to Yip himself singing “If I Only Had a Brain,” “Over the Rainbow,” “Brother, Can You Spare a Dime?” and “Last Night When We Were Young.” Then we interview Yip’s son, Ernie Harburg, also an atheist, a scientist who is director of the Yip Harburg Foundation, about his father’s artistic life and social activism.