"It's really fascinating how we're all alike and how we're also very different, what works and what doesn't," Oprah says.
Author Elizabeth Gilbert opened up about her first, failed attempt at marriage in her best-selling memoir Eat, Pray, Love. Now, she explores the history of the institution and reveals why she decided to marry again in her latest book, Committed .
Read the first chapter of Committed .
"We have this line that we repeat in this country that the history of marriage is this sacred, ancient, inevitable union between one man and one woman, which is very sweet and it's very lovely," she says. "It just doesn't happen to be true."
Elizabeth says that for centuries marriage was often the union between one man and several women. "In the ancient world, it was a way of gathering kinship and expanding your circle of family. In the medieval world, it was an economic bond," she says. "The only thing that's consistent about the history of marriage is change."