SLAVES OF NEW YORK: According to the Times, many visitors to the New York Historical Society's "Slavery in New York" exhibition have been shocked and angered to learn that the "peculiar institution" was once quite common in their city -- apparently, about 40 percent of New York City households contained slaves at one point -- and that it wasn't actually outlawed there until 1827.

"It's terrible to know that the city that I love was part of the slave trade," said a middle-aged white woman from New Jersey. "I'm shocked to hear about it."

An African-American man in the booth with his young daughter said: "It's just a constant reminder that here in New York, like in other places in the United States, we were nothing more than cattle in the eyes of the owners and were treated that way. It's just amazing that people were able to survive and thrive after that."

An elderly white woman who said she had two college degrees said, "I never knew until I walked in here about slavery in New York." Now, she said, "It just breaks my heart."

Yep. As we Southerners know better than most, these sorts of history lessons can be painful indeed. But, as the exhibit's chief historian, Dr. James Oliver Horton, argues, they are also necessary.

"Back in the 90's, when Bill Clinton asked for a national conversation about race, most people didn't have the context in which to have the conversation. This exhibition will help Americans have such a historical context. It will help people start with a common experience."

Pretty to think so, anyway.