All historians generalize from particulars. And often, if you look at a historian's footnotes, the number of examples of specific cases is very, very small.

So when you do your family tree and Margaret Cho does hers, and... Wanda Sykes and John Legend... we're adding to the database that scholars can then draw from to generalize about the complexity of the American experience. And that's the contribution that family trees make to broader scholarship.

You notice patterns. White guests often are mortified - that word again - when they learn their ancestors owned slaves. But I've never had a black guest who was upset to learn about white ancestry that probably involved forced sexual relations.

People are afraid, and when people are afraid, when their pie is shrinking, they look for somebody to hate. They look for somebody to blame. And a real leader speaks to anxiety and to fear and allays those fears, assuages anxiety.

Suffering does not necessarily ennoble you.

In America one drop of black ancestry makes you black.